416 ex

[whoamack22]

ok what should my main jet be or close guess with a 416 bore, 11:1 piston stage 2 hotcam, with open airbox k&n, and powerbomb header with megamax 2 muffler, it has like 150 in it right now i think,

[whoamack22]

it just doesnt seem any different then a stock 400 ex,

[whoamack22]

also would yfz main jets work for a 400 ex?

[400exredrider]

yes they should they are just kehin hex headed jets 13 series i believe

[Colby@C&DRacing]

We need to know you elevation. but I would run a 42 pilot, 165 main and needle one clip down from stock. and yes the yfz main jets are the same style

[speedy400]

Originally posted by whoamack22
it just doesnt seem any different then a stock 400 ex,
I used to have your setup, except an added port job it was definetly faster then stock, 1st idea I have for you for some more power, get a diffrent slip on muffler, it will help rediculesly the megamax2 isnt really known for good power. Or if your money is short and you wanna keep the quietness everynow and then make yourself a diffrent endcap for the muffler, and put a hole in the middle of it. I made a bunch of them, trying diffrent variations when I had my megamax2, have fun with it. But I eventually threw a HMF slip on in.-darren