Motorcycle Repair: 1967 honda ct90, honda ct90 motorcycle, motorcycle work

Question
hello there i have a 1967 honda ct90 motorcycle
rain fine till i got a broken ring had head profsinaly rebuilt by machine shop that spechializes in motorcycle work reasambled bike but know cant get motor to run used to start first kick wont start as far as i can tell it is getting gas to the carburator and good spark at the plug what do yoy thinck could be wrong please let me know any info appreachiated

Answer
Brian... When motors come apart, someone better know how to put them back together again, properly. First, the cam timing must be done correctly. Check the valve clearances (.002") COLD on the compression stroke. Then, check the compression.. Should be around 150-175 psi with open throttle. If you have those ingredients, then you can go to the ignition. First, the battery has to be fully charged! Then, be sure that the points are opening on the F mark alignment on the COMPRESSION stroke. If not, then the point cam may be reversed on the point advancer assy.
Point gap should be about .014" at the highest part of the point cam, then move the point plate until they just open at the F mark. Check for a good spark at the plug, using a new one and a good spark plug cap that is around 5k ohms or less.
Finally, check the carburetor for proper float level. 21.5mm for a CT90 and 23.5 on the K1, in case you are off on the year model. Be sure the fuel is flowing and that the idle jet is clear and clean.

Bill Silver