PWK keihin 28 Jetting

[D.N.K]

I want to get an idea where should I start with my main and pilot jets. My set up will be:

- keihin pwk 28mm carbs

-V force 4 reeds

-toomey t5's

-It has wisco pistons and a slight bore but I don't think that matters

-stock stroke

-stock head

I'm at about sea level to 200ft and I want to jet for around 60 degrees ambient temperature.

Any help would be great. Would 160 main be a good start? Thanks

[D.N.K]

???

[sheerider11]

160 will be rich but a safe start. You'll be dropping it down. What pilot do you have in it?

[Surfrjag]

45 pilot 155 main with n68a needle on middle clip.

[D.N.K]

Im not sure of what pilot. Ill have to check. So am I right in saying as the numbers go up it gets richer and as the numbers go down it get leaner? I guess ill start with the 160 and work down. 

[Surfrjag]

Your on the right track!

[D.N.K]

Your on the right track!

[D.N.K]

ok so i went with 158 main 45 pilot and JJH needle on middle clip.

 

when wot it don't bog, but it doesn't sound smooth. it hesitates kinda

 

and also sometime when taking off from a stop while on a hill it bogs down if i don't give it a lot of throttle. 

 

Any suggestions? 

 

also i used 1/4 inch fuel line and it is still too big (leaking), what did you guys use?

[Surfrjag]

play with the needle clip up and down and see if that fixes it. my guess is that it need to be leaned out in the midrange.

[D.N.K]

but would cause the misfire up top? lean or rich? im thinking rich cause the plug was pretty dark. 

[Coupelx]

Its probably rich.

[05colorado]

I would imagine you will end up somewhere closer to 148-150 depending on what filters your running. 

 

I had pods with FMFs running a 148 jet and my brothers with pro circuits was 150 main with pods. Both stock stoke/head and around 700' elevation.

[D.N.K]

im running stock air box with lid, no snorkel, and a uni air filter. When I find the time I will lean out the main jet to see what happens and post back with results.

[ECshee]

I run a bored .040 over, stock stroke, trail ported motor, airbox no lid w/ Proflow plate and K&N(sometimes pod filters), Pro Design Coolhead - 22cc domes, Keihin 28PWK's and Toomey T5's

 

....and im usually healthily close at 158-160 mains and 48 pilots, with whatever the stock needle is.

[D.N.K]

I would imagine you will end up somewhere closer to 148-150 depending on what filters your running. 

 

I had pods with FMFs running a 148 jet and my brothers with pro circuits was 150 main with pods. Both stock stoke/head and around 700' elevation.

I tried the 150's and it ran much much better, but not perfect. It still sputtered WOT. Tried the 148 and it now runs awesome. I'm planning on getting the bike up to temp, put new plugs in, then run it WOT in 6th and shut it off to see if what the plug looks like. I'm going to be pretty disappointed if they are not brown.