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- From: iglesias@draco.acs.uci.edu (Mike Iglesias)
- Subject: Rec.Bicycles Frequently Asked Questions Posting Part 3/4
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- Date: 30 Nov 92 06:22:23 GMT
- Followup-To: rec.bicycles.misc
-
- Archive-name: bicycles-faq/part3
-
- [Note: The complete FAQ is available via anonymous ftp from
- draco.acs.uci.edu (128.200.34.12), in pub/rec.bicycles.]
-
- ---------------------------------------------------------------------------
-
- Nancy's Cold/Wet Cycling Tips (Nancy Piltch piltch@ariel.lerc.nasa.gov)
-
- Here are some clothing suggestions, mix and match as you wish:
-
- Rain gear : I forked out the dollars for gore-tex when I did a week tour
- ... and I'm real glad I did. The stuff works reasonably as claimed,
- waterproof, and relatively breathable. (When the humidity is high, no
- fabric will work completely at letting sweat evaporate.) Unfortunately,
- typical prices are high. There are cheaper rainsuits, which I haven't tried.
- For short rides, or when the temperature is over about 50F, I don't
- usually wear the rain pants, as wet legs don't particularly bother me.
-
- Waterproof shoe covers. When the weather gets icky, I give up on
- the cleats (I'm not riding for performance then, anyway) and put
- the old-style pedals back on. This is basically because of the
- shoe covers I have that work better with touring shoes. The ones
- I have are made by Burley, and are available from Bikecentennial,
- though I got them at a local shop. They are just the cover, no
- insulation. I continue to use them in winter since they are windproof,
- and get the insulation I need from warm socks. These aren't neoprene,
- but rather some high-tech waterproof fabric.
-
- Gaiters that hikers and cross-country skiers wear can help keep road
- spray off your legs and feet.
-
- Toe clip covers. I got them from Nashbar; they are insulated and fit
- over the toe clips ... another reason for going back to those pedals.
- They help quite a bit when the temperature goes into the 30's and below;
- they are too warm above that.
-
- For temperatures in the 40's I usually find that a polypropylene shirt,
- lightweight sweater (mine is polypro) and wind shell work well; I use
- the gore-tex jacket, since I have it, but any light weight jacket
- is OK. I have a lightweight pair of nylon-lycra tights, suitable in
- the 50's, and maybe the 40's; a heavier pair of polypro tights, for
- 40's, and a real warm pair of heavy, fleece-lined tights for colder
- weather. (I have been comfortable in them down to about 15-deg, which
- is about the minimum I will ride in.) My tights are several years
- old, and I think there are lots more variations on warm tights out now.
- I use thin polypro glove liners with my cycling gloves when it is a little
- cool; lightweight gloves for a little bit cooler; gore-tex and thinsulate
- gloves for cold weather (with the glove liners in the really cold weather.)
- It is really my fingers that limit my cold weather riding, as anything
- any thicker than that limits my ability to work brake levers.
- (Note: this may change this year as I've just bought a mountain bike;
- the brake levers are much more accessible than on my road bike. It may
- be possible to ride with warm over-mitts over a wool or similar glove.)
-
- When it gets down to the 20's, or if it's windy at warmer (!) temperatures,
- I'll add the gore-tex pants from my rain suit, mostly as wind protection,
- rather than rain protection. Cheaper wind pants are available (either
- at bike shops or at sporting goods stores) that will work just as well
- for that use.
-
- Warm socks. There are lots of choices; I use 1 pair of wool/polypropylene
- hiking socks (fairly thick). Then with the rain covers on my shoes to
- keep out wind, and (if necessary) the toe clip covers, I'm warm enough.
- There are also thin sock liners, like my glove liners, but I haven't
- needed them; there are also neoprene socks, which I've never tried,
- and neoprene shoe covers, which I've also never tried, and wool socks,
- and ski socks ...
-
- I have a polypropylene balaclava which fits comfortably under my helmet;
- good to most of the temperatures I'm willing to ride in; a little too
- warm for temperatures above freezing, unless it's also windy. I also have
- an ear-warmer band, good for 40's and useful with the balaclava for
- miserable weather. I also have a neoprene face mask; dorky looking, but
- it works. It is definitely too hot until the temperature (or wind) gets
- severe. I sometimes add ski goggles for the worst conditions, but they
- limit peripheral vision, so I only use them if I'm desperate.
-
- For temperatures in the 30's, and maybe 20's, I wear a polarfleece
- pullover thing under the outer shell. Combining that with or without
- polypro (lightweight) sweater or serious duty wool sweater gives a
- lot of options. Sometimes I add a down vest -- I prefer it *outside*
- my shell (contrary to usual wisdom) because I usually find it too
- warm once I start moving and want to unzip it, leaving the wind
- shell closed for wind protection. I only use the down vest when it's
- below about 15 F.
-
- ---------------------------------------------------------------------------
-
- Studded Tires (Nancy Piltch piltch@ariel.lerc.nasa.gov)
-
- [A summary on studded tires compiled by Nancy. A complete copy of
- the responses she received, including some that give directions for
- making your own studded tires, is in the archive.]
-
- Studded tires do help, especially on packed snow and ice. On fresh snow
- and on water mixed with snow (i.e. slush) they're not significantly different
- from unstudded knobbies.
-
- On dry pavement they are noisy and heavy, but can be used; watch out for
- cornering, which is degraded compared to unstudded tires.
-
- Several people recommend a Mr. Tuffy or equivalent with them; one
- respondent says he gets more flats with a liner than without.
-
- In the U.S. the IRC Blizzard tires are commercially available. They
- can also be made.
-
- ---------------------------------------------------------------------------
-
- Milk Jug Mud Flaps (Chuck Tryon bilbo@bisco.kodak.com)
-
- Actually, I have used plastic like this (or in my case, some
- red plastic from a cheap note book cover -- it's heavier) to extend the
- bottom (rear) end of the front fender. The Zephals are good, but they
- don't stop the splash from where the tire hits the road from getting on my
- feet. What I did was cut a small triangle about 3in (~7cm) wide by 6in
- (~15cm) long, cut a hole in the top of it and the bottom end of the fender,
- and use a pop-rivet (with washers to prevent tear out) to attach it. On a
- road bike, it should be end up being within a few inches of the road. ATB's
- will need more clearance, so this won't work well off road.
-
- | |
- | |
- /| o |\ <----- rivet with washer on inside
- | \___/ |
- / \ <---- flap fits inside of the fender, and follows the
- | | curve, which gives it some stiffness.
- | |
- | |
- \_________/
- | |
- | | <----- bottom of tire
- \_/
-
- ===========================================================================
-
- Touring
-
- Touring supplies (Scott "gaspo" Gasparian gaspar@inf.ethz.ch)
-
- Recently, I asked the group: what do you bring with you on medium
- trips? (medium being more than one nite, and less than a week). I
- received some excellent replies, a few great stories, and lots of things
- that I never would have thought of. (at least not until I needed that
- spare spoke that is).
-
- Ok, for all of you who don't know what to bring with you on that
- next medium trip...
-
-
- FOOD:
- Here, just whatever you normally consume. If you plan on
- staying in a hotel/B&B, then obviously 1 day's worth is enough.
- Standard things like power-bars and drink mixes should do the trick.
- Since I'm not going to BFE, I have no idea what to pack for a real
- "camp-out" type tour. This subject is enough for a discussion in
- itself, but I just eat what I want.
