when you rebuild your motor it's a good idea, i just ride mine around car park a few times, shut it off let it cool down, do that about five times to let rings seat, then go to the track and race, but thats with race tolorance piston to bore.

i'm thinking of riding again  so will have to change my set up, but will still heat cycle at the start.

and like it was stated, change your oil early first time to get all the machine metal out the oil, but my mate Cow that builds my motors spends hours cleaning the barrels, some don't spend that much time on that job.

cheers