My aprillia rs50 keeps cutting out all cdi unit mag and. reg all replaced.restarts straight away.sometimes you have to bump start.thanks

Jets in the carb may need blowing out,do not try to put anything in them,just use compressed air and solvent,sometimes dirt collects in the float bowl and when the carb is removed for cleaning it finds its way into the jets,sounds like the idle jet is blocked

The biggest villain on a PX is the wire sheathing from the stator to the outside of the engine, it gets chafed off and causes an earth out.

Also check the frame to engine earth, CDI and coil earth's as they are susceptible to corrosion which breaks the connection.

CDi/Coil and regulator units do fail when they get hot and can exhibit the symptoms before they shut down, when they cool down they work again so maybe get a load test done on those or replace with a borrowed known good unit.

Soft and hard seizing can be caused by damaged cylinder, piston rings, cracked crown, cracked piston, also a failing exhaust will cause merry hell with running.

maybe a loose wire.check all wires

check the basics,
is the a spark at the sparkplug?
is fuel getting to the engine?
is the engine compression ?

good luck

Tty a temperature sender unit.

when you look at the cdi you should se a recess in the corner just a small little recess , enough for a small drill bit to fit , drill the small nipple located in the recess
and i am no expert , just persistent at researching the net

new battery?

i found the answer on another web site 125 racing .com

sensor ,go to ford garage