Re: hello,lisa here
It looks like you are going to need a new motor..
re the 18mm carb - you will be able to use it on the new motor with the following provisos..
1. run the engine in on the standard carb - details on how to do that can be found on the forum.
2. when you do fit up the new carb/intake use gasket sealant to make sure there are no airleaks (air leak means lean condition)
3. You will have to run the mikuni carb richer so you might need to change jets to make it work. Richer means a bigger jet - leaner is vice versa. There may also be a adjustable clip on the carb to adjust mixture as well as there is on the CIF engines. DO NOT run the engine at speeds where it starts to sound rough - if it does that at high end then you need to go richer on mixture.
To get the best performance out of the motor (after it is run in) get hold of a tuned pipe for your size engine - combined with the Mikuni carb that will give you the best performance.
hope that helped.
"....Look, no pedals... *thud*..." The mating call of the motorized-biker.
"RetroEagle" - 32cc Two-Stroke, Piped. 35mph on #13 gear. Reversed stem with springer fork.