Chain - uneven tightness

Hi,

I discovered the tightness of the chain for my bike is uneven (when I
parked my bike using side stand (no full stand), sometime the chain is
tight ie: no allowance, sometime the chain is loose - around 1 inch
allowance). What could be the caused ?

Brand: Suzuki
Model: GZ125


Thanks in advance,
YC

 

Chains wear, and they don't wear evenly. All worn chains have some form
of tight spot. Adjust at the tightest spot (ie: better too slack than
too tight), and if the tight spot is severe (as it is on my Ducati at
the moment, ahem), replace the chain.

 

Sprockets also wear unevenly, check the teeth for broken or worn ones.

 

True

 

The tightness of your chain can depend on the degree of compression of
your suspension - (read position of the bike).
It's a 125. Boost it up on a milk crate and check it properly with the
rear wheel off the ground.
If the tension varies when you turn the free hanging rear wheel your
chain may be stretched unevenly, but this is not too common.
Also check for play in the swing arm bearings. That'll do it too but
you'd probably spot it in the handling of the bike, (swerving on
throttle changes).
Best of luck _ Pragmatist - "R75/5 Forever!"

 

Chain tight spots will exist whether the bike is on the sidestand,
centrestand, a milk crate, or hanging from a Chinook helicopter.

What on earth are you on about?

 

Uneven tightness can be caused by a sprocket not centered on the rear hub
put the bike on the center stand and rotate the rear wheel till the chain is
at its' tightest
then loosen the nuts holding the sprocket a little and tap the
sprocket/chain forward, then tighten the nuts.
rotate the wheel and see if corrected the problem.
Wore out chains and sprockets will also have this condition and will be
worse if rotated on reverse direction.

 

Since the swingarm pivot is not coincident with the
countershaft, the angle of the swingarm will
determine the distance between the sprockets.

That's why the Buell XBs use that funky tensioner.

 

Yes, and it's why the Hesketh had the output shaft concentric with the
swinging arm pivot, but it doesn't alter the fact that if you have a
tight spot, you'll have one no matter how you park or hold the bike.

 

I have never, ever known this happen. Not saying it can't, mind, but the
difference is will make is infinitesimal compared to the amount of
"tightness" caused by a knackered chain - which is what the original
poster has.

 

I tried an aluminum sprocket on the back of my GS1100EX.
The sprocket had so much run out that I removed the teeth
in a lathe, counter bored the mounting holes, and used the
sprocket as a giant fender washer for a Zytel sprocket.
Never wore out another chain after that, although the
nylon sprocket did lose a couple of teeth by the time
I disposed of the bike.