how do you figure it runs better without the heat from a heat gun? all the use of a heat gun does is allows the sleeve to expand before the initial start of the motor allowing for less stress on the CONROD. until i have about 3+ gallons on my ninja i will continue to use the heat gun. it is also smart to not start tuning an engine until the motor and chassis are completely up to temp so again here using a heat gun allows you to get to this process faster.
just my .02