-
- CLOTHING:
- Almost everybody suggested something different, rangin from hi-
- tech bodysuits to cutoffs and T-shirts. However, everybody agreed on the
- indispensibleness (tm) of rain gear. Specifically, light waterproof
- pants and jacket are not only good for staying dry, but have a very high
- warmth/weight ratio.
- A spare change of skivies, and a pair of dry socks were also
- highly recomended. A pair of jeans or a "smushable outfit" can come in
- handy, but I usually smell so bad after a day of riding that anybody who is
- talking to me doesn't care what I wear. If it might be non-warm, a
- watch-cap or other non-helmet type hat can help.
-
- FIRST-AID:
- Outside of the standard band-aids/antiseptic-goop bit, sunscreen
- and bug-away topped the lists. Asprin or Ibuprofen and rolaids were
- mentioned, but I guess thats a personal thing, just like...
-
- TOILETRIES:
- I stick with: soap, toothbrush/paste, deodorant. That covers
- all I need, but everybody has different needs, and I'm not even gonna
- touch the "personal hygeine" stuff. A razor is handy too, it can help
- keep that road-rash dressing from ripping all your remaining hair out.
-
- MISC:
- I'll put the tent/pit stuff into this category. Robyn Stewart
- gave an excellent testamony to the uses of rope and tarps. A piece of
- rope stretched between two trees can keep the food above the
- critter-level, and can also provide a rudimentary tent with the aid of
- an old shower-curtain. Again, there is a whole area of discussion here
- on the pits and mattresses, but if it keeps you warm and dry, it works.
-
-
- TOOLS:
- Basically, this could be split into two different classes, with
- things like tire-kit being in the "fix it yourself" category, and other
- stuff like a chain remover tool is in the "how far will I be from
- civilization" range. This was what I really wanted to know about when I
- posted my request, so a little more info than the first groups.
-
- Most of this depends upon how much work _YOU_ do to your velo. If
- replacing spokes is trivial to you, then you already know what tools to
- bring. Also, wrenches and screwdrivers are very velo dependent: handy
- sizes for a MTB might be useless for a nice racer, and vice-versa. Tools
- that tune more than repair are also an individual call. I always carry
- a hex-wrench that fits my brake-shoe adjustment bolt, but never the larger
- one that actually removes the entire caliper.
-
- pump
- pressure gauge
- flat kit
- wrenches (sizes and type for your velo)
- hex(allen)-wrenches (sizes and type for your velo)
- chain tool
- chain links
- tire levers (plastic)
- spoke wrench
- safety wire
- duct tape
- zip ties
-
- SPARES:
- Again, these fall into "distance from civilization" categories.
- For example, that nut that connects your front mudguard to the forks
- is essential, but could be fixed with the safety wire until you find a
- velo-shop/store that might have a replacement. Then again, one little
- nut is easy on space/weight, and it may be hard to get a replacement if
- your velos measurements are non-standard. If you have a hard-time
- finding a replacement for that random part at your local store, bring
- one with you.
-
- inner tubes
- tire-boots
- brake shoes
- light bulbs
- spokes (labeled if different, tied to the frame)
- nuts and bolts for rack/fenders/etc.
- tire (if you're _really_ out there)
- toe-clip strap
- shoe-laces
- cable (especially if yours are longer than normal).
- cable housing (for the shimano special shifter ones)
-
- NIFTY IDEAS:
- Here are some of the better inside tips that I found both
- humorous and usefull....
-
- mjohnsto@shearson.com (Mike Johnston)
- A sock (to keep tools inside and for keeping grease off my hands
- during rear wheel flats)
-
- s_kbca@dante.lbl.gov (Steve Kromer)
- The most important article to take along on a long ride
- seems to be faith.
-
- chris@wg.estec.esa.nl (chris rouch)
- 15cm of old tyre
-
- Robyn Stewart <slais02@unixg.ubc.ca>
- Enough money to get Greyhound home if something goes terribly wrong.
-
- sarahm@Cadence.COM
- bungie cords - you never know when you might want to get that
- set of six beer mugs as a souvenir and transport it on the
- back of your bike.
-
- cathyf@is.rice.edu (Catherine Anne Foulston)
- ZAP Sport Towel. I think it is really useful because you can
- get it wet and it still dries you.
-
- ===========================================================================
-
- Cycling Myths
-
- Following are various myths about cycling and why they are/aren't true.
-
-
- Myth: Wearing a helmet makes your head hotter than if you didn't wear one.
-
- Actual measurements under hard riding conditions with ANSI standard
- helmets show no consistent temperature difference from helmetless
- riders. Part of the reason is that helmets provide insulated
- protection from the sun as well as some airflow around the head.
- (Les Earnest Les@cs.Stanford.edu)
-
-
- Myth: You need to let the air out of your tires before shipping your bike
- on an airplane - if you don't, the tires will explode.
-
- Assume your tire at sea level, pumped to 100 psi. Air pressure at sea
- level is (about) 15psi. Therefore, the highest pressure which can be
- reached in the tire is 100+15=115psi. Ergo: There is no need to
- deflate bicycle tires prior to flight to avoid explosions.
- (Giles Morris gilesm@bird.uucp)
- Addendum: The cargo hold is pressurized to the same pressure as the
- passenger compartment.
- (Tom ? tom@math.ufl.edu)
-
-
- Myth: You can break a bike lock with liquid nitrogen or other gases
-
- Freon cannot cool the lock sufficiently to do any good. Steel
- conducts heat into the cooling zone faster than it can be removed by a
- freeze bomb at the temperatures of interest. Liquid nitrogen or other
- gasses are so cumbersome to handle that a lock on a bike cannot be
- immersed as it must be to be effective. The most common and
- inconspicuous way to break these locks is by using a 4 inch long 1
- inch diameter commercial hydraulic jack attached to a hose and pump
- unit.
- (Jobst Brandt jobst_brandt%01@hp1900.desk.hp.com)
-
- [More myths welcome!]
-
- ===========================================================================
-
- Buying a Bike
-
- One thing to decide before buying a bike is what type to buy. Here's a
- brief list:
-
- Road bike Once known as a "ten-speed", most are now 12 or 14 (or even
- 16) speed. There are several sub-types: racing, sport,
- and touring, the difference mostly in frame geometry.
-
- ATB All-terrain bike, also known as mountain bike. Great for
- riding in the dirt, these bikes usually have fat, knobby
- tires for traction in dirt and gravel.
-
- Hybrid A bike that borrows from road bikes and ATBs. For example,
- they have the light frame and 700c wheels of road bikes and
- fat knobby tires, triple cranks, wide-range derailleurs,
- flat handlebars and cantilever brakes from mountain bikes.
-
-
- Bike buying hints
-
- When you're ready to buy a bike, you should first decide what you want
- to use the bike for. Do you want to race? Do you want to pedal along
- leisurely? Do you want to ride in the dirt?
-
- Next, you should decide on a price range. Plan to spend at least
- $350 for a decent quality bike.
-
- Now find a good bike shop. Ask friends who bike. Ask us here on the
- net. Chances are, someone here lives in your area and can recommend
- a shop.
-
- Now that you are ready to look for a bike, visit the shop(s) you have
- selected. Test ride several bikes in your price range. How does it
- feel? Does it fit you? How does it shift? Does it have the features
- you are looking for? How do the shop personnel treat you? Remember
- that the shop gets the bike disassembled and has to spend a couple of
- hours putting it together and adjusting things, so look for sloppy
- work (If you see some, you may want to try another shop). You might
- want to try a bike above your price range to see what the differences
- are (ask the salesperson).
