Re: China Motors....
(Quote: "But i do plan on moding it for longevity not for speed.")
If this is your intent for the build,
1.just do a simple deburring of the ports, (don't raise or lower either exhaust or intake port)
2. get a piece of wet dry 320 grit sandpaper and tape it down flat on a piece of plate glass, and true up the surface of the cylinder deck and also the head sealing surface if you plan to use the kit supplied head.
3. as I said before I recommend getting some regular or flange type 8mm nuts to fasten head down instead of the acorn nuts that usually come on engine.
4. install a better upper bearing when you go back together with it and be sure to oil bearing and piston pin good when yuo install them.
5. use loctite BLUE on all nuts and fasteners and get them good and snug but don't get to rough with them since most are small 6mm studs and bolts and they are fairly soft steel.
6. The rear mount of the engine to frame is the most critical, make sure it sits flat on the frame, do NOT use rubber or anything else between engine and frame, tighten stud nuts good with loctite on threads but dont over tighten or they will fail in a short time, I actually like to double nut the rear studs by adding and extra nut on each side and then tightening the outter nut down very tight against the inner nut while holding the inner nut secure with another 10mm wrench, just extra security since the rear studs will normally be the first to give a problem if theye aren't done correctly.
7. Be sure to get sprocket straight and true on wheel.
8. Lastly, make sure to get he carb tuned properly for the mix you plan to run, run whatever oil and mix you feel confident with, I will not say more than this since this oil and ratio topic always opens a big can of worms on here...LOL!
best wishes on the build.
I dont always ride WOT, but when I do..I do my best to keep the rubber side down..Ride safely my friends!