I have my bike up on a stand today doing winter maintenance. When done I started it up and put it in gear while up. Noticed a pretty severe wobble on the rear sprocket. I've never noticed any drivability issues or vibration at all. Is a sprocket that wobbles normal? I need a rear tire this winter so will have the wheel off eventually. Got 14k on the rear so balance and everything would appear to be ok. Is this something that can be corrected or don't I need to worry about it?

 

Mine doesn't do that, are all the bolts tight in it?
I would think you would trash a belt before long if it is as bad as you describe.

 

You should not have a severe wobble. Check your sprocket bolts and make sure they are tight. Not uncommon for them to become loose. If tight then look at the sprocket to be sure it is seated correctly on the wheel.
I would not ride it again until you have it fixed.

 

Not normal. Those pulley bolt are critical fasteners and might be backing out. If it were me id replace them with some new ones and some locktite. Cheep insurance. You dont even need to remove the pulley just do one at a time and if you have a tap it might be a good idea to run a tap to clean any corosion and old threadlocker out. You did say sprocket...is it chain drive.LOL.

 

Not normal!

The sprocket rides on two bearings. They could be bad but they'd have to be really bad before you'd see a wobble of the sprocket. Could also be the bore in the sprocket where the OD of the bearings fit or the axle where the ID of the bearings ride.

The only way you're gonna know for sure is to take it apart and inspect. Good thing it's winter - you've got some time to check it out.

EDIT: My explanation is for an '09 up. Not sure if the pre '09s are the same. There are no mounting bolts on the '09 and up.