Scooterotica

just met a chap who`s rebuilding a 1963 lammy Li 150 what he found at the back of a garage (never that lucky)and he wants to keep it 6v now iv`e just got back from his place and what we are left with is ,its got a battery on,followed stickys book all wires in correct,but the spark is very faint,so we replaced the coil to a new one and still the same but when i take the wires of the coil and put the green wire to matal kick it over and the spark is good,new faulty coil ?? got another at my place or is there something iv`e mist

i take it that you put new points and condensor in it ? also the points have a coating on the contacts, also try making the plug gap smaller and if its the coil with 2 terminals try swapping the wires round and chect its all earthed up good

I run 6v battery lambrettas and have done for years, set up correctly they have always had acceptable lights and have been reliable , but in my experience the original ally coil, can be suspect, re-made ones can be just as bad, I always use a 6v points Vespa coil,original piaggio one if poss. same connections just need to fabricate a mounting bracket, I know its not original but its better.

well was down at his house last night again,good spark off green wire put coils on and put a screw in ht lead spark there but not as bright,then when i put plug cap on and plug in now there`s nowt coming of the plug,cud someone tell me what readings are we supposed to have coming out of the rectifier,he says its a new one but i thought id check it with the multimeter.
Ta Paul

forget the battery circuit it has nothing to do with the spark
you have an lt coil on the stator that provides power when the flywheel spins now as you know you are getting a good spark from this so thats probably ok
connect the coil up making sure there is no corrosion anywhere, especially where the ht lead goes leave the cap off and hold the ht lead with the open end next to the case and kick it over, the spark should jump the 3mm or so to the case and be blue, if the spark is good fat and blue then all is good there try with plug and cap if s**t then change both
if you dont get a good spark from the wires of the bare end of the ht lead to the case then try another ht coil, it doesnt have to come off a 6v machine as the lt coil kicks out a lot more than that but at low power, ive used mini ones and ford ones no problem however they are large so most ht coils will work
if that doesnt work then change points and condensor, which should have been the second thing you have done after new plug and cap
also take the green wire from the stator and connect directly to coil in effect bypassing cutout and connections on the rectifier
its just a proces of elimination so work from one end to the other changing a component at a time till you find the f@@ked item

Can't add much to what JS said apart from checking that the earth wire from the engine is in place and making a good contact at both ends.