Home | Classifieds | Mechanic | Links | Race Headlines | Features | New Books | Photos | Travel | Cartoons | OH-WV-PA InfoSite Map | Search | Contact

Bikexchange.com logo, link to Home     Bike graphic linking to full selection of bicycling books.     Send your questions to bicycle expert Andy Wallen. (Cartoon image of Andy)Ask the Mechanic                           

Fall 2005            Spring 05Win 05 | Fall 04Sum 04 | Spr 04 | Win 04 | Fall 03 | Sum 03Spring 03 | Win 03 | Fall 02 | Sum 02
                                                                Spring 02 | Win 02 | Fall 01 | Sum 01 | Spring 01 | Win 01 | Fall 00 | Sum 00 | Spring 00 | Win  00
                                                                Fall 99 | Sum 99 | Spring 99 | Win 99 | Fall 98 | Sum 98 | Spring 98  
                                                           Win 98 | Fall 97 | Spring /Sum 97 | Win 97 | Fall 96
Please read the Ask the Mechanic Warning/Disclaimer.
Please sign our Guest Book.

 Ad for ToolKing.com

Stuck in gear and need expert advice? Ask Andy the Mechanic (a.k.a. Andy Wallen), the proprietor of Wheelcraft Bicycles of Wheeling, WV. (Please, no old bike & antique questions.) E-mail to ibike@bikexchange.com,  subject "ask the mechanic," and tell us where you live. Or, mail your question directly to Ask the Mechanic, c/o Wheelcraft Bicycles, 2185 National Road, Wheeling, WV, USA 26003. Andy will e-mail your advice and we may post it afterward (do not submit a question if you don't want your Q&A posted in a future column). Take a look at our back issues to find answers to all kinds of bike fix-it questions. 

Support Your Local Bike Shop!

Get the DVD movie all the cycling press is raving about: Hell on Wheels
"Captures the Tour's defining moments. Stunning Cinematography - High Drama - Essential Viewing!"
- Cyclingnews.com

Backyard Bike Mechanics Should Always Have a Handy Copy of ...
Bicycling Magazine's Complete Guide to Bicycle Maintenance and Repair
 by Jim Langley
Zinn and the Art of Road Bike Maintenance OR  Zinn & the Art of Mountain Bike Maintenance
both by Leonard Zinn
Urban Mechanics Who Like Their Repair Manuals With an Edge Will Love ...
How To Rock and Roll : A City Rider's Repair Manual
by Sam Tracy

Fall 2005 Q & A's (25 posted this season)


I cannot bleed my Hayes brakes. Fluid will not go into the system. I have bled these before. They were involved in a crash when I let a friend ride the bike. I am using the Hayes kit. They are old, ~'98. I tried opening the bleeder valve more, but that just resulted in leakage at the bolt. There is definitely something abnormal, here. I have taken the back one completely apart and have isolated the blockage to the lever. Fluid will go through everything else. And if I try to push fluid through backwards through the valve in the lever, it will not go. There is a fair amount of play in the lever. I can't seem to pull the "piston" back. Have you ever experienced anything like this? This is driving me crazy. I am not a novice mechanic. I used to work at the Yeti factory. While I know that assembling bikes does not make me a professional wrench, I have never run into something that completely stumped me like this.

Thanks for your help,


Sounds like you have an obstruction. Probably couldn't have figured that out yourself. This can be tough to isolate, but often originates in the bleeder, or a kinked hose. I'm not sure what Hayes suggests (you can always
call them, they offer excellent personal service, plus their guy's name is Andy), but I've blown compressed air through the caliper, replaced the hose, and had success.

Good luck,


I'm not too familiar with terms and part names. I have a Cannondale Super V 2000 (1999) and one of the pedals broke off. I was trying to change it but was stopped due to the fact that I have no idea how to take it all apart to put a whole new pedal system on it.

Thank you,


To define terms: the pedal is the part that your foot contacts (Latin, or Greek, maybe, ped means "foot") and threads into the crank arm. Most people can deal with pedals, as they can be easily replaced with a pedal wrench or
a thin 15mm or crescent wrench.  The right pedal threads in clockwise, and out counterclockwise, and the left pedal is the exact opposite.  People often refer to the crankset as "pedal", and these can be more difficult, as you will need a crank puller to remove.  However, the most common problem with cranks is the worn taper on the left arm, and when this happens, the arm is already removed, so you just bolt on a new one. 

