chain slack

[max]

Max, do I have it right: you removed the shocks before checking the slack? Then you checked it after first pulling the chain down?

To be clear—sometimes I take a while to understand these things—you put the bike on the centre stand and measured the gap between the swing arm and the chain (54mm). You then pushed the chain down and got a reading of 63mm. Is that right?

Did you check the actual slack from the resting (54mm) position and then from the 63mm position? If so, what was the difference?

I like your idea of having a spot on the chain guide that tells you immediately whether the chain is roughly in spec.

Sorry, i was incomplete, first check is with chain slack the way i usually like it, a bit loose ( 50 mm ) but it should be about the same as per spec, i just wanted to show what the difference between the two methods was in the first picture, the difference in the slack measurement is 63-54= 9 mm. so yes, you are right !

i then tightened the chain up per spec with the shocks as per normal, then i removed the shocks to measure how much tighter the chain would be if it was in line with both sprockets, that resulted in 8 mm less slack than spec, i.e. 25 mm between lower and upper position ( pushed/pulled ).

Just to be clear; the chain is not 8 mm shorter itself, the difference between lower and upper is reduced by 8 mm from 33 mm to 25 mm at the tightest position of the swingarm.

and last question; the slack of 50 mm (push/pull ) would have measured 41 mm ( just hanging down and pushing, not pulling ).
In the end it's just how you look at it but i have ruined a chain on the hornet 900 in quick succession by over tightening it, it was shot in 200 km, the chain on the cb1100 is now halfway the wear mark at 50.000 km.

Did the same with the cb1000r chain, found the correct spot on the plastic chain guide, push up to get the slack out of the chain in that spot where i put a small mark on the swingarm and it's done, very quick and always accurate.

Excellent effort and write up. Learnt a lot there. The fact the chain tightens by 8mm due to swingarm movement is particularly important.

That was the main reason i did the test, i have always wondered how much difference it would make, remembering that really big forces are at play when the chain is that tight so close to fulcrum ( a compound angle ) which will change with different bike designs, i actually thought it would be more than i measured, Honda did well with this one.