Surfrjag

Those airstrikers like small jets.. without knowing more info i would still start with a smaller pilot. Maybe a 40-45. Also what needle are you going with i have had good luck with CEL on stock cylinder builds.

Leaking coolant into pipe means headgasket is leaking. Fix that 1st!

Fix headgasket leak and get some silencers and jet the thing. Probobly 280 mains

I used 3/4" diameter .058 thickness chromolly tube i got from wiksaircraft supply welded some heims on the upper bars for some adjustability. Heim sets on ebay

Start by cleaning the carbs. Mainly the pilot jets..

Seemed like getting mine right was all in the needle.

Are we using 28pwk or did i misread?

28pwk dont take the same needles so pretty sure there is no cel needle. I have n68a on 2nd clip from top and 48 pilot. What needle have you got most come wit jjh

Yes the crank usually starts to come appart when you start making power. they dont come welded stock so its a good idea to have it done

Porting is where its at on these motors. I dont think i would ever put one together for myself without it. Lol I dont see why you cant keep a 4mil motor under or around 1500

Would you consider some taller haulers? I have some that size 12pdl

4mil is a good option, if yours needs crank bearing who knows how much longer the rod bearings are going to last. Things you should need are 4 mil crank domes and coolhead Stroker pistons pancake bearing Oil seals Gaskets Adjustable timing plate porting for the 4mil Good clutch Right pipes What pipes have you got? I like pro circuits for your style of build You will be fine with stock carbs but its nice to get rid of the tors.

That and true and weld the crank saw anotherone separating today

call me crazy but I would think in a short race it would be more about your setup than getting the last 2-3 hp out of the motor

Why not decrease air pressure and increase timming?

Check it first thats not a huge change

I got a stock one for 10 shipped pm me if interested

so is the problem bogging or standing up off the line?

What size and type tires are you running?

from what I have seen the loading plays a big roll on power output. the dyno I have been using is a free spin dyno so if I don't gear the bike to do 80-100 mph it shows a really low power number. at least that's what it seems like... I think my trail bike hit 32hp.. lol

Did you try removing a spring completely?

Go weisco How could he blame the pistons?

I have seen 4 motors toasted from floats being out of wack

I dunno why I was thinking flywheel keyway. drive keyway usally leaks oil and smokes a ton out of that side. either way I would still check that your getting good fuel flow by clearing out the gas cap vent and checking float height on both carbs. leakdown with tell you if its an airleak