I've got a rs125 2001 at 4/5k is misfiring the power valve is kicking in until 9k then nothing I've all the power valve parts on bike can any body help me wot the cause could be

Peter, July 2015

3 things that cause that on an rs 125 with the rotax 122 and 123 engine are
the kill switch packing up
the ignition pick up coil next to the magneto packing up.
the catalytic converter coming loose in the exhaust and blocking the gas flow.
i am a bike mechanic and have been doing it for 22 years so im pretty clued up on this model.

adam bike doctor, October 2015

why do you think its the powervalve? could be a duff sparkplug, have you tried running it with a new plug, Try www.apriliaforum.com for setting powervalves.

wotshisface, August 2015