in automotive class last week my teacher told us an easy way to put 20 hp on a car engine was to put "roller" style rocker arm since it has less friction you get many benefits. so i was looking in my manual today and saw that there is only a roller on the cam shaft side but there are no rollers on the valve side the just slide across the top of the valve. does any one make a double roller rocker arm? or am i the first to think of this? or is the power gain not enough on the small engine? also he said that the put double roller rocker arms on the new mustangs and got 31 or 32 horse power i cant remember but it sounds like a good thing to put on my dirt bike.