Purple - Blue Gradient

TPI Idle Adjustment Screw

TPI Idle Adjustment Screw

     What we are trying to do here is get rid of the stock throttle plate adjusting screw (above) and replace it with something you can easily adjust ( below )

improved idle adjustment throttle body TPI bike

     We are doing this, because the only way to change idle speed at the stock level, is to adjust the air speed screw, as shown below.   Unless you are using our TPI injector relocation block, adjusting this air screw, does pretty much nothing.

     Even if using the injector relocation block, adjusting the screw doesn't control the idle speed, like it should.    

     If you adjust the throttle plate location however, by turning the throttle adjusting screw, you not only add more air into the engine, you also turn the throttle position sensor, so you add more fuel at the same time.   This is the right way to change the idle speed.

Below , we'll show you how to do it.    You need a torx wrench, size T10, and a small propane torch

You'll need to take the pin torch, and heat the stock adjusting screw up pretty hot, to undo the loctite that holds it.  Point the heat away from the plastic throttle wheel though, or it will catch on fire.

Start to twist the screw, even though it probably won't come out. It's loose now, so spray some WD 40 on the threads and let it sit for a bit.  Between the WD 40 and maybe heating it up again, it will come out.  Don't force it.

     Then it will come out, and you can thread our new screw and tension spring in, and tun n far enough, to where it opens the throttle plate just a bit.

     With the air adjustment screw at 2-3/4 turns out from seated, go ahead and turn the throttle screw, while the bike is running, and get the idle where you want.

     You can adjust the idle with the throttle screw, and then fine tun the idle with the air screw, as your riding the bike, to kind of get the idle you want.  Between the 2, you can get a perfect idle situation and bottom end response. 

      The air screw can be between 2 and 6 turns out, for fine tuning. Don't turn all the way in or out past 6-1/2 


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