gilera runner 50 boggs down weird

Basically my gilera broke down and i couldnt get it runnin now ive replaced the battery ignition coil sparkplug and stator plate it runs but its slow for instance if im going up hill it will only go to 30 if i try and rev it more it will slow down fast and cut out also the headlight light on the dashboard sometimes goes off but my headlights are still on so i think its an electrical problem anyone got any ideas thanks!

 

What does the bike have on it? Give us some info

 

well basically ive put back on the standard exhaust ive got new 4.7g rollers it starts and idles fine but asoon as i left for college this morning i couldnt get more than 15mph or it would just die down also i went to touch the sparkplug cap when the engine was running and i got a big shock and i heard a clicking noise maybe the sparks jumping?

 

Sounds like bad ignition if your getting electric shocks, replace the HT lead, plug and cap, and maybe a new cdi unit, but its possible the engine is bogging down due to an air leak. Have you checked the manifold and airbox?

 

i replaced the ht lead the plug and the cap and then i couldnt get it started to i changed my stator plate now this has happend i dont understand the airbox has no air leaks etc also it starts and ticks over fine and i can revv it to full throttle on the stand but asoon as i get on the bike it just dies