"The now defunkt YS .53 FS would outrev all sport two-stroke 60 engines and even some piped ones. All on 60 size 12x6, 11x8/7 and 13x6. "

I have both YS53s and 63s and they are fabulous, but out rev, out turn, out power my good 60 2 strokes. I doubt it. In a direct comparison my OS 60 FSR on a 13/6apc prop would only do as well as the YS63 if I stuffed the OS60FSR exhaust with rags so it wouldn't shriek at me.

You must have some sick 2 strokes. Just kidding

I agree the The YS 53/63 and Saito 72 are wonderful user friendly engines that certainly are competitive with 60 2 strokes in many if not most applications AND WILL FIT where a 40 2 stroke goes. And they sound so cool.

Geez I guess I did instigate something.

Denis