How To Measure Cam Chain Wear

[pertonpc]

Hi Folks

I want to check the wear on my 650 cam chain. I know what the service limit is and it says it must be measured over 20 links with the chain held taught.

Here's the question -

do I measure from middle of link pin 1 to same point on link pin 20
or...
from start of link 1 (e.g. left hand edge) to end of link 20 (right hand edge)

method two will give a bigger reading.

Is there any rule or best practice on this please?

Sorry if it's a bit basic but it is me asking after all

Cheers From Mark

[zed1015]

The same point on link 1 to the same point on link 20.
Could be the the center of the pin or the end of the link etc doesn't matter as long as it's the exact identical point on both links.
If it's a roller type chain another good wear indicator with out stripping the motor is to see how far you can pull the chain away from the sprocket

[pertonpc]

Thanks very much for that help.

I will have a go at measuring it today whilst I am swapping a couple of shims over.

Cheers from Mark

[Pigford]

If in doubt, don't piss about and worry about a few quid on a chain - if it fails you could be into hundreds to repair the damage, play safe as these bikes are getting on a bit now & fatigue is also bad thing & not so easy to measure