Anyone try to convert one of these yet? I was thinking about doing a large conversion (up to 150cc) just wondering what the experience of others was on this.

I have converted a single 216cc Solo ultralight engine, a Stihl 090 chainsaw, a Whizzer motorbike, a West Bend GoKart single, a few 289cc twin cylinder drone engines, all worked well...
The big singles don't shake as bad as you would think, and start really easily...
They're HEAVY