CJR Performance Adjustable Air & Idle Screw

This allows for an on the fly idle adjustment without the need for tools. Works with both Keihin and KOSO throttle body. Great for riders that want an easy idle adjustment or to increase idle slightly to improve low RPM throttle response. Adjust your smaller idle screw first, then use the brass air screw in 1/8th-1/4th turns to further refine the idle RPM. 

CJR Performance Adjustable Brass Air Screw 
- 100% Brass design to allow the most precise CNC machining
- Double O-Ring design for added support of the weight of the extended shaft
- Requires using the OEM air screw spring
- Knurled handle finish for easy grip
- Optional short and long version available

CJR Performance Adjustable Idle Thumb Screw
- Knurled thumb screw to allow easy idle adjustment
- Included spring to ensure tension on the threads

CJR Air/Idle Screw Combo (Both)
- Includes one (long style) brass air screw and one adjustable idle screw


NOTE: In 2014 the KOSO 34mm throttle body came with this brass air screw. Later KOSO updated the design of the 34mm throttle body and machined down a part of the idle screw area. They then recommended to use the OEM air screw. This however causes a high idle and allows too much air through the bypass passage. If you are experiencing this issue, the KOSO brass screw or the CJR adjustable brass screw would solve the problem. 

*Ensure to adjust idle with an engine at operating temperature over 140*F oil temp. 
**(OEM Default idle is 1400rpm +/-100rpm)

INSTRUCTIONS - 
Default Brass Air Screw Setting - 1.5 turns out from all the way in, 1.5-2.5 out is optimal, anything beyond 3 full turns will require bringing the brass screw back to default 1.5, make an adjustment on the throttle stop screw, then refining idle with the brass air screw again. 

If you are experiencing excessive rev hang on deceleration, the idle may be set too high or potential air leak. 

This will not work with the OEM 19mm CRF110 throttle body or Yuminashi 24mm Throttle body that uses the vertical mount air screw due to contact at the location of the intake hose.

Fitment - CRF110 using 24-34mm TB, Grom, Monkey, Supercub, CT125, Dax, KOSO 34mm TB