I fitted a 525 kit from OTR a year ago. Too early to tell whether it's going to last any longer, although I haven't had to adjust it much in the last 6000 miles, other than to take up the initial stretch. Mind you, I did get nearly 25K miles out of the OE chain, quite probably thanks to a Scottoiler being fitted since the bike was new.

I went for the 525 on the basis that I had read a few reports that the sprocket carrier bearings and cush rubbers lasted longer, as well as the chain itself.

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