chain tension

hi I was wondering what is the best way to check the chain tension. I just replaced the the rear wheel after getting a puncture,and I was hoping that if I did'nt move the chain adjusters it would just go back to the original setting.Wrong . The chain seemed too tight. I have now adjusted it so that I have 30mm of play with my partner sitting on the bike, but with no one on the bike the chain is resting on the chain buffer on top of the swinging arm. Is it best to measure the chain play with someone on the bike or off the bike?? With someone on the bike the chain lifts about 25mm and drops 5mm. will this be ok? Any input appreciated.

Normal adjustment, and as described in Hanes, is to have no one on it but on its side stand. Measure the give at the mid way point along the chain on the under side of the swingarm. It would be a good time to give it a thorough check for tight spots and give it a clean too.

Thanks for that. my only concern is that when you sit on the bike the chain is going to get tighter and I am not a heavy guy, and on an uneven road surface or big bump the chain is going to be under additional stress. However I will adjust the chain on the side stand and see how it goes . Cheers.

[Luckypants]

The chain slack is intended to be adjusted on the side-stand. Read it in the manual... The recommended slack will take account of the chain tightening under load and won't cause a problem.

As already suggested take the opportunity to clean properly with paraffin then adjust, a build up of crud can cause the chain to tighten, so now is a good time to get the chain sweet.