425 owners post here

[stupid driver]

hey,

Who all runs a 425? if so, what is your jetting. Also, i run a fcr, 39mm carb
How much of a difference will i see with this kit. It is a fully built tc kit. I am buying the motor from quadcustoms. Anything will help, Thanks

[stupid driver]

cmon, someone has to have a 425, i just need a base on where the jetting will be, so i can order the right jets

[cals400ex]

sorry don't have a 425, but i have a 406 with a stage 2 cam. i am running 160 main, 45 pilot, and stock needle location. however, this is in a stock carb, so it may not help much.

[stupid driver]

thanks, it gives me an idea of what im supposed to be at.

Do you guys think that the main would be inbetween 162 and 185? Those are the sizes i got liein around in the toolbox

[RideRed400StYlE]

really depends on your elevation, but i run a 426 with an FCR 39 and I am not positive, but I think I have a 172 main in. but it is running rich right now. I am going to be rejetting maybe tomarrow so I can let you know for sure. it should def be within the 160-180 range though..
Just for a little more info I run
JE 13:1 comp 426 piston
GT Thunder Cam
Head is ported
no header welds
HMF pipe
lightened flywheel
and the rod and timing chain. the whole 9 yards

This vs a stock 400 is sick
I am 100% happy with the power. but you may consider changing sprockets with this kit. I am running 16 -36 sprockets and it still feels like it can pull taller gears no problem.

[skemp]

Try a 168 or 170 main with the OCEM-P needle. 2.5 turns out on air screw with 52 pilot. I am talking about the FCR carb by the way. Should get you running real close.