-
- Ask lots of questions - pick the salesperson's brain. If you don't
- ask questions, they may recommend a bike that's not quite right
- for you. Ask about places to ride, clubs, how to take care of your
- bike, warranties, etc. Good shops will have knowledgable people
- who can answer your questions. Some shops have free or low-cost
- classes on bike maintenance; go and learn about how to fix a flat,
- adjust the brakes and derailleurs, overhaul your bike, etc.
- Ask your questions here - there are lots of people here just waiting
- for an excuse to post!
-
- Make sure that the bike fits you. If you don't, you may find that
- you'll be sore in places you never knew could be so sore. For road
- bikes, you should be able to straddle the top tube with your feet flat
- on the ground and still have about 1 inch of clearance. For mountain
- bikes, give yourself at least 2-3 inches of clearance. You may need
- a longer or shorter stem or cranks depending on your build - most
- bikes are setup for "average" bodies. The bike shop can help you
- with adjustments to the handlebars and seat.
-
- Now that you've decided on a bike, you need some accessories. You
- should consider buying
-
- a helmet
- a frame pump
- a tube repair kit
- tire levers (plastic)
- a pressure gauge
- a seat pack (for repair kit, wallet, keys, etc)
- gloves
- a water bottle and cage
- a lock
-
- The shop can help you select these items and install them on your bike.
-
-
- ===========================================================================
-
- Chains
-
-
- Lubricating Chains
-
- Lubricating chains is a somewhat religious issue. Some advocate oil,
- some Teflon-base lubricants, some paraffin wax. The net majority favors
- a lubricant that does not leave an oily coating on the chain that can
- attract dirt, which will hasten chain/chainring/freewheel sprocket wear.
-
- If you want to use paraffin wax, make sure you melt the wax in a double
- boiler! Failure to do so can lead to a fire. You can use a coffee
- can in a pan of boiling water if you don't want to mess up good cookware.
- After the wax has melted, put the chain in the wax and simmer for 10
- minutes or so. Remove the chain, hang it up, and wipe the excess wax
- off. Let it cool and reinstall on your bike.
-
- When using a liquid lubricant, you want to get the lube onto the pins
- inside the rollers on the chains, not on the outside where it does little
- good. Oilers with the narrow tubes are good for this because you can put
- the lube where you want it. Work the oil into the chain after applying
- it, wipe the chain off, and reinstall on your bike.
-
- ---------------------------------------------------------------------------
-
- Wear and Gear Slippage (Jobst Brandt jobst_brandt@hplabs.hp.com)
-
- There seems to be a lot of speculation on what makes chains wear
- and how to lubricate a chain. There are a number of ways to take
- care of a chain. Some traditional methods are the most damaging
- to chain life and others work to prolong life.
-
- As was mentioned on the net, chains don't stretch in the sense
- that the metal elongates, but the parts wear. Wear in the pins
- and sleeves change the length of the chain as the pins fit more
- loosely. The wear arises primarily from road grit that enters
- the chain when it is oiled. Grit on the outside of a chain looks
- bad but it has no effect on the function because it can't get
- inside to do damage. Only when a dirty chain is oiled does this
- grit get to the place where it can cause damage. Note that
- commercial abrasive grinding paste is made of oil and silicon
- dioxide (sand) and silicon carbide (sand). You couldn't do a
- better job if you tried to destroy a chain than to oil a road
- dirt (previously oiled) encrusted chain.
-
- Primitive rule #1: Never oil a chain on the bike.
-
- This means you should clean the grit off the chain before oiling
- it. Because this is essentially impossible without submerging
- the chain in a solvent bath (kerosene or commercial solvent), you
- must take the chain off the bike. The fine grit can only be
- removed from the interior of the chain in liquid suspension. A
- good example of this can be seen by using a Vetta (on the bike)
- chain cleaner and subsequently cleaning the same chain in a
- solvent bath. The best grit remains until last and there's
- plenty of it.
-
- Removing the solvent from the chain after the rinse is important.
- Compressed air is not readily available in the household nor is a
- centrifuge. You can go outdoors and sling the chain around.
- This works best if the chain is a closed loop. You don't have to
- press the pin completely in for this. The other way is to
- evaporate it. You should probably avoid accelerated drying
- methods because they could be explosive.
-
- The hot gear lube method works but it also acts as efficient fly
- paper, collecting plenty of grime between cogs. Motor oil is good
- but motorcycle chain lubes are better because they have volatile
- solvents that allow good penetration for relatively viscous
- lubricant. Paraffin is useless because it is not mobile and
- cannot replenish the bearing surface once it has been displaced.
-
- Sedisport
-
- The Sedisport chain, although the strongest and one of the
- lightest chains, achieves its light weight at the expense of
- durability. This chain has omitted the sleeve that on most
- roller chains supports the roller on its outside and furnishes
- the bearing for the pin on the inside. Normally the inside of
- the sleeve is well protected against lubricant depletion because
- both ends are covered by closely fitting side plates. In the
- Sedisport there is no sleeve and the formed side plates support
- the roller and pin with a substantial central gap. In the wet,
- lubricant is quickly washed out of pin and roller and the inferior
- bearing for the pin and roller often gall and bind. In good
- weather this is not a problem. Because this chain has feet of
- clay in the wet, Sedis re-introduced their earlier 5 element
- conventional chain, calling it a "chain for all seasons".
-
- The lightweight Regina chain goes one step farther and omits the
- pin, leaving the side plates to hinge directly on the sleeve.
- This gives them a knife edge bearing area that galls at the
- slightest lube depletion.
-
- Chain Life
-
- This is almost entirely a cleanliness and lubrication question
- rather than a load problem. The effect of load variations is
- insignificant when compared to the lube and grit effects for
- bicycles. The primary chains on motorcycles are operated under
- clean conditions and last years while the exposed rear chains
- must be replaced often.
-
- The only way to test whether a chain is worn is by measurement.
- The chain has a half inch pitch and, when new, has a pin at
- exactly every half inch. As the pins and sleeves wear this
- spacing increases and becomes damaging to sprockets. When the
- chain pitch grows over one half percent it is time for a new
- chain. At one percent chainring damage progresses rapidly. By
- holding a ruler along the chain on your bile, align an inch mark
- with a pin and see how far off the mark the pin is at twelve
- inches. An eighth of an inch (0.125) is the ten percent limit
- while more than a sixteenth is a prudent time to get a new chain.
-
- Skipping Chain
-
- When you put on a new chain, its pitch is exactly one half inch.
- A sprockets worn by a longer pitch chain pockets in its teeth.
- These pockets are formed by the rollers of a worn chain as they
- exit the sprocket under load. Rollers of a new chain with
- correct pitch exit under no load because the load is transferred
- to the next roller before disengagement. However, with hooked
- sprockets the new chain cannot engage under load because the
- pitch is too small to get over the hook and into the pocket.
- These differences are only a few thousandths of an inch but that
- is enough to prevent engagement when the previous roller is in
- its pocket.
-
- As a chain wears it concentrates more of its load on the last
- tooth of a sprocket before disengagement because its pitch no
- longer matches the pitch of the sprocket. This effect sometimes
- breaks off sprocket teeth. The load concentration on the
- sprocket also accelerates wear and is another reason to replace a
- chain at 1/16th inch wear.
