I'm curious about this. I am heading to 15/42 land. Already have the Stealth 42 in the rear, and am about to order the 15 front. Problem is, lots of places list a damped and undamped sprocket. It's this: http://www.ktmworld.com/product/580330291XX.html vs. this http://www.ktmtwins.com/ktm-690-counter-shaft-sprocket-1523. Which one do I buy? One site lists the damped sprocket as "the required" piece. KTMTwins only sells the undamped one.