i have a 80cc 2 stroke. I ride it regularly. just after riding it, i went inside for a few hours and came out to start it. It only fires with the choke up, as soon as flick it down its just cranking and not firing, when i give it the throttle with the choke down it changes tone quite a bit but doesnt fire . I was first drawn to a carb problem,i checked for spark with placing it on head,and it sparked. The carb was clean, i blew through each jet,and theres nothing obstructing. I changed the spark plug, wire, and soldered connections, could it be spark ? too much resistance,e.g it fires outside, but not inside. i cant get my head around it, within a few hours it can develop a problem like this, fires quite nice with the choke up. ANY SOLUTIONS ?
Bike is only firing with choke up !
- Thread starter lilchunkyboy
- Start date
i ensured the carb and the manifold were tight, where the exhaust mounts, theres a small gap due to the frame,not sure that it matters. i recently took the head off, ensured that the head bolts are tightened down.
the jet is loose, and off centred , i took the carb apart so, I’m not sure if that’s there because I took apart the carb, or it’s been loose the whole time.
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To much oil in you're gas, dump some from tank and line, add more gas......I use 50/50 mix synthetic car oil and vegetable oil
I thought I would have to add more. The petrol in the tank looks pretty clear.
If all fails with the carb try new electrical system from bikeberry.com super magneto and stage 1 cdi ( the cheap China ones suck and China cdi)
Actually... Those pictures you posted look like the 'jet holder' inside the float bowl unscrewed (& fell out)!!
Take off the float bowl & check it out!
Take off the float bowl & check it out!
There’s a metal strainer that is supposed to be a filter, if you have a in-line filter you can remove it.
Ok, the fuel wasn’t flowing well, I checked the petcock and it was dirty.
Most petcocks have a reserve like motorcycles do, there should be two openings on the petcock with one tube taller than the other.