-
- ---------------------------------------------------------------------------
-
- Adjusting Chain Length (Bob Fishell spike@cbnewsd.att.com)
-
- For all Shimano SIS and Hyperglide systems, the chain is sized by shifting to
- the smallest rear cog and the largest front sprocket, then sizing the
- chain so that the derailleur pulleys are on a vertical line, or as close
- as you can get to it. Note that this will result in the same chain length
- for any freewheel within the capacity of the derailleur, so it usually is
- not necessary to re-size the chain for a different cogset with these systems.
-
- The other rule I've used (friction systems) involves shifting to the largest
- chainring and the largest rear cog, then sizing the chain so that the pulleys
- are at a 45 degree angle to the ground.
-
- The rules probably vary from derailleur to derailleur. In general,
- you may use the capacity of the rear derailleur cage as a guideline. You
- want the chain short enough so the cage can take up the slack in the
- smallest combination of chainwheel and rear cog you will use. The chain
- must also be long enough so that the cage still has some travel in the
- largest combination you will use.
-
- For example, if you have a 42x52 crank and a 13x21 freewheel, the smallest
- combination you would use would be a 42/14 (assuming you don't use the
- diagonal). If the cage can take up the slack in this combo, it's short enough.
- If the cage has spring left when you are in the 52/19 combo (again, you are
- not using the diagonal), it's long enough.
-
- ---------------------------------------------------------------------------
-
- Hyperglide chains
-
- When you need to replace a Shimano Hyperglide chain, use a Sedis ATB
- chain. It's compatible with the Hyperglide system and doesn't need
- a special pin to put the chain back together when you take it apart.
-
- ===========================================================================
-
- Cranks and Bottom Brackets
-
- Bottom Bracket Info (Jobst Brandt jobst_brandt@hplabs.hp.com)
-
- The four kinds of BB threads in common use today are Italian, British,
- French, and Swiss, possibly in that order of occurrence.
-
- Diameter Pitch Right Left Cup
- -------- ----- ----- -----
- Italian 36mm x 24F tpi right right tpi (threads per inch)
- British 1.370" x 24F tpi left right
- French 35mm x 1mm right right
- Swiss 35mm x 1mm left right
-
- Unless there is something wrong with the right hand cup it should not be
- removed but should be wiped clean and greased from the left side. The
- thread type is usually marked on the face of both left and right cups.
- Swiss threads are rare but if you have one it is good to know before
- attempting removal.
-
- ---------------------------------------------------------------------------
-
- Crank noises (Phil Etheridge phil@massey.ac.nz)
-
- I've had the creaky crank problem on every bike I've owned which has
- had cotterless cranks. Until now, I've never known a good solution to
- the problem.
-
- One suggestion I had was to replace the crank, but that wasn't
- something I was prepared to do on 1 month old bike under warranty.
- The shop mechanic spent half an hour with me and my bike sorting it
- out. Tightening the crank bolts and pedal spindle (i.e. onto the
- crank) didn't help (as Jobst will tell you).
-
- Removing each crank, smearing the spindle with grease and replacing
- the crank eliminated most of the noise. Removing each pedal, smearing
- grease on the thread and replacing it got rid of the rest of the
- noise.
-
- Greasing the pedal threads is a new one on me, but it makes a lot of
- sense, since they are steel and the crank aluminum. I thought it was
- worth relating this story, as creaky cranks seems to be quite a common
- problem.
-
- ---------------------------------------------------------------------------
-
- Cracking/Breaking Crankarms (Jobst Brandt jobst_brandt@hplabs.hp.com)
-
- [Ed note: Yes, another disputed issue is contained here - whether to
- lube the crank tapers before installing the crankarms. This has
- popped up from time to time on rec.bicycles, and has never been
- resolved one way or the other. The text here is Jobst's viewpoint.]
-
- Cranks break because they are aluminum and because they have high
- stress at various points. The worst of these points are at the
- pedal eye and where the spider fingers join the right crank. The
- pedal eye is a bad place because the joint is incorrectly designed,
- but since it is a standard, it may not be changed since it seems to
- work. This joint always moves and causes fretting corrosion and
- cracks. These cracks propagate into the crank and cause failure.
- A better joint here would be a 45 degree taper instead of a flat
- shoulder at the end of the pedal thread.
-
- The thin web between the spider and crank, another common crack
- origin on cranks like the Campagnolo Record, was nicely redesigned
- in the C-Record crank, but to make up for that the C-Record is
- otherwise weaker than the Record version. My experience is that
- they break in about 1500 miles because the pedal eye has a smaller
- cross section than the Record model, but maybe the alloy is poorer
- too. I have subsequently used Dura Ace cranks for more than two
- years with no failure yet. I don't believe in eternal life here
- either.
-
- Aluminum has no safe fatigue limit but just gets progressively safer
- as stress is reduced. In contrast, steel has a threshold below
- which failures cease. Therein lies some of the problem.
-
- As for cranks loosening, one can view the junction between spindle
- and crank in an exaggerated elastic model where the spindle is made
- of plastic and the crank of Rubbermaid household rubber. The crank,
- once properly installed and the retaining bolt in place, squirms on
- the square taper when under torque. During these deformations the
- crank can move only in one direction because the bolt prevents it
- from coming off. The crank always slides farther up the taper.
- Proof that the crank squirms is given by the fretting rouge always
- found on the spindle, whether lubricated or not, when a crank is
- pulled off after substantial use.
-
- As was mentioned by various observers, the left crank bolt is
- usually looser, after use, than the right one and this could be
- anticipated because the two cranks differ in their loading. This
- does not mean the left crank is looser. Actually it is tighter,
- only the bolt is looser. The left crank is more heavily loaded
- because it experiences offset twist from the pedal at the same time
- it transmits torque to the spindle. The right crank, being
- connected to the chain, experiences either spindle torque from the
- left pedal or twist from the right pedal but not torque and twist at
- the same time.
-
- In this squirming mode, cranks wander away from the retaining bolt
- and leave it loose after the first hard workout (for riders of more
- than 150 lbs). The bolts should NOT be re-tightened because they
- were correctly tight when installed. Cranks have been split in half
- from repeated follow-up tightening, especially left cranks. The
- spindle should be lubricated before installing cranks. A wipe of a
- mechanic's finger is adequate since this is to prevent galling in
- the interface. To prevent losing a loose crank bolt, the "dust"
- cover that is in fact the lock cap should be installed.
-
- Those who have had a crank spindle break, can attest to the greater
- stress on the left side because this is the end that always breaks
- from fatigue. A fatigue crack generally has a crystalline
- appearance and usually takes enough time to develop that the face of
- the fracture oxidizes so that only the final break is clean when
- inspected. Because a notch acts to concentrate stress, the
- advancing crack amplifies this effect and accelerates the advance
- once the crack has initiated.
-
- I have heard of instructions to not lubricate spindles before
- installing cranks but I have never been able to find it in any
- manufacturer's printed material. Although I have broken many
- Campagnolo cranks, none has ever failed at the spindle. I am
- certain that the standard machine practice of lubricating a taper
- fit has no ill effects. I have also never had a crank come loose
- nor have I re-tightened one once installed.
-
- ---------------------------------------------------------------------------
-
- Biopace chainrings
-
- Biopace chainrings have fallen into disfavor in recent years. They
- are hard to "pedal in circles". The early Biopace chainrings were
- designed for cadences of around 50-70 rpm, while most recommend a
- cadence of 80-100 rpm. Newer Biopace chainrings are less elliptical,
- but the general consensus is to (if you are buying a new bike) get the
- dealer to change the chainrings to round ones.
