Chain condition evaluation---all of them

Final drive, primary drive, and timing chains.
When is it time to replace the chains?
Not so much the final drive as that is quite familiar, but the other two especially.
Individually how is the condition evaluated?
I know the old car duplex timing chain way, is this the same? What about where the slipper pads run on the links?
I'm all ears.

There are a bunch of old wives out there checking chain length slack compressed and stretched and those laying chain out to see how much it can be bent into a curve but none of those really tells ya where the links ride on the teeth in operation,
only trying to lift links out of the back side of sprockets can. Then its your call how much wear on teeth vs wear on chain you are comfy with. I get antsy to ride hard once chain links lift 1/3 out of valleys and start shopping. Chain slack or tension has no effect on this at all, only pure chain link wear state from new. Check a new chain to get the baseline judgment.

My experience only, but regarding the primary and timing chains.

Replace the timing chain anytime you are in there, which hopefuly is not very often, aside frome checking free play. The chain is pretty in expensive and you feel good afterward! The primary, my orriginal triplex had bits of roller falling off. This was a renolds brand. My reseach took me to Tsubaki as a possible better chain. I have now fitted the Tsubaki and the primary cam with a bonus timing chain, maybe that is the way they are sold? But unlike the reynold chain design of rolled split outer rollers, the Tsubaki used soid rollers, this makes me feel more confident about bits of roller breaking off.
My bike had 20,000 miles showing when I noticed the primary chain failing.
Cheers Richard

My bike had 20,000 miles showing when I noticed the primary chain failing.
Cheers Richard

Click to expand...

Pray tell how did you detect primary chain failing?

stockie2 said:

My experience only, but regarding the primary and timing chains.

the reynold chain design of rolled split outer rollers, the Tsubaki used soid rollers, this makes me feel more confident about bits of roller breaking off.
My bike had 20,000 miles showing when I noticed the primary chain failing.
Cheers Richard

Click to expand...

I agree with the comfort level in the rollers made from tubing vs rolled strip. That's logical.
I am a long way from 20K so that is yet a distant milestone.
I suspect the current primary is OE but will take a look at the rollers in the AM to be sure.
Maybe the change interval should be a chain with every sprag disintegration ha ha.
Thanks.

Mr Hobot, the idea of comparison to a new chain is a fair one and most probably what I will do for a baseline. I have it all unzipped anyway.
All the best.

I agree with replacing the primary chain when you find bits of roller in the bottom of the case. Actually I ran mine 'til the end of the riding season like that (2 rollers that fell apart in different places) before I replaced it.