mikuni sbn 44 jetting

[Sal]

i'm in search of a jetting kit for my carb. I have a kawasaki 650sx
with a mikuni sbn 44 carb. Where can I pick up a jetting kit that has
a variety of main/pilot jets, springs and needle seats.

currently my ski has a hesitation going from idle to wot. I usually
have to goose the throttle a bit then it's fine.

current jetting has me at

100 pilot
140 main
2.5 needle seat
115g gold spring.


I think the pop off is too high. The engine used to have high
compression heads and had to be run on race fuel. Last year I had the
top end rebuilt and now it has stock compression so I can run it with
pump gas. I think this is the reason the jetting is way off.

I'd like to start with a mikuni stock setup and than adjust from
there.

Low speed jet (pilot) 100
High speed jet (main) 125
Needle valve 2.3
Arm spring 65 gram

if you need to e-mail me I can be reached at
***@adelphia.net remove the no spam


Sal

[Waveblast9]

Hmm..if you bring a modded boat back to stock and you are talking pop off, you
want to raise the pop off not lower it.. when you mod a boat, you lower the
pop so you want to go in reverse.. if its all stock now.. why not just go back
to stock specs and start from there.. or go up one jet size from stock and see
how it runs?

[Sal]

i guess the problem is I'm a third owner of the jetski and in it's
past I think the jetski has raced. The carb settings that I have now
I do know aren't right. I have to test the pop off so I can get
accurate measurement from it.


i was going by this chart from the sbn manual.

http://www.mikuni.com/pdf/sbn_manual.pdf page 15.

that would put me at 19psi (goldspring and 2.5needle seat)
I thought for more bottom you want lower popoff. If I went with the
stock mikuni settings I would get 15psi and totally different jetting.
I might have the pop off right and the jetting totally out of wack.

opinions?

Sal

Post by Waveblast9
Hmm..if you bring a modded boat back to stock and you are talking pop off, you
want to raise the pop off not lower it.. when you mod a boat, you lower the
pop so you want to go in reverse.. if its all stock now.. why not just go back
to stock specs and start from there.. or go up one jet size from stock and see
how it runs?

[Rob Munach]

Post by Waveblast9
Hmm..if you bring a modded boat back to stock and you are talking pop off, you
want to raise the pop off not lower it.. when you mod a boat, you lower the
pop so you want to go in reverse.. if its all stock now.. why not just go back
to stock specs and start from there.. or go up one jet size from stock and see
how it runs?

I don't think changing the compression will affect pop-off
significantly. I believe only mods that affect restriction will.