Koupe
Welcome to this cool forum. After buying about 40 mab motors of all types and assembling several, which are all fun little machines, I would recomend a 4 stroke utillity engine. Getting very populer now. Lots of great 4 stroke builds on here -CCC, AGK, Cobrafreak and many more. Do some reading before you jump! It is confusing, too many options!! lol.
I will be starting my next diy build as soon as other projects are finished. At least a month away. It will be a Chrome Stretch Cruiser that I bought for $50 in 2009. Recently bought a 160cc 5 hp OHC Honda for $75, but it is too tall for the stock frame.
Recently bough a 140cc Honda clone with the angled cyclinder that runs perfectly for $50 of Craigs List.
Have it all planned in my head to be a no-weld build, have most of the parts in hand. No drilling of holes in the frame, Bicycle paint not damaged. Maybe only 8 hole`s drilled in the motor mount rails. Will be a very solid and dependable MAB. It is sorta like a "Cannonball2 " = he is a great builder. cheap and easy builds= one of his cool threads.
Was thinking primary and secondary belt drive with manual hand clutch with Jackshaft. Already have Workman HD front wheel with drum brake, will use it. Have a couple Heavy Duty Mongoose Electric bike rear wheel`s with left hand freewheel bearings/sprocket adapter`s so will go with secondary chain for now.
May go with the Gokart type CVT complete unit. My weight is about the same as yours.
My favorite current build is a diy Shifter with the 49cc Titan from dax. With the the derailer gears it is a real machine. Once you have cvt or gears you will prefer them.
The motor mount sketch will be changed, it will use two steel angle irons for the main mount rails. Even though the seat tube and down tube are very different diameters the width of my weld mounts are the same, no table saw mod needed. Had all the alum pieces cut for a few kits, but will go with the steel rails (paint them chrome to blend with the frame.
Am planing on removing the fan shroud and flywheel fins, installing a moded alum pulley for a rope starter to keep it as narrow as poss.
Sorry for the rant, but it may give you ideas
Ron