Topic: chain wear (or not?)

[CoachDoc]

I installed a new chain and sprocket set on my 550 (stock set up) 3700 miles ago. At first I was pleasantly surprised how long the chain could go between adjustments in slack. Lately however the chain seemed to be wearing way faster and I was having to readjust slack/tension every few hundred miles.

So today I'm installing a new chain and sprocket set, thinking my last chain (D.I.D.) had been a huge disappointment. However I was surprised when I measured the chain when held in a stretched position. 20 links measured exactly 12 1/2 inches, which is exactly what a 5/8" chain should spec at. Confusing. I tighten the axle per torque spec, and the adjusters and locknuts are in excellent shape.

Could it be the sprockets that are responsible for the wear and increase in slack?

[kghost]

Yes sprockets do wear.

It's difficult to measure chain wear without tension on the chain.

[CoachDoc]

Yes sprockets do wear.

It's difficult to measure chain wear without tension on the chain.

True, to test a chain for wear it needs to be held in fullest extension under tension, which is what I did.

[kghost]

So.....how did the sprockets look?

[CoachDoc]

So.....how did the sprockets look?

The profile of the teeth shows some wear on the rear sprocket, but you'd have to have a huge amount of sprocket wear before it would be diminished in diameter enough to affect chain tension, and I don't really see that degree of wear. I've measured other chains after use in the past, and the 20 link run usually measures about 12 3/4 inches or slightly more, which is about 2% elongated. In a way it's amazing that this chain shows no elongation at all.

[kghost]

It can still wear on the rollers fairly significantly. That coupled with the sprocket wear sure can make a difference.