stock throttle is a 1/4 turn...
360 degrees X 1/4 = 90 degrees... for stock
HRC racing throttleis a1/6th
360 degrees X 1/6 = 60 degrees... for racing
the HRC 1/6th turn throttles use allen bolts to hold the throttle tgethor, whereas stock uses phillips head screws...
try adjusting from the throttle bodies them selves...you should have between 3 and 8mm of play i think(can't find my manual right now, probally under tools, parts or body work...i live in a condo, and it is full of bike stuff