Hi guys i need advice.

Iv recently purchased a 2012 peugeot kisbee 50cc 4t off a friend for next to nothing as it was in the way, the bike was a non runner but after a swift carb clean some fresh fuel and a squirt of quick start it fired and ran fine, the issue i have is that when i hold the throttle anywhere from 3 quarters to full it will rev up and then cut power for a second then power again then cut again and so on until i let go, (impossible to ride) it kinda sounds like a rev limiter but it definatly did not happen when my friend owned it and rode it for a year, so my thoughts lean towards an ignition/spark issue? But do not know where to start other than replacing the plug tomorrow when it arrives in the post, any advice/tips would be much appreciated!

 

Are you doing this on the stand or on the road whilst moving along?

 

It happens on the stand or riding, but like i said it has never done it before in the whole time my friend owned the bike so im pretty certain its not ment to do it

 

To see if its the restrictor, try taking it off,its a blue wire coming from the transmission, left side of the bike.
Sounds like spark plug is loose to me, or a lead anyway..

 

Tried with blue wire disconnected it dosent help, spark plugs tight and ht lead/caps fine, its litrally like holding the bike flat out and keep switching the key off and on, i cant get my head around it, i have bypassed the ignition barrel due to it having no key but i wouldnt of thought that would cause it???

 

When it cuts for that split second, do the lights go out or dim right down?

 

Im not sure as none of them are hooked up at the moment, if they were hooked up and as you say dimming what would be your suggestion?

 

Electrical connection, maybe loose earth under vibration. Hook up the lights and see what happens.

 

Oh yeah i have no doubt its somthing electrical but trying to find it is beginning to be a pain, it happens at the same rpm every time like its on a rev limiter

 

is it exactly the same issue when going up and downhill and on flats? Mine would do exactly the same on downhill runs as though the engine was revving too high so it cut out. Have you found a point where you can ride at a fixed rpm without this cutting out? If so then it kinda rules out loose wires and points towards the cdi / coil side of things. Have you got the right spark plug in? If you are running the wrong plug then it may cause issues. Try running voltage tests on the stator?