Motorcycle Repair: no spark, piston crown, point gap

Question
I HAVE AN OLD CAN-AM 175 BOMADEAR ENGINE WE CAN GET INTERMITANT OR NO SPARK HAVE TRIED CLEANING FLYWHEEL NEW SPARK PLUG CHECKED COIL GROUND THE BIKE RAN  A COUPLE OF YEARS AGO BEFOR IT WAS PARKED AND ABANDONED. WHERE DO I START


Answer
Mike,
  Partial, inconsistant spark problems more times than not are caused by malfunctioning points.  I'm not to familiar with that model but I am assuming it uses a CDI/point ignition system rather than a modern electronic system.  Here is some info I've given others about point maintenance:

There are 4 things that can cause a ignition problem here.

1) The contact surfaces are corroded and or charred causing poor contact

2) The gap is incorrect

3) The timing is incorrect

4) The condensor is bad

If the point set looks bad, replace it along with a new condensor. If the condensor is bad it will make a new, properly adjusted set of points not work. Be sure to set the point gap to the proper gap and turn the whole point assembly until the timing is correct. Each manufacturer reccomends a diff. way to set timing, either by distace of piston crown to TDC or angle of crankshaft. My advice would be to get a hold of good manual for that engine and follow instructions on point set up.

Hope this helps,
Mike