My 50cc scooter engine will only work whilst I'm revving wen I stop revving it completely cuts out, I was told it might be to do with a screw that needs tightening,can I do this myself or do I need a mechanic?? Please help asap thank you

Sam, September 2011

You don't say what type of scooter,or if you were using it daily until you got this problem.If you haven't touched any screws on the carb before the fault don't touch them now,they don't move by themselves.There are other things to look at first,pilot jet or slow running jet as they are called looks like a favourite,dirty carb,don't fiddle with the screws unless you have done work,they are factory set.

Rich, September 2011

it could either be the mixture adjusting screw or the tickover adjustment screw and neither of them tighten up by the way! but start with the tickover adjustment first as thats what it sounds like, you havnt said the model scooter so will assume you can see or remove a cover to see the carb, on one side of the carb should be a protruding screw- some have a spring behind it to stop it moving-it'll be central vertically to the carb body and just up from the float bowl joint, start engine and screw it inwards until the engine speed picks up.

Ted, September 2011