Why wont by gilera runner sp 50 start??!?

well mate the cdi and the coil are all in one unit so you wont have to buy seperate items.
it will be one of the following that is the problem
1,the primary ignition coil or pulser coil is faulty on your new engine(providing your not using your old ones)?
2,the cdi coil is faulty(not likeley as it was ok before)
3,the green wire that goes from the cdi /coil up into the loom is touching earth somewhere?it goes all the way to the ignition switch.the cdi has 2 green wires going into it one goes to the stator in the engine the other is the one you need to check cut it and rejoin it if necessary to see if its the problem.
4,the part on the back of the switch is faulty (unplug it and see if it sparks)
5,the ht cap is breaking down ,unscrew it and hold the wire about 1mm from a metal part of the engine or frame and see if it sparks when turned over.
6,the wiring from the engine isnt connected to the cdi/coil properly.
there is nothing else to it.
if its none of the above aprt from the stator coils then you will need to change them on the new engine for the old ones stator .i would say out of all these its liley to be the stator as its the only thing you have changed
so check the ht cap first then unplug the wire on the back of the ignition switch then cut the green wire from the cdi that goes up into the loom (not to the stator)then try another cdi/coil then the old stator assembly.you will solve it doing it this way i promise.

adam bike doctor
June 2010

I would recommend you try a new coil and if that dont solve the problem then maybe a new cdi is the way to go.

Martin
June 2010