scooter starts and idles fine but when full throttle it bogs By nevertoooldtoride (Read 488 times)

[nevertoooldtoride]

I have a Jonway 150cc gy6 scooter with 6,000 miles. The valves are set at .004. I have replaced fuel and vacuum lines at around 2,000 miles, spark plug around 4,000 miles and have removed the carburetor and cleaned twice. The scooter starts and idles fine but after running for about 5 minutes when I give it full throttle it bogs down, additionally every time it bogs down, the tachometer goes haywire. If I move back to 1/3 or 1/2 throttle it seems to do fine and the tach works normal as well. Any ideas?

[Alleyoop]

So the first 5 minutes will it take throttle and NOT BOG? If so it appears as tough as soon as the ENRICHER cuts off the extra fuel you have a problem. It could be a few things especially if the tach goes bananas the CDI, do you have another CDI that you can slap on and try?

Is the fuel ratio mixture out about 2 - 2 1/2 turns out? Did you check the diaphgram for rips and make sure it is on right and in the grove around the top of the carb. Cause if it is leaking it will not raise the needle and not take throttle after about 1/2 throttle position.

[cyborg]

i think you hit it Alley,,,either the CDI or the coil is going away,,,i had more than one coil go dead when warm,,,and a had 2 that went multiple fire on me midway thru the rev range,,,the first one was a ballbuster,,,found it with an oldtimie timing lite,,some kind of weird short inside it,,,but in this instance i'll put my money on the CDI being wonky,,,i'd also check the pickup for the CDI maybe it's loose and vibration is making it move around a bit,,,just a thought,,,and also another thought,,it's odd that it runs fine idle cold but as Alley said when the auto choke closes after 5 min the bike runs badly,,,,i know you cleaned the carb but did you physically see light thru the needle jet?