Timing chain stretch/wear limit

[Jhurt]

Ok I need a spot of help...I have the factory manual and the aftermarket manual. I CANNOT find the spec for timing chain stretch limit, i.e. how many pins you measure and what it should be on a 1978 GS750. Can someone point me in the right direction...I don’t know how many miles are on this motor and it wasn’t running when i got it in. Also tried a search here and couldn’t locate the info...thanks for any help! If you have the factory manual what page is this info on? I looked twice then I had some beers and looked again ands still didn’t find it.

[tom203]

My 650 manual says.....stretch cam chain tight and measure over 21 pins...length should not exceed 157.8 mm

[Steve]

My 850 manual says just about the same thing.

It calls it the "20 pitch length", not 21. Theh difference is whether you number that first pin "0" or "1".

If you place your caliper on a pin and call that one "0", you will measure the distance to pin "20". You will be measuring 20 links of the chain.

If you place your caliper on a pin and call that one "1", you will measure the distance to pin "21". You will be still be measuring 20 links of the chain.

I mention this because this is similar to a common problem when setting cam timing.

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[Sandy]

Yes. 20 links or 21 pins. Steve, how many eggs in a dozen? 11 or 12? Just funnin' with ya.

[Steve]

Steve, how many eggs in a dozen?

ALL of them.

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