[hokieSV650]

I just got a new front tire put on this past Saturday (Conti Road attack). Now when I am going 50 mph or above and take my hands of the bars slightly i notice the bars shake back and forth. I have not been over about 70 since then and want to get it fixed ore figure out whats up before I ride to much more. It is possible it has done this the whole time ive had the bike but i just know am confident enough to take my hands off the bar at 50+ mph. The bike has never been down.

I checked and they put a new weight on the tire so im guessing the idiots balanced the tire and rim correctly.

What could be causing this? Ss there a way to measure and check how straight the front end is?

 

[terryb]

Don't ride over 50 mph with no hands........????????

















Seriously, take it back RIGHT AWAY & have them check balance & proper front wheel installation. If you still have the shimmy, let us know. You shouldn't have it.

 

[orangegilly]

I got a bad tire one time a few years ago that exhibited the same wobble. Disappeared after I replaced the tires after less than one season. I would follow the advice above, though, as you shouldn't have a wobble on new tires if you didn't have one before.

 

[hokieSV650]

Yea i plan to take it back next Saturday, its the only time I can. I was just looking for things in the meantime. I'm a mechanical engineer so I understand how bikes work and i can fix pretty much anything.... i just want to know what to check for or how to measure the front end to make sure it is square.

I tried checking the wheel balance while on the bike but the wheel does not spin freely enough, even with the calipers off.

And by taking my hands off i really mean loosing my grip on the bars so my hands are still around the bars just not really holding on to them. It is also slightly noticeable with one hand on the bar.

 

[hokieSV650]

so google has a lot of stuff on front end wobble... a lot of cruiser type bikes too actually. should have googled it first i guess

This is one good site on front end wobble

 

[terryb]

Since it just appeared, it's probably bad tire, bad balance, tire not properly seated.
Shake or shimmy can be caused by lots of things, though. Rear wheel alignment or balance, improper suspension adjustment, so if the tire installer doesn't fix the problem, we'll keep at it until we get you all fixed up.

Keep us posted.

 

[sdobbs20]

there's a variety of possibilities.

bad tire? bad balance? mounted tire wrong? forgot a spacer? didn't tighten everything?