Getting your stock (fixed and loctitied in place ) idle adjustment screw out of your TPI throttle body, and using our simple adjusting bolt, is one of the biggest improvements you can do. Finally you can raise your idle, with the twist of a bolt. You can set your idle to the speed you like, and then adjust how lean or rich your idle and bottom end is, with the idle air screw. If your bike is stock or has our TPI relocation block, this is a required mod. By the way, it's just a bolt and specific spring to hold the bolt form moving.