Hi Angus
I would not try that with a YS. I'm not sure if that little prop would even move that glider.
It's a 4M that weighs 6/7 Kg with no wheel under it, just sitting on it's belly. The Pletty had it up to about 2000 feet in 30 seconds or so.
It was a good laugh though.
3 is a crowd !!