Pit bike fouling out plug

Hey guys, my buddy's pit bike keeps fouling out the spark plug. I have removed the carb, taken it apart and cleaned everything, put new oil in it and changed the spark plug. After re-installing everything it fired right up and runs great for about a minute, then fouls out the spark plug again. I have tried adjusting the idle, choke and throttle cable, but nothing helps.



What do you guys think it could be and what should i try next? thanks again everyone.

 

Insuficient information provided

OK Holmes, is it fuel fouled or oil fouled? 2 stroke or 4 stroke?

Fuel fouled - choke level incorrect, float valve needle/seat not sealing, air filter very dirty. Are you certain that the airscrew is adjusted correctly?

Oil fouled - needs rings, possibly stuck oil ring, valve seals leaking, clutch shaft seal is bad allowing trans oil into crankcase (2 stroke).

 

I believe you meant the crank seal. Tdub

 

It is a 4 stroke, we have ordered a nre filter just in case, but the old one still looks good and i have taken the carb apart. The floater was sticking, causing the fuel to come out of the over flow tube but I fixed that issue. But it still fouls out the plug.

I have also removed the air filter and tried runing it that way to see if it was the filter that was causing the issue, but still with the same results.


Is there anything i can do to test anything else?

 

Correct plug heat range?

 

We are using the same brand plug that came with it, we also gaped it to standards that are in the manual.

 

What bike is it?

 

chinese knock off. crf50 copy

 

there's the problem.

 

lol, I know I know, but it is what he has to work with.

 

it's the electrical system. complete garbage.
the next thing to go will be the starting mechanism.

 

So you think it is the CDI box? And it is a kick start.

 

is gas fresh?

 

If you have not done so, change the crankcase oil.
The fuel flooding out of the stuck float washes into the sump and dilutes the oil, BAD.

 

Yep, 4 sure shoulda read crank seal, not clutch.
What the hell, is this the onset of AADD? F!, made it to 48 b4 the crainial breakdown...

 

Yes the gas and oil have been changed.

 

i think it's the overall lack of quality in craftsmanship/materials. voltage leaks, inefficient windings, you name it.

tuners' post on fueled oil is on the money. pop the oil fill cap and take a whif...smells like gas? there's the current problem(all those vapors gettin' into the combustion chamber)...to be followed by the starter if the electrics stay together.

 

Check the spark. It needs to be able to jump 1/4" to run and 3/8" to run well. Just because it'll jump the plug gap doesn't mean much. Even with a cheap Chinese CDI, it should jump 1/2".

 

Yep those Chinese are pretty shrewd. They know they'll never get a cent of that 2 Trill $ back, so the plan is to drop many, many tiny bombs on us, just like these little 2 and 4 wheeled POS's...