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Interesting problem with throttle

Posted: Fri May 05, 2006 6:01 pm
by Farfignugin
Here is something interesting that I can't solve but maybe someone here can:
When at wide open throttle, going down a hill, or just plain accelorating... my scoot seems to die down (like when you let off throttle), but when I let off the throttle a little it accellerates like crazy.

Could this be due to too small of a main jet? Or is it something else?

Please help soon, as this thing confuses me a lot...

Thanks in advance.

Posted: Sat May 06, 2006 7:34 am
by myhonda
u dident put the throtal on the left side instead of the right side did u?cause if the trotal is on the left its backwards on the right its normal.

Posted: Sat May 06, 2006 8:12 am
by Farfignugin
what?...no the throttle cable is fine and everything

Posted: Sat May 06, 2006 10:36 am
by hondaman
When you turn your throttle grip does it snap back when you take your hand off of it. If it does not then you have a weak throttle valve spring.
This may be whats causing your problem.

WOT

Posted: Sat May 06, 2006 12:40 pm
by DENMANSHAFFER
ITS OBVIOUS YOU HAVE TOO MUCH AIR OR TOO LITTLE FUEL. YOU CLOSE THE THROTTLE (REDUCE THE AIR) AND IT RUNS FINE. TRY RAISING THE NEEDLE VALVE UP WHICH WILL ALLOW MORE GASOLINE INTO THE MIXTURE AND SEE IF THAT HELPS.
TO RAISE THE NEEDLE, YOU MOVE THE CLIPS ON TOP OF THE NEEDLE TOWARD THE BOTTOM. DO ONE LEVEL AT A TIME.

IF IT GETS WORSE, MOVE THE CLIP UP WHICH WILL REDUCE THE GASOLINE.

Posted: Sat May 06, 2006 1:13 pm
by TrevorLHC
mine did that then i put a piece of tape around the whole airbox to seal it really good then it ran like it was brand new!!

Posted: Sun May 07, 2006 10:30 am
by Farfignugin
thank you denmanshaffer, i will try that, will that also cause it to back-fire at full throttle?

Posted: Sun May 07, 2006 5:15 pm
by bfizzle
A tale tale sign of running too lean is backfiring.

Posted: Sun May 07, 2006 7:36 pm
by Farfignugin
ok, well, with all that aside, found out something new, my bystarter wasn't in right so I got a new o-ring and fixed that, now it idles great! But... on the other hand, now it seems to die out (maybe either too much fuel, or vaccume leak my dad says) after warming up for a while (runs fine cold). Any ideas?

Posted: Sun May 07, 2006 8:00 pm
by noiseguy
I'd guess a vacuum leak too. Symptoms definately sound like you're running lean.

Posted: Sun May 07, 2006 9:23 pm
by Farfignugin
where would the most common vaccum leaks be?

Posted: Mon May 08, 2006 9:29 am
by noiseguy
Most common? Installing the plastic thermal decoupler backwards, with the o-rings touching each other. This is the brown plastic bit b/t the carb and intake manifold.

There are 3 ways to install it wrong, and 1 right. The touching rings one is least obvious; I've done this before. Scoot ran like crap.

Posted: Mon May 08, 2006 3:36 pm
by Farfignugin
wait u lost me on the thermal part, but anyhoo, its the thing that separates the carb & intake right?

Posted: Mon May 08, 2006 6:30 pm
by MySpree
yea thats the part.

Posted: Tue May 09, 2006 12:10 am
by bfizzle
noiseguy wrote:There are 3 ways to install it wrong, and 1 right. The touching rings one is least obvious; I've done this before. Scoot ran like crap.
So the rings are supposed to be touching?!?