-
- ===========================================================================
-
- Tires and tubes
-
- Snakebite flats
-
- Snakebite flats are usually caused by the tire and tube being pinched
- between the road and the rim, causing two small holes in the tube that
- look like a snakebite. The usual causes are underinflation, too
- narrow a tire for your weight, or hitting something (rock, pothole)
- while having your full weight on the tire.
-
- The obvious solutions are to make sure your tires are inflated properly,
- use a larger size tire if you weigh a lot, and either avoid rocks and
- potholes or stand up with your knees and elbows flexed (to act like shock
- absorbers) when you go over them.
-
- ---------------------------------------------------------------------------
-
- Blown Tubes (Tom Reingold tr@samadams.princeton.edu)
-
- Charles E Newman writes:
-
- $ Something really weird happened at 12:11 AM. My bike blew a
- $ tire while just sitting parked in my room. I was awakened by a noise
- $ that scared the livin ^&$% out of me. I ran in and found that all the
- $ air was rushing out of my tire. How could something like happen in the
- $ middle of the night when the bike isn't even being ridden? I have
- $ heard of it happening when the bike is being ridden but not when it is
- $ parked.
-
- This happened because a bit of your inner tube was pinched between your
- tire bead and your rim. Sometimes it takes a while for the inner tube
- to creap out from under the tire. Once it does that, it has nothing to
- keep the air pressure in, so it blows out. Yes, it's scary. I've had
- it happen in the room where I was sleeping.
-
- To prevent this, inflate the tire to about 20 psi and move the tire
- left and right, making sure no part of the inner tube is pinched.
-
- ---------------------------------------------------------------------------
-
- Mounting Tires (Douglas Gurr dgurr@daimi.aau.dk)
-
- A request comes in for tyre mounting tricks. I suspect that this ought to be
- part of the FAQ list. However in lieu of this, I offer the way it was taught
- to me. Apologies to those for whom this is old hat, and also for the paucity
- of my verbal explanations. Pictures would help but, as always, the best bet
- is to find someone to show you.
-
- First of all, the easy bit:
-
- 1) Remove the outer tyre bead from the rim. Leave the inner bead.
- Handy hint. If after placing the first tyre lever you
- are unable to fit another in because the tension in the bead is too great
- then relax the first, slip the second in and use both together.
- 2) Pull out the tube finishing at the valve.
- 3) Inspect the tube, find the puncture and repair it.
-
- Now an important bit:
-
- 4) Check tyre for thorns, bits of glass etc - especially at the point where
- the hole in the tube was found.
-
- and now a clever bit:
-
- 5) Inflate the tube a _minimal_ amount, i.e. just sufficient for it to
- hold its shape. Too much inflation and it won't fit inside the tyre.
- Too little (including none at all) and you are likely to pinch it.
-
- More important bits:
-
- 6) Fit the tube back inside the tyre. Many people like to cover the tube in
- copious quantities of talcum powder first. This helps to lubricate
- the tyre/tube interface as is of particular importance in high pressure
- tyres.
- 7) Seat the tyre and tube over the centre of the rim.
- 8) Begin replacing the outer bead by hand. Start about 90 degrees away from
- the valve and work towards it. After you have safely passed the valve,
- shove it into the tyre (away from the rim) to ensure that you have
- not trapped the tube around the valve beneath the tyre wall.
-
- Finally the _really_ clever bit:
-
- 9) When you reach the point at which you can no longer proceed by hand,
- slightly _deflate_ the tube and try again. Repeat this process until
- either the tyre is completely on (in which case congratulations)
- or the tube is completely deflated. In the latter case, you will have
- to resort to using tyre levers and your mileage may vary. Take care.
-
- and the last important check:
-
- 10) Go round the entire wheel, pinching the tyre in with your fingers
- to check that there is no tube trapped beneath the rim. If you
- have trapped the tube, deduct ten marks and go back to step one.
- Otherwise ....
-
- 11) Replace wheel and reinflate.
-
- ---------------------------------------------------------------------------
-
- More Flats on Rear Tires (Jobst Brandt jobst_brandt%01@hp1900.desk.hp.com)
-
- Most sharp obstacles except tetrahedral glass slivers and puncture
- vine gets stuck more often is that the front tire upsets the sharp
- object just in time for the rear tire to catch it head-on.
-
- This front to rear effect is also true for motor vehicles. Nails lying
- on the road seldom enter front tires. When dropped on the road by a
- moving vehicle, the nail slides down the road aligning itself pointing
- toward traffic because it tends to roll around until it is head first.
- The tire rolls over it and tilts it up so that if the speed is ideal,
- the rear tire catches it upright. I once got a flat from a one inch
- diameter steel washer that the rear tire struck on edge after the front
- tire flipped it up.
-
- When it is wet glass can stick to the tire even in the flat orientation
- and thereby get a second chance when it comes around again. To add to
- this feature, glass cuts far more easily when wet as those who have cut
- rubber tubing in chemistry class may remember. A wet razor blade cuts
- latex rubber tubing in a single slice while a dry blade only makes a
- nick.
-
- ---------------------------------------------------------------------------
-
- Anodized vs. Non-anodized Rims (Jobst Brandt jobst_brandt@hplabs.hp.com)
-
- There are several kinds of dark coatings sold on rims. Each suggests that
- added strength is achieved by this surface treatment while in fact no useful
- effects other than aesthetic results are achieved. The colored rims just
- cost more as do the cosmetically anodized ones. The hard anodized rims do
- not get stronger even though they have a hard crust. The anodized crust is
- brittle and porous and crazes around spoke holes when the sockets are riveted
- into the rim. These cracks grow and ultimately cause break-outs if the
- wheel is subjected to moderate loads over time.
-
- There is substantial data on this and shops like Wheelsmith, that build many
- wheels, can tell you that for instance, no MA-2 rims have cracked while MA-40
- rims fail often. These are otherwise identical rims.
-
- Hard anodizing is also a thermal and electrical insulator. Because heat is
- generated in the brake pads and not the rim, braking energy must cross the
- interface to be dissipated in the rim. Anodizing, although relatively thin,
- impedes this heat transfer and reduces braking efficiency by overheating the
- brake pad surfaces. Fortunately, in wet weather, road grit wears off the
- sidewall anodizing and leaves a messy looking rim with better braking.
-
- Anodizing has nothing to do with heat treatment and does not strengthen rims.
- To make up for that, it costs more.
-
- ---------------------------------------------------------------------------
-
- Clinchers vs. Tubulars (F.J. Brown F.Brown@massey.ac.nz)
-
- D.H.Davis@gdt.bath.ac.uk gave some useful hints on mounting clinchers,
- mostly involving the use of copious quantities of baby powder, and
- trying to convince me that clinchers aren't difficult to mount, so ease of
- mounting isn't a valid reason for preferring tubulars.
-
- wernerj@lafcol.lafayette.edu wrote that although average tubulars ride
- 'nicer' than average clinchers, there are some clinchers around that ride
- just as 'nice'. He also said that ease of change isn't a good reason for
- preferring tubulars as if you flat in a race, you're either going to swap
- a wheel or drop out. He pointed out that tubulars end up costing $20 -
- $80 per flat.
-
- ershc@cunyvm.cuny.edu gave some of the historic reasons that tubulars were
- preferred: higher pressures, lower weight, stronger, lighter rims. Said
- that only a few of these still hold true (rim strength/weight, total weight),
- but he still prefers the 'feel' of tubulars.
