pe 24 carb adjustments

[jetski_dawg]

i need some help.. i have a 100cc engine that im running a pe24 on it ..im running 110 octane race fuel with a 50 to 1 synthetic oil mix.. the problem im having it seems its too lean.. i have a chrome trinity pipe that has a yellow tint near the jug(no blue).. the plug is med to light brown.. i put a 120mj in it but i dont know how to adjust for the bottom end.ive got the air mixture screw centered... its not bogging and seems to be getting enough air so i dont think carb size is the issue..thanks

[Nichols Atvs]

I think your octane is to high if this is a stock engine 93 should be fine try cutting with some 87 maybe use 1 part 110 and 3 parts 87 see if it runs better, or just try the 93 and see if it runs better.

[humboldt hills]

Exactly!!
If you ar going to userace gas, you have to advance the timing.
What do you mean by the air screw is centered?
It should be from 3/4 to 1 and 1/4 out.
Have you played with the needle clip position?

[jetski_dawg]

compresson is @180..i centered the air screw by turning it in till it runs ruff then out again till it smooths out then runs ruff then back half way....i havent tried the needle position.. how do you do that and what affect should it have.. i have the aftermarket cdi that advances the timing curve

[ecmini1]

The needle clip has a ton to do with adjustment to the carb. Moving the clip up on the needle is lean and down is rich. The needle will affect 1/4 throttle to 3/4 mainly but does effect total jetting. Octane could also be a factor but jetting is the big issue.

Your close on jetting if plug color is a light brown. Way to lean is white in color. I wouldnt jet by the color of the pipe jet to the plug color thats where the burn and heat is. Jetting by pipe color has to many factors, pipe metal, the coating process, type of coating etc. That is to missleading. Allways jet to plug color.

Drop your needle 1-2 clips and you should be close.

[jetski_dawg]

thanks for everyones help!... i moved the clip 2 positions and made a BIG difference..

[ecmini1]

Any time, Glad its running better.

Ride safe:D

[bulldogfallon]

Here is a great link for Keihin carb tuning

http://www.duncanracing.com/techfaq/Tech_keihin-carburetion-jetting.phtml

[Dirtblast]

Your main jet is for wot and the pilot jet is for the bottom. Racing fuel is for hi compression engines but not needed on stock engines. Just a waste of money. Recheck plug if you go back to pump gas. You can also change the jetting some by changing the oil mixer but med brown is good on the plug.