I've read where alot of guys/gals are running 42 slow jets in their 440's. At 700' or thereof, my engine builder put a 45 slow jet in my 12:1, ported, 450/450 cammed 440. I am concerned that this might be the wrong size. What should I be looking for with incorrect slow jetting. I have not yet had the chance to get a plug reading for bad weather still looms.

 

If the 45 is too big it will sputter when you take off.But as long as it dosen't do that it should be fine.I would rather have it a little rich than lean.

 

Pilot jet my friend and yes it affects 1 quarter to almost half throttle.

 

it shouldn't be a problem, I'm running a 45 on a stock motor @ 1200ft. I had a Yamaha mechanic sell it to me when I had a hard time finding pilots and he said to "dial it in" with the mixture screw. Now I can start that baby with no choke below zero!

 

Pudjumper, dont wory about it your bike is slow anyway...LOL

 

not to start a big raptor vs 400 thing again. But yesterday i was riding with a raptor and he was a little faster than me, like in mid throttle. But i could hang with him pinned on the road!! i was surprised.. wonder what a cam will do for me

everyone that was riding with us also said that i landed softer than him, and that i got a little higher.

I'll admit that i like the raptor, and it feels powerful as heck. but we were on a flat road and he couldn't hit the rev limiter in his top gear, and i was totally pinned. Should have seen the look on his face when he looked back to see that he dusted me by 3 foot, lol.

no doubt about it tho, raptor is ideal for XC

 

Hey Krzy I was just joking about his 440. Pudjumper has a bad bike. With my 12t I could not catch back up with him after the start.