i dont know about the shearers but i do know the cpis dont show there potential on a stock bike, they run ok but you wont notice as much of a difference as you would with some t5's, fatty's, pts, dmc's, etc. I imagine the shearers would be even worse. You have to remeber what these pipes are made for and its not for stock bikes that are puttin around the trails, its for all out balls to the wall drag racing!