recommend a good CDI/sparkplug?

[Giovanni Q.]

hello all. i was wondering if anyone can recommend a good cdi and spark plug combo to use. when i first built the bike i got a supercharged cdi, this guy here, https://www.amazon.com/Super-Charge...ld=1&keywords=80cc+cdi&qid=1594754104&sr=8-33
i think it ran rite for like a day. had to take it off and go with the stock casue the plug broke and i had to order another one. the bke ran so much better with the stock. when i got the new plug cap i put the super charged back on and it ran aweful. so now im back to the stock cdi. my current spark plug is a nkg 4085. i rocking an 80cc costway (i know its not the best but it was my first build. i know what im getting next time) iv got to beleave there something out there better then the stock cdi and the super chanrge crappy one i tried. i dont want to buy a chrap 10 cdi but i also dont want to buy one thats expensive just cause "it must be good" any help with recommendations would be greatly appreciated

 

[GreasyChris]

Ngk b6hs or b7hs is the spark plug of choice. And I have tried many different cdi's and find that the stock cdi is one of the better ones.

 

[Giovanni Q.]

Aftermarket CDI's retard timing quite wildly too depending on the schematic they used. AKA it takes 10-20degrees slowly after mid range.
Most cranks now will be keyed static 25-20* degrees depending on factory cut and magnet key position used. Leaving plenty of room for the the stock box to advance 9 degrees without having bad knock / vibrations of the older engines.

Best bet is to run stock box or add 5-10 degrees of timing to the rotor with an offset key in conjunction to the aftermarket cdi. You can set it carefully without a woodruff key but you need a degree wheel and it all setup accurately. (This can be a pain)

I do have to say the gain is very little. Engine's today aren't cut with bad timings as the older ones. As is all the old benefits of this improvement exist with the stock box. The only exception is if you run a proper expansion chamber. That is a whole new bit of potato's.

expansion chamber is next on my list. recommend any good ones? when i bought my kit i ordered a flyingpig muffler but aftet hours of heating nad bending i still couldnt get the damn thing to fit... so im looking at one of the simple banana style expansion chambers. any recommendations? and so i should just buy a 10 doller replacement cdi is what your saying? i do hours and hours of reserch and still dont know whats best to get.... so i figured ask people that know what there doings opinions