I was messing around with the TB400 and took the top front snorkle piece off the airbox and leaned the fuel screw a quarter turn and it sure seemed to clean up the bottom end a little on it. Do you think it will be all right like that? Plug color looks good.

 

With the snorkel coming off it should have leaned out already. So really you should've richened it up with the fuel screw. But the real test is the plug. I like mine to look dark and almost wet. Just bairly under were it will foul the plug.

 

Hey Oghma, what jetting are you running with the 39 carb?

 

what do you mean when you say leaned the fuel screw? if we are talking about the same thing then that screw is an air screw. turning it out is providing more air therefore leaner. turning in is less air (richer). most screws on 2 strokes are air and on 4 strokes it meters fuel. be careful when changing your jetting like that on a 2-cycle. i'm not tyring to make you scared of doing it but keep a close eye on your plug. if you already know this info then disregard.


steve

 

Troyer233 I am running a 168 right now but need to drop down one or two more. She is waaay rich, not fouling plugs but doesnt seem to want to climb rpm's too fast. I am waiting on a new pipe before I start spending a bunch of time tuning it in.

 

in the long run the thing wich all came across the airbox thing is
if you do airbox change the jetting will suffer first then the carb fuel
bowl pressure,detonation,with stock airbox go for a k&n filter in so the
jetting should be resloved as a turn of screw,while an airbox changes or holes can create flat spot in the power delivrery,if you don't mind
i still like no airbox at all the best.

 

troyer i run a 163 main in mine and it is not to bad and the clip is second from the top if that helps?

 

I have mine with a 38 pilot, clip in the middle, and 170 main, still a little rich though. I havent got any leaner mains yet.

 

that jetting above will work with no airbox easily and better too,
very restrictive airbox,good for mudding at power loss expands.

 

i forgot about the pilot i have a 35 in it helped clean up on the bottom end