Hi i have just bought a 51 plate Aprilia RS125 that keeps dying on me. The bike starts ok and ticks over fine but needs so many revs to pull away but runs ok until i shut the throttle down and then it cuts out as if there is a fuel starvation issue. I leave it for a minute then it starts, i pull away and after a short time the same happens. Any ideas please as this is driving me nuts.

Thanks

Stew, November 2010

check for water in the fuel mate you will see it in the float bowl of the carb if it has but you need to undo the float bowl over a container to see it as the bolt that holds the float bowl on lets the fuel come out as soon as you undo it on these dellorto carbs.its running weak low down the rev range either way whether its a blocked pilot jet or water in the fuel.the tank cap well drain off pipes block up and the rain water runs straight into the tank everytime you open the cap up so make sure the pipes are clear or it will keep happening seen it plenty of times mate on these.

adam bike doctor(of milton keynes motorcycle centre), November 2010

you may be right,first of all i would check for clean and continuous fuel flow checking all pipes and filters for obstructions including inside petrol tank.While you're in the carb, check the jets by blowing a jet of air through them(from a foot pump) Make sure the float height is correct and the float bowl is free from debris.

Chris P.Duck, November 2010