For levers i would recomend the avid SD7's the main advantage in my oppinion over the XTR levers which i have ridden before is that the SD7's hold the cable wherever you set it on the speed dial, where as on the XTR when you pull the lever if you have wound the adjuster down it slides and clunks whic is never good, so SD7's all the way, unless you can afford the ultimates As for a rear disc, i have run a rear 200mm avid on my simtra and it was VERY good, but the feel at the lever was not realy brilliant, i don't know how the new moto's compare, i am planning on putting a 203mm avid BB7 on the rear of my simtra over christmas. As for one on a mod, i am sure that a 160mm avid on the rear would be more than sufficient! Adam