421 cub jetting, on 28pwk's

[apeik]

Ok, let me start off by saying this is very temporary, and i know 35 pwk's would be way more optimal.  This will change in a month or two after i lose wife agro in the off season. (read: im broke)

 

Im going to be running a drag ported cub on gas with 28pwk's.  Ive literally been searching for the last hour for some sort of starting point and all i can come up with is set up's for 35pwk's.

 

 I'll be running at glamis/gordon's well which is like 500 above sea level.  Currently i have 50 pilots, 158 mains and N68A needles.  I was trying to figure how the high velocity would effect how much fuel get's pulled through the jets, but it's also gonna be pretty choked down id imagine.   

 

So does anyone have any idea or any expierence on somethin like this?  Any help would be greatly appreciated

[vulvafan537240]

No idea but I'm subscribing to see what you wind up with.

[locogato11283]

162-168 main

48-50 pilot

Needle clip in the middle

Air screw .5-2.5 turns out

 

A big motor pulls fuel more efficiently than than a small motor will. These jetting specs should put you right in there. Some fine tuning once you get to your riding spot may need to be done.

[apeik]

Awesome, thanks loco, exactly what I was looking for. I'll order 48 pilots and a lineup of mains

[apeik]

And ya, buncha plug chops to get it dialed

[locogato11283]

I've owned Banshees for over 12 years and other ATVs even longer and I've never done a plug chop.

 

Regular WOT plug checks are plenty good enough when tuning.

[apeik]

Damn I'm so excited...my bike is 150 miles away at the dunes in a toy hauler though. I don't think I can go out presidents and run a dune port stock stroke when I have a set of cubs sitting on the work bench. Guess I'm gonna be wasting a day driving soon.

[apeik]

So, got all the jets ordered and all parts on their way, is there any way this will run the bowls dry with a gutted gas cap? Don't really have the 80 for a pingel, but also don't wanna lean it out. Thanks

[vulvafan537240]

Gonna run wot for long runs? If not, I wouldn't worry about it.

[apeik]

Glamis/gordons, it sucks when the drags are 1/8th mile or longer on crazy weekends, if you try to slow down a buggy going 90 might run you over. Besides that just the normal sand highway runs and duning.

[apeik]

So I went to change my jets for this setup, and I had 60 pilots in I got from a builder, thought they were 50's the whole last year, lol wtf, how did it even run/idle awesome

[JKJK]

I would agree with the jettinng recomondations.Also be cautious with any extended throttle in or beyond 4th gear.You will suck those those bowls dry very easily. Unfortunately i know this from experence.

[apeik]

Ya, I picked up a pingel, and gutted my extra gas cap, hopefully its enough

[apeik]

Fired up third kick brand new everything, so I guess the 48 pilot is close, revs almost perfectly clean except for a tiny tiny bit from zero to full throttle blip, gonna adjust the airscrews a little later

[apeik]

Don't have any room, but in first gear it won't even pull the wheels up, I think 165 mains is retarded rich, desert tomorrow, so ill have room to check it out