Engine stop running

[steveluppino]

Hello,

I have been riding a freshly built 80cc 2 stroke for about a week. I thought it was a real gem. It has the standard pedal start that I thought of getting a zip starter but when I saw how fast the engine would start with pedalling I did not think I should bother changing it. But after the first time the bike or the engine had the first problem I knew it was the best choice how you have to practically tear yourself to pieces testing the bike to see if the problem is fixed by pedalling it to try start it and failing every time.

But anyway, the post which is about the problem I am having with the engine is what is of most importance. The engine was running fine for a full week since it was built then on the next ride it experience it's first problem when after a short stretch of medium to high acceleration it suddenly choked and slowed to a stop (with a full tank). I replaced the spark plug (which was black with carbon) with a new one and it started first time then I rode off again thinking the problem was fixed. But after riding another kilometer the same problem reccured this time the problem was terminal.

So I pedalled the bike home to look to fix it. I put a new mix of fuel, cleaned the carby, plug, fuel flow, all good, still no success. I checked the wiring to CDI took off kill then start the engine with success except very high idle then down to slow idle eventually cut out never to start again now no spark. I sit bike upside down and spin wheel while holding a screwdriver to lead to frame andno spark. Is it possible the CDI unit is not working or broke only after few kilometers?

 

[gary55]

Hello,

I have been riding a freshly built 80cc 2 stroke for about a week. I thought it was a real gem. It has the standard pedal start that I thought of getting a zip starter but when I saw how fast the engine would start with pedalling I did not think I should bother changing it. But after the first time the bike or the engine had the first problem I knew it was the best choice how you have to practically tear yourself to pieces testing the bike to see if the problem is fixed by pedalling it to try start it and failing every time.

But anyway, the post which is about the problem I am having with the engine is what is of most importance. The engine was running fine for a full week since it was built then on the next ride it experience it's first problem when after a short stretch of medium to high acceleration it suddenly choked and slowed to a stop (with a full tank). I replaced the spark plug (which was black with carbon) with a new one and it started first time then I rode off again thinking the problem was fixed. But after riding another kilometer the same problem reccured this time the problem was terminal.

So I pedalled the bike home to look to fix it. I put a new mix of fuel, cleaned the carby, plug, fuel flow, all good, still no success. I checked the wiring to CDI took off kill then start the engine with success except very high idle then down to slow idle eventually cut out never to start again now no spark. I sit bike upside down and spin wheel while holding a screwdriver to lead to frame andno spark. Is it possible the CDI unit is not working or broke only after few kilometers?

Yes. I have seen it before. The high idle you mentioned does not seem conducive to a faulty CDI problem, but is more indicative of fuel starvation. The no spark after brief ride, then sitting for a while and spark returns does indicate a CDI problem. It is possible there is through conditions you are creating or just coincidence that there is more than one player in your problem.

 

[inspectorcritic]

Yes.
Also tug a little bit on the plug wire I have had replacement wires fall off.
Might try unscrewing you plug wire snip off 3/8" screw it back in. Also check your boot if you can run an ohm meter through the entire plug wire.

 

[steveluppino]

There is no spark at the plug, at all.

When I talked about having checked the wires I forgot to mention that the wire that joined to the kill switch (the white one) was resting on the exhaust and got scamped or burnt so i rewired or fixed the connection and it was THEN the engine fired up after the first attempt at starting it then the idle went rough, rah, rah,rah.

 

[steveluppino]

I should just change the coil then call back if it doesn't work. Hard finding parts local first time into bikes.

 

[inspectorcritic]

Glad to hear you get it running again.
I got problems with a brand new motor gazbikes warn everyone right now never buy a motor that has stamp racing motor only it a f***ing joke don't run worth a s**t.
In order to get some performance out of because it faints and chugs at 1 or 2% grade was to take off the end cap on the muffler it's loud as hell but it's only way I can get what's expected out of motor.

 

[steveluppino]

I did not say was running. Just wait for part then test. Look like coil I not ride for long but have many time restart after stall when take off for new rider. But still too short time for coil to fail from new. Anyway wait for new part, hope is a good one. I will post back with the news.

 

[Stefano]

It take long time for part to arrive, soon as come as fit then spark then start up. Must be new rider every time release clutch stall have to start too many time for new capacitor to fail too soon.