Page 1 of 1

Revs good w/ no load, but dies at speed.

Posted: Sun Oct 10, 2004 8:46 pm
by jarcaf
So my dad just got our scooter running, w/ new rings and all. But when we ride it, it dies under full throttle and when we go uphill at speed. Otherwise, it's got good pull from a stop and can get going ok if you don't use full throttle. When you go downhill you can rev it up to full speed unless you throttle it, but uphill, it goes to about 5-7 miles/hour and then then it stops firing until you bring the throttle back to idle. I originally thought this was a clutch problem, since it was at speed(we've also got a new belt), but judging from the fact that it stops popping altogether, i now think it's the carb. If i put it up on the kickstand, it revs up nicely with no problems. If anyone has any ideas, comments would be greatly appreciated.
-Jarvis

Posted: Sun Oct 10, 2004 9:25 pm
by Jim
deffinatly the carb, read carb cleaning FAQ and reply if you need any help :)

Posted: Mon Oct 11, 2004 11:29 am
by noiseguy
Got an aircleaner attached?

Posted: Mon Oct 11, 2004 3:38 pm
by jarcaf
There's an oiled air cleaner on, and the snorkel is sealed up well. Is there an adjustment for the float? Could it be that it draws too much fuel than is delivered and starves itself when under high load?

Posted: Mon Oct 11, 2004 8:35 pm
by Jerry
Float level is NOT your problem. The main jet is partially clogged. Do a THOROUGH cleaning as per FAQ and it will be fine.

Posted: Tue Oct 12, 2004 10:47 am
by jarcaf
I think you're right, Jerry. It runs better when the air mixture screw is full in. That means that i'm getting a lean mixture, but the air screw cuts off air to compensate, right? I keep taking it off, but i can't find anything clogging it. I can see right through the jet, but could it be a problem w/ a bad fuel filter? I also had a totally clogged choke jet-thingy(the one in the bowl) that i cleaned out, but now it only runs good when it's cold. Thanks,
-Jarvis

Dies at speed

Posted: Tue Oct 12, 2004 7:56 pm
by Jerry
The 'choke-jet thingy' being clogged tells you the carb is dirty and you aren't fully disassembling it to clean it properly. As stated before, read and heed the FAQ on cleaning the carb. Your problems will disappear, trust me on this one......

You have to completely take apart and clean the carb.

Posted: Tue Oct 12, 2004 8:42 pm
by jarcaf
I've taken it apart several times within the last 2 days. I pulled out the main jet to inspect it, and it's perfectly clean. I can just barely see light through the air mixture hole next to the main jet(is this the idle circuit?), but i don't think that's the problem anyway. I guess it's time to scrape off the mineral deposits around the inside of the bowl. I'm gonna fit a new fuel filter on as well. Thanks,
-Jarvis

Posted: Wed Oct 13, 2004 8:50 am
by Jerry
I repeat again - if there are mineral deposits, you aren't cleaning it properly. There should be NO deposits of any kind, anywhere in the carb for it to run correctly.