Having had a new chain in my hands, i find that bending the extended chain sideways across the direction of the pins and comparing it to a new chain shows how much it has worn
Because the stretching of a chain is actually the link pins wearing, a very worn chain can be 'bent' considerably more than new one
The problem is that the gap between the two cam chain sprockets is not adjustable in any way, so once the chain has worn beyond a certain point the timing has to slip out in order to take up the slack. If some of the link pins have not worn equally then while that section of chain is on a sprocket you can have a little bit of slack, or excessively high tension, because the tensioner cannot release tension momentarily in order to allow the chain on the tensioned side to take up any inequality in chain run lengths
Another way to check is by pushing two adjacent links together and then pull them apart....sometimes you can find that one link seems to have much more free play than the rest....if you do then change the chain
If you have the chain off (any chain) you can find which is least worn by bending them and laying them side by side. These are camchains from a different bike, the top one is clearly least worn, and in fact could be new...
https://www.flickr.c...N02/7583223482/
https://www.flickr.c...N02/7583223482/
another way is to use calipers to measure the length of 10 links under tension, divide by 10 and then compare that the specified chain pitch
Edited by fixitsan, 24 October 2016 - 07:59 pm.