Jetting suggestions..

[Zbskater400]

I need some help. Blasters leak free new rings , reeds , gaskets etc. Floats set around 20mm to 21.5 and it bogs and sputters a little around 3/4 to full throttle it's got a 3mm stroked crank 67mm piston, fmf with toomey silencer lid off (still have the lid).... my elevation is 670-700 ft... I have a 270 main in it and 32.5 pilot.. trying to solve the bog/ sputter issue and need some advice where to go with jetting. The only jets I have atm are a 270 , 300 and 320 I tried the 300 and it did seem better but it was rich.. it gets around 40-45 degrees but varys each day can be warmer or can be colder... Id rather be jetting for slightly warmer weather but need you guy's thoughts on what I should do to overcome this problem and get my bike running crisp

 

[Awk08]

I have a 270 main in it

there's your problem, 270 is too lean for these temps and your low elevation.
with FMF's (pipe = biggest factor in jetting) we run 300+ here in these temps and 1800' elevation. your lower elevation will require richer jetting
I'd be throwing a 320 in there to start and see what a plug chop tells you

 

[Zbskater400]

there's your problem, 270 is too lean for these temps and your low elevation.
with FMF's (pipe = biggest factor in jetting) we run 300+ here in these temps and 1800' elevation. your lower elevation will require richer jetting
I'd be throwing a 320 in there to start and see what a plug chop tells you

Hmm sounds about right. I had the 300 main in earlier today and it still had that bog to it.. so I went back to the 270... but now I know I need a bigger main, any needle clip suggestions and pilot with my mods and temps etc ? I believe it's on the stock position and my pilot is 32.5

 

[Awk08]

32.5 pilot and needle on the middle clip has worked on every stock carb i've tuned from stock to ported and modded, with most pipes, except I hear the DMC wants riicher ?
FMF's with mods want 290 + depending on elevation.

 

[Zbskater400]

32.5 pilot and needle on the middle clip has worked on every stock carb i've tuned from stock to ported and modded, with most pipes, except I hear the DMC wants riicher ?
FMF's with mods want 290 + depending on elevation.

Awesome thanks for the advice awk I saw that post about you mentioning that you never needed to change needle positions or the pilot but wasn't sure because of my elevation I'll throw the 320 in tomorrow and see how it goes.. and I should probably double check my float height.

 

[Awk08]

in this order.....
1. float height
2. pilot/airscrew tune for highest idle, fine tune 1/8 or less turns while riding till it revs to 1/2 throttle clean. you may tune it daily for differing temps, usually less than 1/2 turn.
3. needle usually on middle clip...........
a good jetting experience is to lower clip one position at a time till you feel it rich bog, then back up one position. (lower clip = raise needle = richen)
or 1/2 throttle plug chop each clip position
4. plug chop main jet last.

you must...start at the bottom and work up.

 

[Zbskater400]

in this order.....
1. float height
2. pilot/airscrew tune for highest idle, fine tune 1/8 or less turns while riding till it revs to 1/2 throttle clean. you may tune it daily for differing temps, usually less than 1/2 turn.
3. needle usually on middle clip...........
a good jetting experience is to lower clip one position at a time till you feel it rich bog, then back up one position. (lower clip = raise needle = richen)
or 1/2 throttle plug chop each clip position
4. plug chop main jet last.

you must...start at the bottom and work up.

Nice info, thank you I will give it a shot tomorrow and update

 

[Oneshot]

Toomey recommends atleast a 310. Hope the 320 works for you.

 

[Zbskater400]

Toomey recommends atleast a 310. Hope the 320 works for you.

Thanks man I hope so.

 

[Awk08]

fmf with toomey silencer

FMF pipe determines jetting, toomey silencer don't matter much at all

jetting suggestions from any manufactuer, including the factories, are for normal summer temps.
lower elevations and colder temps both require richer jetting.

 

[Oneshot]

Ok so I get this right. The silencer is at the rear? And the pipe is coming off the head? I am still a little puzzled about which is which.

 

[dirtysquared]

Ok so I get this right. The silencer is at the rear? And the pipe is coming off the head? I am still a little puzzled about which is which.

Yes sir, your correct.

 

[82cutty]

I have an FMF...Toomey silencer...KOR ported and Head mod motor . Stock carb no lid..K@N filter I have a 330 main in it now . I did a plug chop a 35 degrees and it was perfect . My elevation is 500-600 feet . Runs like a top . Last summer 300-310 was good

 

[Zbskater400]

I have an FMF...Toomey silencer...KOR ported and Head mod motor . Stock carb no lid..K@N filter I have a 330 main in it now . I did a plug chop a 35 degrees and it was perfect . My elevation is 500-600 feet . Runs like a top . Last summer 300-310 was good

Sounds like yours and my jetting should he somewhat close to eachothers, thanks for that information.

 

[82cutty]

Yeah throw that 320 you have in there . Start with the air screw at 1 1/2 turns out...should be pretty good for 35-45 degrees

 

[Zbskater400]

Yeah throw that 320 you have in there . Start with the air screw at 1 1/2 turns out...should be pretty good for 35-45 degrees

Will do... I'll update tomorrow on how things go.

 

[Zbskater400]

Update... awk or anyone can chime in I did a plug chop with the 320 main and this is what the plug looks like. Let me know on you guys tbought on roughly where I'm at or how close

 

[82cutty]

Looks good

 

[joeak47]

Looks good! You could even go a tad leaner.
How does it run? What temperature was/is it when you plug chopped?

 

[Oneshot]

Still bogging and sputterin zbskater?