Just trying to add some activity to the forum....
My Nano is an earlier version with the slipping belt pre-rotate pump drive.
I recently upgraded to the HD clutch option, and after some teething troubles setting it up have got it sorted and working well.
Pre-rotate is much more positive with no slipping as the rotor load increases above about 160-170rrpm.
I have posted a video of my flight yesterday on youtube- nothing spectacular, just a local round the patch- no dramas, just an enjoyable cruise.
Link here- https://www.youtube.com/watch?v=KPgixOr-Rg8
I had earlier on struck some issues with the exhaust/muffler system due to engine vibration at startup and idle.
I spent some time looking at the issue, and decided it would help to uncouple the inertial mass of the muffler from the engine to relieve any stress on the exhaust flange and joints.
I added flexible joints into the exhaust tube between the engine and mufflers, and things look and feel a lot smoother at startup/idle.
Pic below.
@Mike Gonce
Got your email thanks.
The best solution for me was fitting the flexi joint in the exhaust.
I took the pipes to a muffler shop and they cut and welded them for me.
Make sure the overall length remains the same- for exhaust tuning and fit to the silencer.
I had to move the EGT sensor boss slightly further from the exhaust port to clear the flexi joint.
I have been running with this setup for about 50 hours now and am happy it.
Isolating the silencer mass from the motor gives me a smooth idle down to below 1500, and it removes any misalignment stress from the pipe/flange joint.