Anyone know how to remove a YFZ450's airbox? I want to install the GYT-R aluminum airbox flange I purchased, but I can't get the airbox out of the quad. I pull the 4 screws out no problem, but the airbox has a breather hose connected on the lower left-hand side of the airbox. This prevents the airbox from being lifted straight out.

Any help would be greatly appreciated. My YFZ450 Service manual is little help.

-horgen

 

Just pull out the plastic fitting from the rubber boot. The hose is on the fitting. there is a rubber ring that should stay in the airbox. It is a tight fit but if you can get a good grip on the hose just pull it out. Air box will just lift out after that.

 

I installed the Yamaha's GYT airbox mod (aluminum flange and K&N air filter) before I ever took my YFZ450 out for a ride. However the quad doesn't seem to idle well. If I keep my choke on the least position the quad runs better, but not perfect. After I've completed a few laps, the quad dies every time I go into a 1st gear corner; or have to pull the clutch to roll a whoop or two.

Has anyone had to rejet after modifying their airbox with the aluminum flange and K&N air filter? I am keeping the cover on until my pipe and jet kit arrives.

Please chime in and let me know where you think the problem could be. My guess is that I don't have to rejet, I simply need to lean out the air mixture screw.

Thanks,
-horgen