-
- leka@uhifa.ifa.hawaii.edu started this thread with his observations on
- clinchers seperated from their rims in the aftermath of a race crash.
-
- stek@alcvax.pfc.mit.edu comments on improperly-glued tubulars posing a threat
- to other racers by rolling off, and noted that this couldn't happen with
- clinchers.
-
- jobst_brandt@hplabs.hp.com agreed with stek, with the additional note that
- it is inadequate inflation that often allows tubulars to roll.
-
- Kevin at Buffalo agreed with stek and jobst about tubulars (improperly or
- freshly glued) sometimes rolling.
-
- ruhtra@turing.toronto.edu says he uses clinchers for cost and convenience.
- Clinchers let him carry around a tiny patch kit and some tyre irons, costing
- 60c, whereas tubulars would require him to carry a whole tyre, and would
- cost more.
-
- CONCLUSIONS: THE CLINCHER VS. TUBULAR WAR
- Tubulars - used to be capable of taking higher pressures, had lower weight
- and mounted onto stronger, lighter rims than clinchers. Clinchers
- have now largely caught up, but many cyclists thinking hasn't.
- Tubular tyre + rim combination still lighter and stronger.
- - are easier to change than clinchers. This matters more to some
- people than others - triathletes, mechanical morons and those
- riding in unsupported races.
- - cost megabucks if you replace them every time you puncture.
- ***However*** (and none of the North Americans mentioned this)
- down here in Kiwiland, we ***always*** repair our punctured
- tubulars (unless the casing is cut to ribbons). The process
- doesn't take much imagination, you just unstitch the case, repair
- the tube in the normal manner using the thinnest patches you can
- buy, stitch it back up again and (the secret to success) put a
- drop of Superglue over the hole in the tread.
- - can roll off if improperly glued or inflated. In this case, you
- probably deserve what you get. Unfortunately, the riders behind
- you don't.
-
- Clinchers - can be difficult to change (for mechanical morons) and are always
- slower to change than tubulars. Most people still carry a spare
- tube and do their repairs when they get home.
- - are cheaper to run: if you puncture a lot clinchers will probably
- still save you money over tubulars, even if you repair your
- tubulars whenever possible. Tubulars are only repairable most
- of the time, you virtually never write off a clincher casing due
- to a puncture.
- - have improved immensely in recent years; top models now inflate
- to high pressures, and are lighter and stronger than they used
- to be. Likewise clincher rims. Some debate over whether
- tubulars are still lighter and tubular rims stronger. Probably
- depends on quality you select. No doubt that high quality
- clinchers/rims stronger, lighter and mor dependable than cheap
- tubular/rim combination.
-
- ---------------------------------------------------------------------------
- Presta Valve Nuts (Jobst Brandt jobst_brandt@hplabs.hp.com)
-
- Two points here:
-
- 1. The jamb nut holds the stem when pumping so that it does not recede
- into the rim when pressing the pump head against the tire. This is
- especially useful when the tire is flat (after installing the tube).
- It also keeps the stem from wiggling around while pumping. I have
- not had difficulty in removing the nut over these many years of
- bicycling. When hands are very cold this is a problem, but then so
- is everything else. Just opening the valve nut on a Presta valve
- can be difficult under such conditions.
-
- 2. Breaking off stems while using a frame pump is a misunderstanding of
- the concept. I find new tubes along the roadside with broken off
- stems. The pump head is to be held in the fist and pumping force is
- supposed to be between the hands, not the hand and the rim. To
- practice this action take the pump in hand with the thumb over the
- outlet and pump vigorously letting no air out. No net force should
- escape since there is no other body involved. This is essentially
- what should take place when pumping a tire.
-
- That the some of the people who do not grasp this concept have
- deficient thinking is proved by their discarding the evidence along
- the road. They also have no concept of blatant littering for which
- there are large fines in this area. They probably think it serves
- the stupid tube right for breaking off. I think otherwise. It is
- unfortunate that bike shops do not instruct new bike owners about the
- use of the frame pump and some tire patch hints like don't try to
- ride a freshly patches tube, carry a spare and always use the spare
- after patching the current tube. I think we covered that extensively
- here earlier. If it isn't in the FAQ it should be.
-
- ---------------------------------------------------------------------------
- Ideal Tire Sizes (Jobst Brandt jobst_brandt@hplabs.hp.com)
-
- > I'm getting a custom frame built and wondered what
- > people thought of using 26 inch road wheels. Smaller
- > wheels ought to be lighter and stronger.
-
- and goes on to list advantages and disadvantages, most of which are less
- that important in deciding what size to use. What in fact brought us
- the wheel size (700 or 27") that we have is better understood by the
- women riders who have a hard time fitting these wheels into their small
- bicycle frames. Wheels would be larger than they are if they would fit
- the average riders bike, but they don't. So the compromise size is what
- we are riding today.
-
- > It seems to me that the most obvious reason for using 27"
- > wheels is tradition, but I'm not sure the advantages make
- > it worth trying to swim upstream. What do you think?
-
- This line of thought is consistent with the "cost be damned" approach
- in bicycling today. The big bucks are spent by people who want the best
- or even better than their peers. The more special the better. Riders
- consistently spend nearly twice the money for wheels and get worse rims
- when they choose anodized ones, whether there is merit to this finish
- is of no interest. They cost more so they must be better. How "custom"
- can you get than to have wheels no one else on the block has (maybe 25"?).
-
- If enough riders ask for 24", 25" and 26" wheels, manufacturers will up
- the price as their product lines multiply and the total sales remain
- constant. Tires and spokes will follow as a whole range of sizes that
- were not previously stocked become part of the inventory. Meanwhile,
- bike frames will come in different configurations to take advantage of
- the special wheel sizes. SIzes whose advantages are imperceptibly small
- but are touted by riders who talk of seconds saved in their last club TT
- or while riding to work.
-
- A larger wheel rides better on average roads and always corners better
- because it brings a longer contact patch to the road. A longer contact
- averages traction over more pavement and avoids slip outs for lack of
- local traction. Visualize crossing a one inch wide glossy paint stripe
- with a 27" wheel and an 18" wheel when banked over in a wet turn.
-
- I see this subject arise now and then and it reminds me of the concept of
- splitting wreck.bike into several newsgroups. The perpetrators bring the
- matter up for many of the wrong reasons.
-
- Ride bike, don't re-invent what has been discarded.
-
- ===========================================================================
-
- Headsets, Forks
-
- Indexed Steering (Jobst Brandt jobst_brandt@hplabs.hp.com)
-
- > In the several years I spent working in a pro shop, I have never seen a
- > case of "index steering" (yes, we called it that) that was _not_ caused
- > by a "brinelled" headset - one with divots in the races. I am 99.999
- > percent certain that that is your problem. What are you going to do if
- > you don't fix it? I suggest that you fix the headset even if you sell
- > the bike, as a damaged headset could be grounds for a lawsuit if the
- > buyer crashes.
-
- I disagree on two points. First, because the use of the term brinelling
- conveys a notion as incorrect as the phrase "my chain stretched from
- climbing steep hills" and second, because there is no possibility of
- injury or damage from an "indexed" head bearing.
-
- Damage to the head bearings seems to be twofold in this case because the
- steering, if properly adjusted, only gets looser from dimpled bearings and
- would not become arrested by the dimples. So the head was adjusted too
- tight or it got tighter inadvertently. However, dimpling is caused by
- lubrication failure and occurs while riding straight ahead. This condition
- is worsened by a tight bearing while a loose bearing would introduce more
- lubricant if it were to rattle.
