Jetting suggestion and getting to the carb

Ok, I'm about 1100 feet above sea level. The bike is an '06 450F. I've tried everything with the stock pilot jet and cannot come to a compromise with it. Here's what I've done. I've turned it out to about 6 turns and the bike starts up great, sputters a bit with the throttle and deaccelleration. It won't idle. I can get it to idle when it's about 3 1/2 turns out, but it idles high. If I turn it out even another 1/4 or 1/2 it idles for about 5 seconds and shuts off.

My main problem is this: when I have it idling with 3 1/2 turns out, it has a very poor response with 1/4th throttle (didn't get above that, testing in the back yard). I can barely pull the front end up. When I have it turned out about 6 turns, even though it won't idle, the response from 1/4th thru full is perfectly how I want it.

So the question is should I go with a 45 pilot jet? Remember it's stock pilot jet, which is 42 (I believe). If I do need to rejet (I have purchased two pilots (45 and 48)), what's the easiest way to get to my carb? I took off my subframe today, because I tried the loosening of the carb clamps and turning in, so I could get to the float bowl, but it looks like what is the hot start cable is hitting the frame when I turn it. I can only turn it maybe 1/4th inch, which isn't anywhere enough to get to the carb. So, with the subframe off my intention was to get to the carb a bit easier by unattaching it and working on it while it's off the bike. Please somebody help me. Should I put the subframe back on and somehow get to the carb with it on?

everyone has gone to a 48 pilot and 170 main (at your altitude). to change the pilot i loosen both carb clamps, pivot carb maybe 5 degrees and remove pilot with a altered screwdriver i have made for pilot removal, takes maybe 3 minutes but you have to blindly know where the pilot is (try a dentist mirror to get an idea and then just feel for it) if you change these 2 jets your bike will feel incredible, responsive, no pop on decel, clean WOT

Correct me if I'm wrong, but do I not need to remove the float bowl in order to get to the jets? :ride:

I have the 06 yz450f and my elevation is approximately 1000ft. I installed a #48 pilot jet , #170 main and a tusk fuel screw out 1-3/4 turns. The bike runs perfect at the current temp 70f. When it gets warmer I plan on going to a #45 pilot and #168 main. You do not need to remove the bowl to change the jets. I purchased a tool from motion pro, and made a custom tool which allows me to change jets without rotating the carb. I live in Northeast Ohio and if you are close I can show you how to change jets.

Yeah, I'm right outside of Warren.

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