50cc pocket bike trouble,help?

[ZXBarber]

i have an almost new 50cc pocket bike and was just wondering why when its at full throttle it sputters and cuts out after bout 30 seconds,i cleaned the carb and replaced the plug,i also checked the fuel lines and there not pinched,fuel filter is also clean.i notice a few seconds b4 it stalls it revs significantly higher,i check the plug and its dry as whale bone,so i know its not getting its fuel for some reason,any help???

[mac90]

sounds like the float level may be set too low

you can try a larger jet if bike is running too lean or look for air leaks at manifold etc ...

[Buzz]

For more my benefit, than anything else Mac90......


Could this also be attributable to incorrect mixture setting post carby rebuild?

I had the same happen to me and was advised that I would have to reset the mixtures after doing the carby. Sure enough after rebuilding everything the bike did what ZXBarber's bike is doing, but after fiddling with mixture settings, all came good.

Regards

[RD RACING]

i would be checking the fuel cap vent hole to make sure its clear, fuel filter may look clean but could be blocked, replace if its stock, then maybe the carby for main jet blockage. when an engine revs high then dies, this is a sign of lack of fuel. remember these carbys are gravity fed and need a good flow of fuel at all times, like the old straw in the glass of water test, put the end of a straw in a glass of water and then put your finger over the other end and lift the straw out from the water, notice you still have water in the straw until you release your finger from this straw. this is what happens if your tank vent is blocked, fuel line is blocked and filter is blocked, not enough fuel to carby or engine.

[mac90]

Originally Posted by Buzz

For more my benefit, than anything else Mac90......


Could this also be attributable to incorrect mixture setting post carby rebuild?

I had the same happen to me and was advised that I would have to reset the mixtures after doing the carby. Sure enough after rebuilding everything the bike did what ZXBarber's bike is doing, but after fiddling with mixture settings, all came good.

Regards

yes but if its a stock carby you can ajust the fine mix if you move the sirclip on the jet pin down a notch or 2 for slightly more fuel