-
- If you believe it comes from hammering the balls into the races, I suggest
- you try to cause some dimples by hammering with a hammer onto the underside
- of the fork crown of a clunker bike of your choice. Those who pounded in
- cotters on cottered cranks will recall no such dimpling on the BB axle and
- even though this is a far smaller bearing race than a head bearing and the
- blows are more severe and direct, no dimples were made.
-
- Ball bearings make metal-to-metal contact only when subjected to fretting loads
- (microscopic oscillations) while in the same position, as in riding straight
- ahead on a conventional road. If you watch your front axle while rolling
- down the road at 20+ mph you will notice that the fork ends vibrate fore and
- aft. This motion arises not at the blade tips but at the fork crown and
- articulates the head bearing in fretting motions that are not in the normal
- direction of bearing rotation. Any substantial steering motion replenishes
- lubrication from adjoining areas.
-
- Lubrication failure from fretting causes welding between the balls and
- races and these tiny weld spots tear out repeatedly. The result is that at
- the front and rear of the races elliptical milky dimples occur. Were these
- brinelling (embossed through force) they would be shiny and round. Various
- testimonials for the durability of one bearing over another may be based on
- good experience, however, the differences in most of these was not in the
- design of the bearing but rather the type of lubricant used. A ball bearing
- is not suitable for this use. This is in spite of their use in almost all
- bicycles.
-
- To reduce point loads and to protect the rolling elements from fretting
- motion, roller bearing head bearings have been built. In these the rotary
- motion is taken up in needle bearings on conical races and the fork
- articulation is absorbed by an approximation of a spherical cup (the steel
- race) against the aluminum housing. Both of these bearings are ideally
- loaded. The rollers all remain in contact and carry rotary motion while
- the plain spherical bearing remains in full contact carrying low pressure
- fore and aft motion.
-
- I am disappointed that roller bearings until now have not been suitably
- perfected to rid us of the age old bearing failure. Maybe some day soon
- Sun Tour, Campagnolo, Shimano or Stronglight will emerge with an easily
- adjustable and fully compatible bearing. The one I am using is durable but
- not easily adjusted and it has too great a stack height to qualify for a
- recommended replacement.
-
- ===========================================================================
-
- Brakes
-
- Center Pivot vs. Dual Pivot Brakes (Jobst Brandt jobst_brandt@hplabs.hp.com)
-
- Sidepull (one central pivot) brakes operate at a small angle to the
- rim. That means the pad moves in a nearly perpendicular direction to
- the braking surface and the pads can be completely worn down without
- adjusting their position. The unit is light and has a self contained
- quick release and cable adjustment feature.
-
- Its weakness is its thin arms that, in the pursuit of light weight,
- flex in the bending direction. With the current practice to minimize
- tire clearance on road bicycles, sidepull brakes cannot be used off
- road for lack of dirt clearance. Their return spring is anchored in a
- way that relative motion occurs between it and the brake arms. This
- motion demands lubrication and in its absence the brake does not
- center itself. This is a perpetual problem that has not been solved
- and has given rise to many designs, the latest of which is the Shimano
- dual pivot brake. This brake has the disadvantage that it cannot
- track a wobbly wheel because it is forced to be centered.
-
- The cantilever and centerpull brakes are inversions of the same
- design. Both have pivot points that are at 45 degrees to the brake
- surface, but the centerpull offers no advantage over sidepulls because
- it has all the same problems and not the advantages. In contrast the
- cantilever is the most rigid of available brakes and offers more tire
- clearance for off road use.
-
- The approach angel moves the brake pads in an undesirable direction so
- that as the pad wears it must be adjusted to prevent falling off the
- rim. With wear, the centerpull goes into the tire while the
- cantilever allows the pad to pop under the rim, never to return.
- Cantilever brakes have the additional problem that their reaction
- force spreads the forks. For this reason, U shaped stress plates are
- made to contain this force. For forks with telescopic suspension,
- braking restricts forks motion.
-
- Nearly all bicycle brakes have about the same mechanical advantage
- (4:1) that arises primarily in the hand lever. The "calipers" all
- approximate a 1:1 ratio. This is necessary to fit the reach of the
- average hand and the strength of the hand in proportion to body
- weight. That is to say all brakes are made to about the same human
- specification. Force and motion are a trade-off and this is the
- result.
-
- The Campagnolo Delta and Modolo Chronos brakes have a variable ratio
- that at the extremes ranges from infinity to zero, its motion being
- generated by an equilateral parallelogram that changes from one
- extreme to the other. This is an undesirable feature, especially as
- the pads wear and braking takes place in the zone of increased lever
- travel and increased mechanical advantage. The brake bottoms out
- abruptly.
-
- Servo activation on cantilever brakes has been offered in a design that
- uses the forward thrust on the brake post to add force to the
- application. Self servo effects are undesirable in brakes because the
- proportionality between braking and hand force is lost. You don't
- know how much braking you will get for a given hand lever force. It
- can vary widely and in some circumstances cause an unwanted skid.
-
- ===========================================================================
-
- Adjustments and Repairs
-
- Seat adjustments (Roger Marquis marquis@well.sf.ca.us)
-
- The following method of setting saddle height is not the
- only method around for setting your saddle height but it is the
- most popular among coaches and riders both here and in Europe.
-
- A) Adjust saddle level or very slightly nose up, no more
- than 2mm at the nose.
- B) Put on the shoes you normally ride in. Have wrench ready
- (usually a 5mm Allen).
- C) Mount the bike and sit comfortably, leaning against a
- wall. Hold the brake on with one hand (or mount the bike
- on a turbo trainer if you have one).
- D) Place your HEELS on the pedals, opposite the clip, pedal
- backwards at 30+ rpm without rocking your pelvis (very
- important).
- E) Adjust seat height so that there is about:
- 1) ZERO TO ONE HALF CM. for recreational riders
- (-50 mi/wk.),
- 2) ONE HALF TO ONE CM. for experienced riders
- (50+ mi./wk.),
- 3) ONE TO TWO CM. for endurance cyclists (250+ mi./wk.),
- between your heel and the pedal. If your soles are
- thicker at the cleat than at the heel adjust accordingly.
- Don't forget to grease the seat post.
- F) Ride. It may take a couple of rides to get used to the
- feel and possibly stretch the hamstrings and Achilles
- slightly.
-
- ---------------------------------------------------------------------------
-
- Cleat adjustments (Roger Marquis marquis@well.sf.ca.us)
-
- [Ed note: You may also want to consider going to a bike shop that does
- Fit Kit and have them do the Fit Kit RAD to adjust your cleats. Many
- people recommend it.]
-
- A) Grease the cleat bolts and lightly tighten.
- B) Sitting on the bike, put your feet in the pedals and
- adjust until:
- B1) The ball of your foot is directly above or, more
- commonly, slightly behind the pedal axle and:
- B2) There is approximately 1 cm. (1/2in.) between your ankle
- and the crank arm.
- C) Tighten the cleat bolts 80% and go out for a ride.
- If another position feels more comfortable rotate
- your foot into that position.
- D) Carefully remove your shoes from the pedals and tighten
- the bolts fully. If you cannot get out of the pedals
- without shifting the cleats leave your shoes on the bike
- and draw an outline around the cleat.
