If you mean it's running "untrue" at low speed, it's either a bent rim or a "slipped belt", meaning that the internal structure of the tire has a problem.
Check for either a bent wheel or a faulty tire. Low speed "wobble" is an indication that the bond between the tire and the belt inside the tire may have failed. Have it checked by a reputable and qualified tire or alignment shop.
The tire needs to be balanced or the shock is dead.
Worn tire? Tire and/or wheel out of balance? Bad wheel bearing? Bent axle?
You have a damaged tire. Try rotating the front tires with the rear tires to see if the wobble switches to the back.
I would say the drve train would cause a vibration. A wobble could be from a bad tire, unbalanced tire, bent rim, bad tie rod joint.
There can be several reasons for a tire wobble on a motorcycle. Here are a few things to check. Check the tire's inflation. An under-inflated tire can cause a wobble. Even if the tire is new, tubeles tires may leak especially if there is some fault with the rim. Or there may be a small puncture. Since the wheel has just been balanced, this is hardly a cause but what if it was balanced wrong? However, wrong balance would mostly cause a vibration at higher speeds. If the tire is a rear tire, then it could be misaligned, that is to say, wrongly placed so that it is skewed. This can cause tire wobble. Damaged or warped rim or break rotor can also cause a wobble. The part of the tire that is closest to the damaged part will have a tendency to jump when it hits the road. As can be seen from this, a front and a rear wheel can have similar problems which cause a wobble but more things can potentially go wrong with the rear wheel.
could be a tire out of balance or vehicle out of alignment
A tire wobbles when the nuts have not been tightened sufficiently.
The front wheels of a car can wobble because the car's suspension is not in proper alignment. The wheels may also wobble if the rim is bent or if the tire is improperly installed
I dont think a tire will wobble unless the entire wheel wobbles.... Problems with the undercarraige could cause this. Also if a tire has uneven treadwear from a poor alignment, it could wobble. A missing balance weight, or improperly balanced tire could cause wobble. Emergency braking could leave a flat spot in the tire. Check all four tires for treadwear patterns, to see if the tire is balding in one section faster than others. Ideally it will bald from the center outwards evenly as the tire ages. If the tires look even, then most likely a problem with the undercarraige is causing the wheel to wobble (broken, worn or missing component). A tire could have internal belt damage from hitting a deep pot hole hard and cause it to wobble after.
Tire could be unbalanced, wheel bearing shot, lower ball joint bad.
Something is wrong ! - wheel may be loose, tire may be separated inside or wheel bearing is shot.