Hope this helps,


I have a friend with a set of Vector Pros with a cracked rear hub. I too have a set and would like to be proactive in any cracks coming down the road. I have been given the runaround from Trek and cannot contact DT Swiss as a consumer about the availability of a new replacement hub, if any. Is there a hub out there that will replace a cracked Pro hub? I love these wheels and would be very upset if there was nowhere to turn to get them fixed.

Scott in NJ


Sorry, but the hub shells for these are not available. Evidently, DT Swiss made the internals, and Trek either made or sourced the shells. Bearings and such can be had, but not actual hubs.


Dear Andy

I'm changing the stem on a bike that has Shimano bar end shifters. I need to remove one of the shifters to remove/install the new stem. How is the shifter held into the bar? And, how do I remove the shifter from the bar? 



Remove the bolt which holds the shifter onto the bracket. Inside the bar is a wedge, which expands when the screw (either a 5 or 6mm allen) is turned counterclockwise. So, to get this out, unscrew (clockwise) this screw a few
turns and tap the allen wrench to dislodge the wedge. That's it.



I have a 72-inch Schwinn Giraffe unicycle that has recently begun to “slip” while pedaling up/down hill – i.e., the wheel continues its motion when the pedals are stationary. It appears that replacement parts are a little hard to come by for these bikes nowadays. Would it work to weld the sprocket? Also, the bearings need replacement – where would I find the correct type?



Most unis use a common cartridge bearing, which should have a number on it once you get it out. As for the cog situation, I have no idea how this is put together. I don't know whether a uni specialty place like www.unicycles.com
could help here. If it's already broke, a little welding couldn't hurt.



How do I prevent rusting from inside a steel frame? 

Thank you,


Back in the old days, they used to drip linseed oil, or motor oil inside the frame. These days, you can spend five times more for an aerosol called Frame Saver, which is probably linseed oil or motor oil that you can conveniently spray inside the frame. I've used this stuff a number of times, but we won't know if it actually works for several years. If rust is already a problem, I'm not sure that there is anything you can do.



Just wondering what the remedy for squeaky new brake pads on a bike rim is. 

Kevin L. Zacharoff, M.D.


Brakes squeak for a lot of reasons. Most often, this is due to contaminants on the rim or pad. If you have new pads, look for a black build up on the rim. Rims can be cleaned off safely with a Scotch Brite pad. Brake shoes should hit the rim flat when viewed from the front, and toed in so that the front of the brake shoe hits about 1-2 mm ahead of the rear. Toeing in and cleaning takes care of 90% of all brake noise. Noise is occasionally caused by loose or faulty parts, and this can be checked by checking the brake arches for sloppy movement. If there is a lot of play between the brake arch and the mounting stud, that can cause a loud vibration.



I just purchased a 2005 Cannondale Gemini 900, and on the frame it says it's made from Alcoa tubing. Is this any good? Can you explain how good it is, why, and tell me about its properties? 

I'm just wondering about the technical things about the frames, and if they're strong, etc?

James in Sydney, Australia


Alcoa is the supplier of much aluminum used in the US and elsewhere. I would imagine that, like anyone else, they make good stuff and they make crappy stuff. Honestly, I can't give you a lot of technical info about Alcoa, or the relative benefits of their tubing; however, if you are going to build a bike frame, your choices are pretty much Alcoa, or one of the Italian tubing manufacturers like Columbus or Dedaccia. I think that Cannondale uses a 6061 alloy heat treated to T6, which is pretty good stiff light stuff. I also think that C'dale does, or prior to bankruptcy, did
their own manipulation (butting and shaping) and heat treating of this alloy, which may have as much to do with its quality as does its origin. People mistakenly refer to Easton as a tubing manufacturer; they actually only manipulate existing aluminum structures, which are probably made by Alcoa.



I have an 8-speed STI that will not shift into the higher (smaller) gears on the rear. When I press the small portion of the shift lever, it just feels like there is nothing there. A friend of mine had a similar problem; he has more money than mechanical skill so he just scrapped it and bought new.


Usually when this happens, there's not much that you can do.  Other than cleaning and lubricating the shifter, they really aren't serviceable.  If you buy a new one, the only 8-speed shifters out there are Sora, which really don't work as well as 8-speed Ultegra or 105.  You can buy a single Sora shifter for about $65.



I have what seems to be a component mismatch problem.

I have a 10-year-old cross bike that I upgraded the components on shortly after I bought it.  I changed it from a 7-speed hub to an XT 8-speed hub.  I also changed out the crank and B/B to an XT crank with 22/32/44 gearing.  I was meticulous in maintaining the correct chainline when I did this.  I also put an XT rear derailleur on it.  I had to go with a Sachs front derailleur (bottom pull) because I could not get the clearance I needed with my old stock Alivio front derailluer.  I also put a set of Sachs Extreme grip shifters on the bike.

