426 jetting?

[quadmx7]

i just got my 426 motor in today and we are going to put it on tomorrow night. iwas wondering what jetting would get me close to the right one? unfortunatly i am having to run a stock head pipe with ct slip untill my sparks full system gets here sometime next week but i need to practice this weekend.

[cals400ex]

whats all done to the motor? air box lid on or off? temperature outside? elevation?

[quadmx7]

sparks cam, sparks valve work, 12/1 compression piston, port and polish, air box lid is off with k&n filter, donno bout elevation, im in mid mississippi. temp is around 90 right now.

[KY Woods Rider]

I'd go with a 42 pilot with the pilot screw 2.5 turns out, and the stock needle in the 4th groove from the top. That should get you pretty close to where you need to be from idle up to 3/4 throttle.

The main jet is what I'm going to be purely guessing at, because the port and polish should allow for a good flow and need a pretty good size main, but then again the stock headpipe with a slip-on is going to restrict the flow just a bit. Personally, I'd put in about a 170 main (Keihin, not Dyno) and go for a test run and then do a plug check. You may have to go up a couple sizes or down a couple sizes, so you'll just have to do a few test runs and plug checks to get it correct, but a 170 should be good enough for you to do a couple test runs and figure out for certain which way you need to go.

[seven]

I have a 175 and a 42 pilot at 2500ft.

[quadmx7]

aight guys, thanks for the help.

[quadmx7]

it took a 180 main jet with 1 full turn out and she ran perfect. man this things revs so quick, i love it.