Will someone please explain the pilot jet and what does it do, I should know this but I dont whatever.... Also how do i change it????

05 TRX 450r

 

The pilot jet is the coarse adjustment on the mixture strength, for the idle circuit. The mixture screw is the fine adjustment after the pilot jet.
The needle and jet control the midrange...1/8 throttle to 3/4 throttle. and the main jet controls the 3/4 to wot.

 

Excellent, makes sense... I am changing it out today from a 48 to a 50,and I am looking forward to the improvement ... Thanks again for the explination

 

Just don't forget to reset your fuel screw after the install.