At the time I owned a 1KF, Honda didn't have a service limit for the chain. Has anyone checked to see if they do? (measuring links for stretch). As for the tensioner, I ran mine HARD with the tensioner rattling. But I kept it at a high idle so it didn't do it very often. Superbike Mike made a manual tensioner years ago, but never heard any reviews. Elton Fish also makes one but you will pay dearly. Don't know if he still has it, but he had a 1500cc 1000 Hurricane. If you've never talked to him, he is a genius. EFRracing.com