Mikuni TM33/34 jetting
 

2009 Kawasaki 250s, with Bill Blue 351 kit. This would rev normally with the stock carb. With the Mikuni it Boggs down at around 8k rpm, under acceleration. Do I need a larger main air? It has the one Bill put in for sea level running.
I have never worked on this particular carb before, does it have to be removed to change the jet?

Thanks, Mick

Mick I have a 2006 with a BB 351 and TM33/34 carb from Bill with a full muzzy exhaust. I run a 40 pilot and a 145 main with no issues. I think the carb came with a 37.5 pilot and a 140 main if I remember correctly. I also have the KDX snorkle on the air box. Best to remove it to work on it.
Hope that helps.

Thanks. I removed the Airbox cover and the problem went away. Hopefully today I can go out and get some dirt on it, temps in the 50's

Mick

If it clears up without the cover, IMO, your running too rich.

Hi Mick.

i have a kit at sea level - Oakland. I have the lid on. The carb came way rich. I think due to humidity. I installed a wideband sensor so I could read the air fuel mixture.

I am currently running a 130 Main and a 35 pilot. The bike is running between 0.7 and .9 now (1.0 being lamda (14.7:1) .

i’m planning to go down a size in both pilot and main next weekend an redo my datalog runs for 1/4, 1/2, WOT.

I ran a 135 main jet and a 35 pilot with no air box lid and it was right around 1.05 - .85 which felt pretty good and made a racket lol.

Conculusions : defiantly the 140/40 setting from bill was very rich for my weather - I could see it working with a full exhaust and a k&n and no air box lid - but even then I think it would become over rich in the higher temps..

where red are you located ? What humidity? What temps ?