Ducar 200 dies under full throttle, advice needed please

[fxpro]

my 200cc ducar has just had a new mikuni carby fitted ,new spark plug and new fuel lines and filter also I drained the fuel and put fresh fuel in it .. the bike starts well but anything above 2/3rds throttle it completely runs out of puff and crackles and farts etc does anybody have any ideas what the problem could be as im at a loss ,is it possible that the coil or cdi be braking up? or is there anything special I have to do to a brand new carby when its installed ,john

 

[jev]

The carby needs to adjusted to suit the engine.
You need to remove the slide and adjust the height of the needle.

 

[my67xr]

Is your foam air filter oiled ?
if not it will be too lean.

the mixture screw will need to be adjusted to suit the engine/ignition/exhaust combination you are running.
warm up the bike, and turn in the idle speed screw about 1/2 to 3/4 of a tun to raise the idle speed a little.
then adjust the idle mixture screw in or out, so that the engine runs at it smoothest/fastest point.
eg if you turn it out 1/4 and the speed increases, you are going the right way.
adjust the mixture screw 1/4 turn at a time, and let it settle as it runs for 5-10 seconds,
when you get it close you can adjust it 1/8 turn.
once you are happy with it idling fats and smooth, drop the idle speed back down to normal again.


the clip on the needle shouldn't really need to be moved from the centre notch,
at least not until you have all the other circuits runny correctly.

 

[fxpro]

thanks for your responses can the foam filter be oiled with k&n filter oil as ive got some of that from my car or do I need some other oil and ill give the tuning a crack and see how it goes, im determined to get the ****ter running right .

 

[my67xr]

yeah the K&N oil is just as good as any