This year, my grip shifter failed so I purchased a set of the SRAM Attack 8-speed trigger shifters.  I installed the rear shifter first and it works flawlessly.  I cannot however, seem to get the adjustment of the front trigger shifter correct and I don't know if I am having a compatibility problem or not.  If I do the adjustment "by the book" starting out with the
chain on the smallest ring gear and take out the slack in the cable, I am unable to shift onto the large ring gear because the trigger feels as if there is too much resistance to move the derailleur all the way out. If, however, I start the setup on the middle ring gear, I am able to shift quite well through all three gears.  When I am on the small ring gear, though, I notice my cable is extremely slack.

I know one must carefully watch the pull ratio when working with the rear derailleur, but I thought the front ones were pretty much universal.  Am I wrong?  Do I need to find a different front derailleur?  Can you recommend one for the gear range and shifters I am working with?

Bob Ringel in Comstock Park, MI


It's always best to use the same derailleur as crank. Up till now, the SRAM derailleurs have been rather dismal, so I would never recommend them in any situation.  XT crank, XT der. Ought to work.



I have a 1987 steel Trek 560 that I would like to update with STI shifters.  I am looking to do this as inexpensively as possible.  The bike currently has downtube shifters.  The component group is all Shimano 105 (SIS), but for the front derailleur, which is a Shimano 600.  The bike front is a double and the rear a 6-speed.

It appears that that Shimano never made a six speed STI shifter.  But, Shimano did make the RSX 7-speed STI shifter.  So, I am considering going with the RSX.  Will this work with a 6-speed cog, or should I upgrade to a 7-speed?  Will I need a new rear derailleur?  Do you think I will have to spread the frame to accommodate a 7-speed cog?  Is there anything else that I am overlooking?



It may be possible to use STI shifters with your old equipment, but you'll need to go 7-speed all the way, and probably have the frame spread. Also, RSX was discontinued several years ago, and I would not buy any used
shifters.  However, you can get Sora 8 and possibly still 7-speed.  I don't think that the old rear der will work, so budget for shifters, rear der, 7-speed freewheel and chain.



This is a simple one… Have you got any tips on how to stop disc brakes from screeching when wet? It hurts my ears, scares pedestrians and makes small children cry! Nobody I have spoken to seems interested in helping – typical British reticence! 

Fraser in UK


It may be that I can't help, but here are my suggestions.  Screeches are due to a couple of causes, namely something loose and/or something dirty. If you have a small noise, say due to dirty brake shoes, loose calipers or adapters, or racks mounted to the rear stays will amplify any existing noise.  Also, you can get soft brake shoes which work better and quieter on wet brakes.


Hey Andy,

I keep hearing a rubbing sound with my front disk brake. It sounds like I have dirt either on the rotor or on the pads, so I was wondering what the best way to clean my disc brakes is. Thanks.

Mike in Oklahoma City


Denatured alcohol works for most systems.  There is a product called Disc Doctor, which I have not tried, but it is supposed to clean and condition rotors.  It may be .50 worth of denatured alcohol repackaged for $6.99, or
it may be good stuff.  Try alcohol first, then clean the brakes.



I've inherited a problem others have worked on in the past and not solved. My daughter rides a Trek 1220 she bought several years ago and it came with 46-36-26 chainrings and a 7-speed rear.  It has Shimano RSX indexed shifter/brake levers and shifting has always been a problem (two few available rear shifts without rubbing on the front derailleur).

In a previous attempt at a solution, someone fitted an Ultegra front derailleur which was really not a wise choice.  The Ultegra doesn't work well with the 46-36-26 chainrings and must be moved up the tube too far so that the chain properly clears the indentations in the derailleur cage. As a result, shifts from the middle to large chainring almost always
results the chain falling off.

One solution I can see is to simply use a barcon shifter for the front derailleur and use that to trim the adjustment to eliminate chain rub, as we all knew how to do at one time (!).  Another possibility is to find a front derailleur that's optimized for this smaller chainring setup.  A complicating factor is the seat tube is of the 35mm variety.  However, the
present Ultegra is of the bracket mount type so I could re-use the present clamp if I could find a derailleur that would fit the clamp.  Are you aware of any front derailleur that is optimized for a 46-36-26 setup and can mount to the bracket type mounting?

Floyd Sense in
Angier, NC


Only a genuine RSX der will work properly with the RSX shifters and crank. They haven't been made for many years, so you'll have to compromise.  The Ultegra is probably your best bet.  You may find it easier to just get a new crank.



