It is a air bleed adjustment screw used to adjust the amount of air mixed with the fuel metered by your pilot jet. Your pilot jet sizes are nowhere near what I use but your carb may use different jets than mine. I have 5 mini bikes that use those carbs from hs50’s to predators. The main jets range from 120 on the hs50 to 130 on the clones. Pilots are the stock 15.
MIKUNI (CHIKUNI) 22MM TUNING PROBLEMS
- Thread starter Saint Mason
- Start date
- Tags 196cc 22mm mikuni bt200x carberator chikuni coleman mikuni vm22-133
It is a air bleed adjustment screw used to adjust the amount of air mixed with the fuel metered by your pilot jet. Your pilot jet sizes are nowhere near what I use but your carb may use different jets than mine. I have 5 mini bikes that use those carbs from hs50’s to predators. The main jets range from 120 on the hs50 to 130 on the clones. Pilots are the stock 15.
Here in Netherlands I am just above sealevel. Fuel is Euro 98. I don't know how that compares to American fuel, but the 98 octane number is measured in a different way as it is measured in America.
https://motocrossactionmag.com/ask-...ave-so-much-more-octane-than-american-fuel-2/
https://motocrossactionmag.com/ask-...ave-so-much-more-octane-than-american-fuel-2/
I put a 22mm chikuni on my Hs50, use a 95 main jet and the bike is a beast.
I think it depends on a lot of variables.
Engine ported, cam, springs, intake, exhaust, flywheel, rod, piston, bore.
The clutch, the T/C and how they are set up. The size of the wheels, tires, wheelbase, strictly street or off-road, the weight of the rider, gear ratio etc.
I don’t think there’s any special sauce that applies to all bikes.
just imho, ymmv
I think it depends on a lot of variables.
Engine ported, cam, springs, intake, exhaust, flywheel, rod, piston, bore.
The clutch, the T/C and how they are set up. The size of the wheels, tires, wheelbase, strictly street or off-road, the weight of the rider, gear ratio etc.
I don’t think there’s any special sauce that applies to all bikes.
just imho, ymmv
I have had a Chikuni that wasn't tuneable, too. Tried everything, pilot jet sizes, needle clip heights, main jets, air screw, etc.
Solved it all at once by adjusting the float height. Now I always check float height before I start messing with jets.
I don't know how high the float level should be, but I do know when it is to low.
Chikuni is now a good tuneable carb.
Solved it all at once by adjusting the float height. Now I always check float height before I start messing with jets.
I don't know how high the float level should be, but I do know when it is to low.
Chikuni is now a good tuneable carb.
25mm... measured from bottom inside or outside?
I have set it to approx 3-5mm below the flange. Where the (I don't know the name of the part) "float bucket" meets the carb body.
I had problems if it was 10mm or so. Obvious because the pilot jet was just barely in de fuel level. Hard time starting it sometimes.
I have set it to approx 3-5mm below the flange. Where the (I don't know the name of the part) "float bucket" meets the carb body.
I had problems if it was 10mm or so. Obvious because the pilot jet was just barely in de fuel level. Hard time starting it sometimes.