Front sprocket noise after tightening chain

[bastardsquad]

I had a new front/rear sprocket and chain installed in December last year. The shifts were becoming a little notchy recently as they do when the chain tension needs tightening , so I tightened the adjusters half a turn on each side . Riding to work the next day, i noticed a whining/high pitched noise seems to be emanating from the front sprocket area, but my shifts were back to smooth/normal. Can this result from over tightening of the chain? Bike has never made this noise before and was absolutely fine before the adjustment other than slightly notchy shifts. I measured the chain slack at 30 mm with the bike on its sidestand (as per instructions on swingarm 30-40mm). Checked the wheel alignment also, the centering lines at the axle nut are the same on both sides.

I tried loosening the adjustment back a quarter of a turn, but the whining noise persists still....what can be wrong here? I've done this about 6 times on 2 bikes i've owned and never struck this problem before??

[unstuck]

Not had much experience with brrm brrm,s before.

[DrunkenMistake]

Not had much experience with brrm brrm,s before.

New Chinese model I think,
makes alot of whining/high pitched noises ..

[unstuck]

New Chinese model I think,
makes alot of whining/high pitched noises ..

Ahh, thats why I have never heard of it. In that case just squirt some sewing machine oil at it and it will be fine.

[FJRider]

Sounds like (if you excuse the pun) The sprocket bearing gone ...

[bastardsquad]

Not had much experience with brrm brrm,s before.

When you live in a tiny community like I do, broadcasting your (very distinctive) bike identity may not necessarily be a wise idea !

[unstuck]

Gotta admit that it make it harder to diagnos faults though aye, not all bikes are created equal.

[bastardsquad]

Sounds like (if you excuse the pun) The sprocket bearing gone ...

Thats what i was leaning towards, that the possible slight overtightening of the chain was putting excess stress on the bearing/sprocket shaft and causing this - I thought loosening it back would fix it, but seemingly not. Does it seem odd that the bearing was noiseless until the chain tightening was done? I would have expected a bearing to show some sign previously, not suddenly go noisy literally overnight?

[bogan]

Thats what i was leaning towards, that the possible slight overtightening of the chain was putting excess stress on the bearing/sprocket shaft and causing this - I thought loosening it back would fix it, but seemingly not. Does it seem odd that the bearing was noiseless until the chain tightening was done? I would have expected a bearing to show some sign previously, not suddenly go noisy literally overnight?

When you overtighten the chain, it is possible to put tons of force (literally) on the final drive shaft bearing. Which will wreck the bearing, loosening it won't unwreck it.
Take off the sprocket cover and inspect for play the bearing, often fairly obvious when they are knackered.

[bastardsquad]

Gotta admit that it make it harder to diagnos faults though aye, not all bikes are created equal.

*cough cough* Er6 *cough cough*

[nodrog:Me]

Got chain lube?

[bastardsquad]

Got chain lube?

Yup, gets done regularly, chain is circa 2500 kM old. This a definite whining/ high pitched noise coming from sprocket area not the regular chain on sprocket noise. I fear the bearing may well be poked - only tightened 1/2 turn and rode 22 km on it bah.

[MSTRS:Me]

If chain was loose, 1/2 turn on adjustors isn't going to overtighten it. Bearing may be toast, but it's been that way a while...you just haven't noticed it?

[unstuck]

If chain was loose, 1/2 turn on adjustors isn't going to overtighten it. Bearing may be toast, but it's been that way a while...you just haven't noticed it?

I would agree with this. New bearing time.

[bastardsquad]

Thx for the input all...seems likely that the bearing may have been on it's way and that this has exacerbated it to the point where it's now clearly audible. I was very surprised myself that such a small adjustment would do this - i've been making chain adjustments sucessfully for nearly 5 years now, and never seen this happen before. Bike has done 32,500kM - not unreasonable to fail after that distance?

Interestingly enough, no comment from bike shop on bearing play when the front sprocket was fitted only 2500 kM ago....