I have a Cannondale F700 medium CAAD 3 frame (don't know the year). I need a shorter stem, but it appears that the clamp needs to be 1.5" which I cannot find anywhere. I removed the headset locknut and measured the tube diameter at 1.5". Am I measuring correctly? Do you know where I can find a stem that should fit?

Maggie in Grantsville, WV


You need a Coda or Cannondale stem. Profile used to make less expensive stems that fit, but I don't think that they still make them. Prebankruptcy, Cannondale offered a wide variety of lengths and rises, but I don't know
what is currently out there. For decades, Cannondale used the 1.5" steerer tubes for their Headshock. Many high end downhill bikes are using 1.5" now and it seems to be catching on.



This is highly annoying me. I want to fit a generic 3-piece crank to my Huffy Twist (don't laugh, its a light frame). Do I need standard or Euro fitting?

Many thanks,


Most bikes like this use a standard (American or Ashtabula) bottom bracket.  You can tell by looking--standard bb's don't have threads in the frame; the bearing cups are pressed in.



I have a Trek 6500 mountain bike (year 2000)--love it--but the chainrings appear soft as they have gotten bent a few times and had to be reshaped back into position. I would like to replace the crank set, but I'm having problems finding the specs on my current crank (Bontrager stock item) that came with bike.

Trek website is not helpful--can't pull up specs from older bikes. Any suggestions? Have gone to a few bike stores--everyone trying to sell something different so very confusing.



Since the bike is five years old, you probably should replace the bottom bracket. Cranks and bbs go together, so you just need to worry about shell width, which I think is 73mm, but you can easily measure this. So, get a crank with the recommended 73mm bb, and off you go. I'd put at least LX level on this bike, and if you can spring for it, the new XT is very nice.

Don't buy a square taper type unless you get it real cheap.  There's nothing wrong with FSA, Truvativ and Race Face, but Shimano cranks generally shift better.



I have a 1987 steel Trek 560 that I would like to update with STI shifters. I am looking to do this as inexpensively as possible. The bike currently has downtube shifters. The component group is all Shimano 105 (SIS), but for the front derailleur, which is a Shimano 600. The bike front is a double and the rear a 6-speed.

It appears that that Shimano never made a 6-speed STI shifter. But, Shimano did make the RSX 7-speed STI shifter.  So, I am considering going with the RSX. Will this work with a 6-speed cog, or should I upgrade to a 7-speed? Will I need a new rear derailleur? Do you think I will have to spread the frame to accommodate a 7-speed cog?  Is there anything else that I am overlooking?



The cheapest way to go about this is to buy your shifters and see what works from there.  The only drawback to this approach is, say nothing works, everything has to be replaced, and you bought 7-speed shifters.  If you have to replace everything, it won't cost that much more to go 9-speed and get stuff that'll be compatible for another month or two. Don't buy used RSX shifters unless they are literally giving them away--they were junk to start with and they do not improve with age.  In new shifters, Sora 7-speed is still available. Chances are your derailleurs will work.  I can't say about front chainwheel and front der performance, and you will need 7-speed (130mm) wheel and frame spread accordingly.



I own a 1998 Schwinn Moab 3.  I really never rode it much until a couple years ago. The problem that I am having is that I am going through a crank set every year because my teeth keep breaking off.  I only ride on easy, mostly flat trails and an occasional sled hill. The crank set I had the local bike shop put on last year has non replaceable chain rings.

I guess my question is, what do I have to do to stop having to replace this so often?  I do change gears under tension because I am not good at anticipating gear changes. Is there a good crank set that I can get that is less susceptible to tooth breakage? Also, I want to do these repairs myself--how do I find out what type of bottom bracket I have and what type of crankset I can get for my bike?  

Thanks for your help,


I've never had this problem before.  Don't get me wrong, nothing on your bike (or anyone else's), was meant to last, but these things wear out rather than break. Make sure to take a good look at your next crankset before it gets dirty. Odds are if it's a lower end Shimano crank, some teeth are "truncated," as we say in the biz. Depending on the model and year, it can actually appear as if new crank may have been attacked by metal eating rodents, but the engineers at the big S assure us that this is beneficial.

What ever your buy, get replaceable chainrings, and if you are, in fact, breaking them, look for stainless rather than aluminum.  You can't buy a stainless 42 or 44 tooth ring, but I think you can get the other two.



I was wondering if you can give me instructions on lacing a 20" BMX rim. I bought a new hub and I don't really want to pay a mechanic two do something that I can do myself, so I will greatly appreciate it if you can assist me.

