Huasheng 4-stroke problems

R31 POWER said:

I've spent hours today reading posts on here trying to find answers for my problem. Motor is on a stand up scooter.
Motor starts beautiful with choke on. Turn it off it's still sweet. If i give it to much throttle when i take off it will stumble then come good. I put this down to it being a small engine and i can live with that.

About half throttle it will surge and if i give it more gas it's fine till just before max revs when it surges again. It has stock air filter and exhaust. Full throttle and holding it there it's fine.

This is the strange part. Every 10 minutes or so it will just bog down hard, even with full speed. It will idle rough and any throttle will make it want to stall. If i suck on the fuel bowl over flow hose and restart it it's fine Why is this?
Another 10 mins or so and it will do it again. This can happen at full speed or going really slow.

Things i've done to fix it.
- New ngk CR7HSB plug
- Full carby clean, like 7 times. Main jet is clean and all holes blown with compressed air and fine wire pushed through them
- Tried 91 octane and 98 octane fuel
- Breather hole on gas tank lid enlarged.
- Fuel hose not restricted.
- All gaskets between carby and head are gasket glued with original gaskets.

Could it be float level? main jet size? kill switch faulty?

Jase

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