Do i need the bearings done, could it be the cones are recked and how many ££££ will it cost?
2007-04-09 05:59:30 · 9 answers · asked by Anonymous in Sports ➔ Cycling
Chances are that the rim is out of alignment.
Lift each tyre off the ground and spin it. Look at it from above and make sure it is not wobbling. There also might be a flat section in the rim, which you would slightly feel when riding slowly.
The easiest thing to do is take it to the bike shop. They can tell you what is wrong with the bike. Tell them it is shaking when you go over 20mph, but do not mention anything about bearings. Suggesting an expensive problem opens the door for them to take advantage of you.
2007-04-09 06:37:23 · answer #1 · answered by Andrew W 3 · 0⤊ 0⤋
It wouldn't be defective bearings casuing the wobble. As noted previously, it's likely the problem is an out of true rim. Most shops will fix this rather cheaply. You also might consider new, better tires. It might not help, but it certainly won't hurt, and it will make the bike feel alot better under you.
Also as noted, the headset might need a tweak. A loose headset alone will not cause this though.
As a last bit of advice, inspect the frame carefully. If you have a crack in one of the welds for example, it could easily cause this.
If it _is_ a speed wobble, it's caused by the dynamics of the whole bike/rider combination reaching a speed where the rotation of the wheels and the shifting of the weight caused by wheel and frame misalignment become sympathetic to each other and start to behave like waves in a pool. The physics of it are somewhat complicated. but suffice to say that changing almost any variable will change speed at which it occurs. A heavier or lighter rider on your bike might not experience it at all. I race with a guy that used to have it happen to his full-carbon frame and trispoke wheels. He put on a different set of wheels and it stopped. I rode his tri-spokes on my bike and had no problem.
So. have the wheels trued, the headset snugged up and have the frame inspected carefully. If it still happens get new wheels. You don't need to spend a fortune, just get something different.
2007-04-09 16:52:41 · answer #2 · answered by MadMonkey 5 · 0⤊ 0⤋
This may be what's called "speed wobble" or "shimmy"
It can be very difficult to diagnose / fix, but there are some likely places to look
- wheels / tires true and mounted correctly
- headset adjusted correctly
Do let the shop have it for a test ride, before and after recommended repairs, and get a clear agreement that you're paying them to fix the shimmy, not to replace parts - so don't pay for new parts that don't fix it.
One counter-intuitive approach that may work is to slightly over-tighten the headset. Just a bit to control the shimmy, but not so much that it affects or is even noticeable in normal steering / riding.
Good luck
Scott
2007-04-09 14:24:39 · answer #3 · answered by scott.braden 6 · 1⤊ 0⤋
I suspect the shaking is either caused by a bent rim. However, it could be a frame that is out of alignment. That would be bad news. What kind of bike is it? I'd take it to a shop and have them test ride it.
2007-04-09 14:20:15 · answer #4 · answered by Jay P 7 · 0⤊ 0⤋
Make sure your fork bearing are not loose and if you have spoke reflectors take them off, they throw the wheels out of balance big time when in motion.
2007-04-09 17:43:54 · answer #5 · answered by wheeler 5 · 0⤊ 0⤋
Bent rim, bearings need to be replaced to if they've collapsed to much, if you don't the wheel will roll side to side.
2007-04-09 19:17:16 · answer #6 · answered by Anonymous · 0⤊ 0⤋
high speed wobbles
2007-04-09 22:39:09 · answer #7 · answered by max c 1 · 0⤊ 1⤋
maybe you are shaking it?
2007-04-09 13:06:41 · answer #8 · answered by czechoslovakian67 3 · 0⤊ 2⤋
maybe its just nervous!!!!
2007-04-12 18:28:56 · answer #9 · answered by Damian 1 · 0⤊ 1⤋