Thank you,


This is not something that most people will have a high success rate with; however, I get asked enough, and it is, when you get down to it, a relatively simple process.

  1. Observe whether you have holes in the rim that are offset, left and right, or straight.

  2. Insert a spoke into a hole in the hub, and run that spoke to the hole in the rim next to the valve hole.  If the holes in the rim are offset, make sure that the spoke goes into a hole offset to the same side.

  3. Insert the rest of the inbound spokes, into every other hole in the hub, run to every 4th hole in the rim.

  4. Turn your wheel over. Find the hole in the hub that is just to the right of the first spoke you put in (next to the valve hole).

  5. Insert inbound spokes as in steps 2 and 3.

  6. Insert outbound spokes into the vacant holes on the opposite side of the hub.

  7. Rotate the hub so that the spokes pull away from the valve hole.

  8. Cross a spoke over the first 2 (3 if you are lacing 4 cross) and under the last spoke it crosses, and put it into the rim hole that is one hole away from the last spoke you crossed.

  9. Insert the rest of the outbound spokes, as above, run to every 4th hole in the rim.

  10. Insert the last group of outbound spokes as in steps 8-9.

  11. Now, this is the hard  part: True, round, center, and tension the spokes to the proper tension.  Without the proper equipment, this is almost impossible.



Do you know where I can find some parts for Spin Wheels?

Luke Short 


The same place where you can find parts for a 1927 VW.  Spin is and has been extinct for several years. Bearings should be standard issue, but axles and such would have to be modified to fit.



I have a problem with keeping the seat at the right height during a ride. It keeps slipping down, and I have to keep adjusting it. I noticed today that someone had scuffed up his seat post to create more friction. Is this a good idea? Are there any other ways to keep it from slipping? Other than losing weight :).

Thank you,


Assuming that you are using an aluminum post in a metal frame, and the post is the correct size, about all you can do is get a new clamp. You really left out some crucial info, like is this a road bike or ATB, what's it made of and what kind of post.  If you are using a quick release clamp, one real good idea is to replace it with a bolt. Carbon posts often slide when aluminum ones do not, and you have to be careful not to over tighten the clamp on a carbon post. Also, don't grease a carbon post. Check your frame for deformation of the seat tube or integral clamp if you have one.



I'm from Northampton, UK. I’ve just been trying to remove the cranks from a Marin highway one (don't know how old) using a Park CP2 crank puller. I now think that it has a splined spindle bottom bracket. Can I remove the cranks with the CP2 or do I need a different tool? Hope you can help. 

Thanks in advance,


You can either buy the CCP-4C, or Shimano makes an adapter (TL-FC15) that allows the square taper puller to work on Isis or Octalink.



I want to replace my Dia-compe brake levers (w/ panic brakes) on a Fuji road bike with a newer set, so I bought Shimano Exage Aero levers with quick release on the lever.  I have never had aero levers and I can't seem to figure out how to route the cable without creating a pinch. Do I need a special cable/housing?  I looked on Shimano's site (looks like the BL-R400) but they have no install documentation or diagrams. Can you help?



You need to have enough cable housing to go from the brake lever, along the outside center of the bar, and into the first cable stop with a gentle curve.  This averages to about 18-20" for the front, and 22-24" for the rear. Tape the cable housing to the bar, and make sure to leave enough to account for sharp turns (rear brake). The cable housing will exit in the front center of the bar, and you'll probably want new tape over it. Shimano makes these things called "caterpillars", which are supposed to covet the cable housings and make things smooth, but I never use them, just electrical tape to hold the housing to the bar until you can wrap it.



I'm wanting to put a shock fork on my 1999 GT Outpost Trail. It has a threaded headset and the diameter of the stem is smaller than what I've seen on newer ones. Could you tell me the measurements for a fork I could put on it? Also would it be possible to go threadless on this bike? How could I do that? Any input would be greatly appreciated. 

Thank you, 


You have a 1" fork, which is pretty rare these days.  The major fork manufacturers (RockShox, Manitou, etc.) haven't made any 1" threaded stuff for years. I sell RST forks for bikes such as yours, as the steerer tubes are interchangeable.  You can buy a 1" threaded steerer tube and cantilever compatible fork for about $125. You could replace your stem and headset to go threadless, but I'd expect that 1" threadless stems would be scarce.


 Please visit our sponsors.
Click Here to Visit our Sponsor

Bikers: Take a spin on these...
AirFree Tires | New Cycling Books | Gift Ideas for Cyclists

Crank on Home