My cam chain idler sprocket is a wheel.

At first this didn't look like a problem until I began reassembling the cylinder block.

Holy crap.

This is how the part looked when I removed it during disassembly; I just assumed it was a wheel, not a sprocket.



So now the question:

Should I replace this with the $70 nylon replacement gear, or spend the extra $30 and go with the steel Liska gear?

Fuggit. Buy once cry once, right? The part from Liska was outrageously expensive -- $115 after shipping -- but I don't want to have to deal with this again.

Before I answer, a question for you- what type of cam chain tensioner do you have on your bike?

(Also, are you missing the two rubber blocks that go on top of the shaft, or were they just removed for the photo?)

I will be replacing the stock cam chain tensioner with a ZZR1100 unit. The stock unit is implicated in far too many failures!

I do have the rubber pads. I removed them because I will have to replace the idler gear and I wanted to keep them safe in a baggie before final assembly.

Hm.... strange. Normally, I would attribute this kind of wear to an over-tightened manual tensioner, not a stock one. How many miles did the bike have before teardown?

BUT to answer your original question, if you can afford it and you've got it open, you were right to go with the metal gear. I think the nylon was only for noise dampening purposes, so while you might get a bit more rattle, it should last a bit longer.

Yeah, I'm surprised at this but examining the manual tensioner it looks like it was locked at full extension and has zero push-back. I think it was frozen like that.

I'm not sure how many miles the bike had. The odo read 3k but I have no idea if that's accurate or not.