-
- ---------------------------------------------------------------------------
-
- SIS Adjustment Procedure (Bob Fishell spike@cbnewsd.att.com)
-
- Shimano's instructions for adjusting SIS drivetrains varies from series
- to series. The following method, however, works for each of mine (600EX,
- 105, and Deore'). [Ed note: Works on Exage road and mtb also.]
-
- Your chain and cogs must be in good shape, and the cable must be free
- of kinks, slips, and binds. The outer cable should have a liner.
- clean and lubricate all points where the cable contacts anything.
-
- SIS adjustment:
-
- 1) Shift the chain onto the largest chainwheel and the smallest cog,
- e.g., 52 and 13.
-
- 2) WITHOUT TURNING THE CRANKS, move the shift lever back until it
- clicks, and LET GO. This is the trick to adjusting SIS.
-
- 3) Turn the crank. If the chain does not move crisply onto the next
- inside cog, shift it back where you started, turn the SIS barrel
- adjuster (on the back of the rear derailleur) one-half turn CCW,
- and go back to step 2. Repeat for each pair of cogs in turn
- until you can downshift through the entire range of the large
- chainwheel gears without the chain hesitating. If you have just
- installed or reinstalled a shift cable, you may need to do this
- several times.
-
- 4) Move the chain to the small chainring (middle on a triple) and the
- largest cog.
-
- 5) turn the cranks and upshift. If the chain does not move crisply
- from the first to the second cog, turn the SIS barrel adjuster
- one-quarter turn CW.
-
- If the drivetrain cannot be tuned to noiseless and trouble-free
- SIS operation by this method, you may have worn cogs, worn chain,
- or a worn, damaged, or obstructed shift cable. Replace as needed
- and repeat the adjustment.
-
- ===========================================================================
-
- Tools and Workstands
-
- Where to buy tools
-
- You can buy tools from many sources. Some tools can be purchased at
- your local hardware store (wrenches, socket sets, etc), while the
- special bike tools can be purchased from your local bike store or
- one of the mail order stores listed elsewhere.
-
- You can buy every tool you think looks useful, or just buy the tools
- you need for a particular repair job. Buying the tools as you need
- them will let you build up a nice tool set over time without having
- to drop a lot of money at once.
-
- Some common tools you will need are:
-
- Metric/SAE wrenches for nuts and bolts (or an assortment of adjustable
- wrenches).
- Screwdrivers, both flat and phillips.
- Metric allen wrenches.
- Pliers.
- Wood or rubber mallet for loosening bolts.
-
- Special tools and their uses:
-
- Cone wrenches to adjust the hub cones.
- Chain tool to take the chain apart for cleaning and lubrication, and
- to put it back together.
- Tire irons for removing tires.
- Spoke wrenches for adjusting spokes.
- Cable cutters for cutting cables (don't use diagonal pliers!).
- Crankarm tools for removing crankarms.
- Bottom bracket tools for adjusting bottom brackets.
- Headset wrenches to adjust the large headset nut.
-
- ---------------------------------------------------------------------------
-
- Workstands
-
- There are a variety of workstands available, from about $30 to over
- $130. Look at the mail order catalogs for photos showing the different
- types. The type with a clamp that holds one of the tubes on the bike
- are the nicest and easy to use. Park has a couple of models, and their
- clamp is the lever type (pull the lever to lock the clamp). Blackburn
- and Performance have the screw type clamp (screw the clamp shut on the
- tube.
-
- If you have a low budget, you can use two pieces of rope hanging from
- the ceiling with rubber coated hooks on the end - just hang the bike
- by the top tube. This is not as steady as a workstand, but will do
- an adequate job.
-
- ===========================================================================
-
- Riding Techniques
-
- Descending I (Roger Marquis marquis@well.sf.ca.us)
-
- Descending ability, like any other skill, is best improved
- with practice. The more time you can spend on technical descents
- the more confidence and speed you will be able to develop. A few
- local hot shots I know practice on their motorcycles before races
- with strategic descents. While frequent group rides are the only
- way to develop real bike handling skills descending with others
- will not necessarily help you descend faster alone.
-
- The most important aspect of fast descending is relaxation.
- Too much anxiety can narrow your concentration and you will miss
- important aspects of the road surface ahead. Pushing the speed to
- the point of fear will not help develop descending skills. Work
- on relaxation and smoothness (no sudden movements, braking or
- turning) and the speed will follow.
-
- A fast descender will set up well in advance of the corner
- on the outside, do whatever braking needs to be done before
- beginning to turn, hit the apex at the inside edge of the road,
- finally exiting again on the outside (always leaving some room
- for error or unforeseen road hazard). The key is to _gradually_
- get into position and _smoothly_ follow your line through the
- corner. If you find yourself making _any_ quick, jerky movements
- take them as a sign that you need to slow down and devote a
- little more attention further up the road.
-
- Use your brakes only up to the beginning of a corner, NEVER
- USE THE BRAKES IN A CORNER. At that point any traction used for
- braking significantly reduces the traction available for
- cornering. If you do have to brake after entering the curve
- straighten out your line before applying the brakes. If the road
- surface is good use primarily the front brake. If traction is
- poor switch to the rear brake and begin breaking earlier. In auto
- racing circles there are two schools of thought on braking
- technique. One advocates gradually releasing the brakes upon
- entering the corner, the other advises hard braking right up to
- the beginning of the curve and abruptly releasing the brakes just
- before entering the curve. A cyclists would probably combine the
- techniques depending on the road surface, rim trueness, brake pad
- hardness and the proximity of other riders.
-
- Motorcyclists and bicyclists lean their bikes very
- differently in a corner. When riding fast motorcyclists keep
- their bikes as upright as possible to avoid scraping the bike.
- Bicyclists on the other hand lean their bikes into the corner and
- keep the body upright. Both motorcyclists and bicyclists extend
- the inside knee down to lower the center of gravity. To _pedal_
- through the corners make like a motorcyclists and lean the bike
- up when the inside pedal is down.
-
- One of the most difficult things about descending in a group
- is passing. It is not always possible to begin the descent ahead
- of anyone who may be descending slower. If you find yourself
- behind someone taking it easy either hang out a safe distance
- behind or pass very carefully. Passing on a descent is always
- difficult and dangerous. By the same token, if you find yourself
- ahead of someone who obviously wants to pass, let them by at the
- earliest safe moment. It's never appropriate to impede someone's
- progress on a training ride whether they are on a bicycle or in a
- car. Always make plenty of room for anyone trying to pass no
- matter what the speed limit may be. Be courteous and considerate
- and you'll be forever happy.
-
- Remember that downhill racing is not what bicycle racing is
- all about. There is no need to keep up with the Jones'. This is
- what causes many a crash. Compete against yourself on the
- descents. Belgians are notoriously slow descenders due to the
- consistently rainy conditions there. Yet some of the best
- cyclists in the world train on those rainy roads. Don't get
- caught pushing it on some wet or unfamiliar descent. Be prepared
- for a car or a patch of dirt or oil in the middle of your path
- around _every_ blind corner no matter how many times you've been
- on a particular road. Take it easy, relax, exercise your powers
- of concentration and hammer again when you can turn the pedals.
-
- If you're interested in exploring this further the best book
- on bike handling I've read is "Twist of The Wrist" by motorcycle
- racer Keith Code. There is also data out there (Cycle Magazine)
- on eye exercises designed to train depth perception adjustment,
- peripheral vision and concentration. If you know where I can
- find this information please send it to:
-
- NCNCA District Coaching Office
- Roger Marquis
- 782 San Luis Rd.
- Berkeley, Ca 94707
-
-