4 mil with 28mm pwk's mx aggressive port stock cylinders

[bikersayings.com]

I am looking to get some jetting advice before I start my new motor. I just bought the 28mm pwk's and I want to make sure that I'm in the ballpark with correct jetting. I have a once bored stock cylinders (.50mm) with a new 4 mil crank and 115mm rods. Any jetting suggestions would be appreciated.

Edited September 9, 2011 by bikersayings.com

[LS3 Machine]

I am looking to get some jetting advice before I start my new motor. I just bought the 28mm pwk's and I want to make sure that I'm in the ballpark with correct jetting. I have a once bored stock cylinders (.50mm) with a new 4 mil crank and 115mm rods. Any jetting suggestions would be appreciated.

 

 

With 28s it kinda depends on which needles u have, but I'd try 48/150 for starters.

 

Edit: I should have paid closer attention to your setup. Since you are Porrted/4mil, I would say more like 50/155. But the 28s behave a little defferent depending on needle. The stock PWK 28 needles seem to need a more lean main and pilot, while the 68Js seem to like more fuel.

[nastyracing]

I have very similar set up smaller port timings w booste ports added . Everything else same u got I'm at sea level using jjh needle 4th position 52 pilot 168 main. Bike plug chopped 165 very cleanly but running hard a tad rich. I am still currently running air box hope that helps.