The Bicycle Exchange's Ask The Mechanic Column

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Send your questions to bicycle expert Andy Wallen. (Cartoon image of Andy) Ask the Mechanic

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Stuck in gear and need expert advice? Andy the Mechanic (a.k.a. Andy Wallen), the proprietor of Wheelcraft Bicycles of Wheeling, WV, will steer you straight. Take a look at our back issues to find answers to all kinds of bike fix-it questions.

Backyard Bike Mechanics Should Always Have a Handy Copy of ...
Bicycling Magazine's Complete Guide to Bicycle Maintenance and Repair
by Jim Langley OR...
Zinn and the Art of Road Bike Maintenance OR Zinn & the Art of Mountain Bike Maintenance
both by Leonard Zinn OR...
Mountain Bike Maintenance: The Illustrated Manual
by Mel Allwood
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
and...
The perfect book for cyclists of all stripes and levels...
The Bicycle Book: Wit, Wisdom & Wanderings

Support Your LBS (Local Bike Shop)!

Exclusive Photo: Andy and Gary Fisher at 2006 Interbike Show

Summer 2007 Q & A's (7 posted this season, with more to come, and 1,000+ in past seasons.)

No Need to "Stick a Fork in It" Just Yet on Old Judy's
Lost Stem Screws Apparently as Specialized as the Bike--And Hard to Find
Two Truing Truisms...
Bent Rim Crimps Chances of Truing
OLD Measure Sure to Keep It True
Ultegra Should Crank With Campy Veloce Shifters/Drivetrain
Measurement/Replacement of GT Stem Should Be One Smooth Ride
Korean Backyard Mechanic Doing Right By Trusty C'dale Mtn. Bike

Hi,
I Ride with an old '97 Rock Shox Judy XC fork. The Elastomers are done and I need to replace them with something. Can you recommend some type of spring that may be compatible with this fork since Elastomers are a thing of the past?
Thanks,
Jeff Brown
Guelph, Ontario, Canada
Jeff,
You may find stock replacements at hippietechsuspensions.com, but I would get a pair of total air cartridges, which I believe are still manufactured for this fork.
Andy
Andy,
I've been borrowing my good friend's bike for some time now, a Specialized Crossroads hybrid. During the course of my use three of the four screws on the headset/stem combo have fallen out. I'd like to return the bike just like I got it. I know the easy thing to do would be to replace the screws. The trouble is nobody knows what this headset/stem is! It says right on it in big black letters--Ride Right Comfort System--with the little TradeMark symbol after Ride Right. I have contacted Specialized and local bike shops and even hardware stores with no luck. Where did these mystery screws come from? Any help from anyone would be greatly appreciated.

Thanks,
Dave

David,

I'm guessing that you need stembolts, that either hold the bar to the stem or the stem to the fork. These can be difficult to find sometimes, as the caps or heads often have to fit inside a recessed area of the stem, so it's not just a question of length, diameter, and threads. If you can't get them from a Specialized dealer, I would just get a new stem.

Andy

Andy,

How do you true a bent bicycle rim? I heard that it has to do with spokes.

Thanks,
Mike
Hobbs, Minnesota

Mike,

You can true a wheel by tightening some spokes and loosening others, but if the rim is truly bent, that can't be fixed. Truing is more of a lining up process than an unbending one.

Andy

Andy,

How do you determine the center of an Edco disc hub when truing a wheel? Do you measure from the ends of the hub itself or do you measure from the adapter that holds the gear sprockets? Your help would be greatly appreciated.

Marilyn Wilson
Palo Alto, California

Marilyn,

You would not need to measure the center of the hub to true the wheel. I would use a dishing tool, which will indicate whether the rim is centered on the hub, in any case, and the center would be measured from the overlocknutdimension, or OLD. Whether gears or discs are between the locknuts is irrelevant.

Andy

Andy,

I was wondering if I could use a Shimano Ultegra crank with Campy Veloce shifters and drivetrain. I like the Campy Veloce line better than the Shimano 105, but I am not sure if this set up would work.

Thanks. Mark
San Jose, California

Mark,

You can use the Shimano crank. If you are dealing with square taper bb spindles, you must use a Shimano rather than a Campy bottom bracket.

Andy

Greetings,

I just purchased a used GT ZR 3000 for my wife and I'd like to replace the stem with a shorter riser stem for her comfort. Can't seem to find any specs on the bike. Can you tell me what diameter would have come on this bike? It's the old threaded style. (Gooseneck). Thanks a lot. Any suggestions as to where I may find a short, threaded, riser stem?

Ken H.

Ken,

If you can fit a 32mm headset wrench on the locknut, it's a 1". If you can fit a 36mm wrench on it, it's 1 1/8". There are still stems available for both sizes in high rise and various lengths, as well as adjustable models.

Andy

Dear Mr. Wallen,

First, thank you for the fantastic forum; it has been very informative and entertaining.

My question involves upgrading an old (1991 Cannondale SM 2000) MTB. I want to add a suspension fork, with all the required upgrades, and upgrade some other components as well. Unfortunately, I currently live in Korea, where MTB is very popular, but only goes back five--maybe seven--years, and it is almost impossible to find components and qualified mechanics to help me assemble my bike. Although the Cannondale frame has a 1" steerer tube, it is in excellent condition, having been in storage for the past 7 years, and well cared for before then.

My solution for upgrade is as follows: Marzocchi 2006 MX Comp with 1" steerer option (or possibly another Marzocchi fork, using Marzocchi's own 1" steerer that is sold to replace the standard 1 1/8" steerer on their other forks); Chris King NoThreadSet 1" headset; Thomson Elite Stem (using Thomson's 1 1/8" - > 1" shim); and Shimano XTR V-brakes. All my measurements and research tells me that this set up should work, but I wanted to ask your opinion in case I am missing something. Thanks for all your help.

Sincerely,
Joseph Kim
Seoul, Korea

Joseph,

It should work, if you can get the 1" steerer for the fork.

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