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Scooters - 50cc => Super 8 => Topic started by: bahiano on December 06, 2011, 08:48:47 AM

Title: Idles fine then dies when accelerating...
Post by: bahiano on December 06, 2011, 08:48:47 AM
Dear all,

just put a 72cc kit on my 4 Stroke Super 8. I changed the main jet to a 88 and took out the Air Box constriction.
It ran perfectly for about one hour test drive and then all of a sudden while driving it died.
I started again and it runs fine, but when i accelerate just a bit it dies again.
Spark plug look quite black.
My scoot is quite new and run about 2000 KM
What i checked so far:
Carb complete, including all membranes
Valve clearance checked
Zylinder Head Gasket
Intake Manifold no leackage
Compression
Vacuum tube for leackage
Spark looks ok (blue)

Plans:
CDI ordered for testing
New High Tension coil for testing
New Carb ordered for testing

If that also fails, i am truly out of ideas, maybe anyone had the same problem and the solution
is something completely different...

Thanks and regards from germany,

Markus





Title: Re: Idles fine then dies when accelerating...
Post by: spidrgr on December 06, 2011, 07:55:02 PM
Dark plug: too cold. Usually, too rich a mixture for the plug temperature range. Go the easy way first and try a warmer plug. Otherwise, go down on the jet size. You say you have a 88. Try a 85 or even a 82.
Title: Re: Idles fine then dies when accelerating...
Post by: bahiano on December 07, 2011, 06:00:26 AM
Thanks, today also my new Carb arrived, i will test it later...

Cheers Markus
Title: Re: Idles fine then dies when accelerating...
Post by: bahiano on December 09, 2011, 07:01:25 AM
Ok folks, changed the complete Carb and it runs smoothly... cleaning the old carb did not help a  lot in this case...
Now finally i will enjoy my 72cc  ;D