How long have you owned the bike ?
Whats the mileage ?
Serviced regular ?
Always done it / Just started / Gradually got worse over time ???
Does it back fire at all either on cranking or running ?
There are a number of things that can cause your grief..
Ignition timing out. (CDI faulty)
Water getting into the combustion chamber.
Mixtures incorrect.
Air leaking into the combustion chamber.
Carb internals loose/siezed/worn.
Valve clearances.
Faulty battery. (Sounds daft but you'd be supprised what problems they can give you)
Whats the mileage ?
Serviced regular ?
Always done it / Just started / Gradually got worse over time ???
Does it back fire at all either on cranking or running ?
There are a number of things that can cause your grief..
Ignition timing out. (CDI faulty)
Water getting into the combustion chamber.
Mixtures incorrect.
Air leaking into the combustion chamber.
Carb internals loose/siezed/worn.
Valve clearances.
Faulty battery. (Sounds daft but you'd be supprised what problems they can give you)