Seeing as it has been flogging down with rain for over a week, I thought I'd whip the wheels off as the rear Pirelli MT60 was nearly done & try something a bit more off road oriented. After the usual scouring of the web for info the local bike shop fitted a pair of 606's to loose rims for $220 (about 100quid) That'll do me thank you very much.
The normal rear size is 130/80 17 but the 606's are 130/90 17 so I'm guessing this makes the outer circumference of the wheel a bit larger effectively raising the gearing slightly. So the speedo will probably now be a bit less than 10% out?
Anyhow looking forward to getting out on them soon.