Got my NB48 built and went to break in the engine saturday. Not a good experience. All my own fault. 90% of my problem was that I didn't have the wheel on the starter box properly lined up with flywheel. It would touch the flywheel but was rubbing on the chassis too because it was to close to the outer edge of the chassis. I thought the motor was just tight. Anyway extra strain on the starter box quickly burned up some wiring inside that I had to repair. Fixed everything then gave further attention to my problems and figured out the problem with the alignment. Made the necessary adjustments and gave it another go yesterday and everything went very smooth. Got my engine broken in and ready for a race tune,.... and plenty of crashing.