I prefer the stock mount for the Hatori pipes too. I ran my CDI in the driveway tonight for the first time and plan to fly tomorrow. For this first run I used a nicad pack I grabbed from the bench thinking it was charged enough. The motor started easily and ran well at third throttle but did not want to advance into the upper throttle band. I started thinking that this motor was tight or something. After the initial run, the motor did not want to start again and actually "thumped" badly. This is so anti-the experience other people are sharing that I thought for sure something was wrong. I switched out the battery for a fresh one, and the motor ran PERFECT.

So, the moral of the story, always make sure you have a fully charged battery on the ignition. If the motor acts a little funny, it could be a low battery. Just something else to add to the trouble-shooting bag of tricks. I have the Mejzlick 18x10 on it now for break-in, and the APC 19x11 to try later.
Thanks,
Jim