Jetting change

Tonight I decided to try a #42 pilot in the 07 yz450 to try and get rid of an annoying slow speed gurgle and to get at the carb on these bikes is crazy.I decided to pull the sub frame and the bottom off the carb and managed to install the jet but had to then take out the top shock bolt to get the boot back on the carb.I did manage to get it all done but may have lost my soul from all the cursing,now I look in the stickies and find a post about changing the jets without taking off the carb.The pqperclip thing was a good idea but are you changing these jets with the bottom on the carb and working through the plug at the bottom?If not and the bowl is off then the jets are easily removed and installed without using these special tools.Guess what I really want to know is if its possible to remove the pilot trough the bottom plug in the bowl,this would make life a bit easier when changing them out.

Yes, it's entirely possible to change the pilot with the bowl on, through the bottom plug. Easy? No. Requires patience, familiarity with where the jets are, and a good bit of manual skills, but it's faster and simpler than removing the carb.

If the pilot has never been removed before, it can become stuck pretty fast, and it's extremely important to use a screwdriver that really fits the jet correctly, and to use caution not to tear up the slot in the jet.

Here's a tip on getting the air boot back on when the sub frame is removed: Unbolt the air box from the sub frame (4 bolts). With the air box free, it can be slid into place even with the shock bolted in. Clamp it onto the carb and then slide the sub frame back in place over it.

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