kymco super 8 50cc 2st trouble starting

[kymco@user]

Hi since it was new my moped always had trouble starting if it was a cold day or if it wasn't used over the weekend, It turns over and fires and everything it just doesn't get going and being a few years old i have to continuously put petrol in the spark plug valve to get it running. If i don't do this it won't go anywhere. Any ideas? cheers

[Chris0381]

Sounds a bit carb/choke related.

How cold are you talking about ?? Did you do any mods to the air box increasing air flow ?

Rebuild the carb or give the carb a good cleaning making care that the tabs regulating the float-ball height are set properly.

Make sure you have no cylinder head gasket leak and do a compression test on the head.

Im thinking also your jets could be possibly be partially clogged.

One idea - run 1 oz of seafoam to a full tank of good high octane gas for a few tanks.

[KYMCO2TCHLTNC]

Use the manual choke take a plastic shopping bag, put it in the air inlet, turn it over a few times to get some gas from the carb bowl, to the crankcase, from there it goes to the piston chamber and plug.

[Chris0381]

I just got mine started for the first time after winter. I actually removed the hose of the vacuum actuated gas supply valve from the manifold on applied suction to it to draw gas into the float bowl. The used a bit of carb cleaner in the sparkplug hole and it started up after a few tries.

2 things to check:

1) make sure that vacuum gas delivery valve is getting good vacuum. Make sure the hose is connected well to the manifold.

2) Make sure the valve's diaphragm is not leaking. Apply vacuum to the valve and see if the vacuum holds (ok ok Ill admit I used my tongue). A leaking diaphragm in that valve, will interrupt gas flow intermittently or wont allow it at all if the diaphragm is really bad.

Now you can remove that valve and bypass it with a hose. But the valve is a safety feature for gas cutoff when the engine isn't running. You can use a hose with a shutoff T-Valve. But the safety principle is that the carb gets no gas supply when the vehicle isnt running which could turn into a fire hazard if a leak developed and the valve wasnt in place. And during an accident if the bike shuts off, there is no gas supply to the carb once again reducing the possibility of a fire or gas leak.
The valve is also used because people forget the turn on or off the Hose-T-valve that was used on older bikes.


Any other reasons or thoughts on that valve ?

[Chris0381]

Also Im considering on of these manual choke conversions. I believe, if the choke plunger sticks up, you'll conk out eventually as the motor gets warm as more fuel is allowed into the system. A manual choke will help with some starting/running issues and allow you to say when the choke is open or not.

http://sobisource.com/gy6-manual-choke-conversion/

I put one on my 76 Chevy Nova 20 years ago.