now having replaced my plugs and points, the cart runs great...except when the lights are on or at night.
The twitch in the tacho is back at night with thte lights on.
The idles drops to 700 rpm from 900 rpm, and upoon gradual acceleration, the car vibrates and stumbles abit. It feels like the hand brakes is on almost, and the car runs rich, pumping out some smoke.
The handbrake is definately not engaged, and i am not loosing oil or anything.
I think my ignition system is breaking down when i turn the headlights on, or there is excessive electrical draw.
The only electrics the car has are all the stock lihgts, the demister (not hooked up at present) and a spot light on the back (also not turned on).
Is it time for a new alternator, or is there another explanation.
I dont think its is a vaccume leak as it seems only to occur at night and with thte lights on.
Soory about the long post.

I would get my alternator checked out. It sounds like it is only doing it under high electrical load, so the alternator may have a short in it or something. If you take it off and take it to an auto electrician they'll test it for you.