Lameness

Just curious what are the normal limits for side to side runout on road wheel. I bought a new bike which came with American Classic 420s, and the LBS (a very reputable one) claims to have trued the wheels. However, when I spin the front wheel and look down at the brake pads, I can see a very obvious side to side movement every revolution of the wheel. If I move the brake pad to where it is just barely touching the rim, I can spin the wheel and get a pronounced drag with every revolution of the wheel. Any thoughts? Is it impossible to get a road wheel perfectly true?

bjkeen

Depends on what you mean by 'perfect.' I'm not a picky person so if I can get the runout (vertical and horizontal) down to less than a mm I'm perfectly pleased. I'm not riding on glass, after all, and if the spoke tension is all about right, it should be fine.

cascade168

This question comes up frequently ("What is a properly built wheel?"). The standard for bike shop repairs is Barnett's Manual and they define it as follows:

Lateral true: no more than 0.5mm
Radial true: no more than 0.5mm
Dish: no more than 0.5mm
Relative tensioning: Spokes should all be within 5% of each other.

Any experienced wheelbuilder will tell you that meeting these specs assumes a good quality rim. That being said, I just did a wheelset with CR18 rims and they met all of the Barnett's specs. CR18's are $20 rims, so you can figure for yourself what you should expect. All rims have some variations from "perfect". There are weld seams, unwelded seams, and the like to deal with. But, if your shop can't build to standard specs, they should be telling you why.

Also, a wheel built to those specs should last for a very long time, assuming no abuse.

Scooper

I agree; if I've got a millimeter or less of lateral wobble I'm happy with it. The Park Tool "Big Blue Book" says:

"Wheel rims do not need to spin perfectly straight, with zero run out, in order to be completely serviceable. Most wheels will be adequately true if they wobble laterally less than 1/16" (1.0mm), and the rim does not strike the brake pads."

Park says the same tolerance (1.0mm) is acceptable for radial trueness.

Al1943

I agree with cascade 168. And if you can see the wobble it's too much.

Al

Mothra

It's not hard to get a wheel to +/- 0.5mm wobble, takes skill and time in truing the wheel. Depending upon which person at the shop trued your wheels, it could be a 10-year vet or a green high-school kid working on his first wheelset. Best step at this point is to learn to true your own wheels, over 90% of the work's already been done, minor tweaking and fine-tuning is all that's needed.

Dusk

No it is easy to make a wheel perfectly true! As an old "wrench" when I train new people. They need to be able to true a wheel with no movement side to side....and yes it needs to be centered on the hub. Also all the spokes need to be at the correct tension.

Take it back!

Cheers