Hi Neal,
I've fitted them to my MC18 F3 engine.
I haven't got any dyno comparisons, only seat of my bum!
I can post up the graph from when Steve dyno'ed the original complete MC18 F3 set-up. Max power was 67BHP.
Anyway, the RS top end compares very well to the '18 F3 set-up.
On the track, Dan Williams' well developed MC21 F3, according to him, was out dragged from the corners by my bike. Considering at best, I'm probably two stone heavier than him, I was quite impressed. He reckoned his bike had the legs on mine on top end though.
He did beat me quite easily, rather a lot last year, although I think riding ability also comes into play.
Another excuse is I was using standard NSR size brake disks, which probably due to my lardy arse, meant it was the first time I've ever experienced running out of brakes on the track. Excuses over, Dan was better than I was!
Personally, I just like the proper race bike set-up of the RS top end.
The cylinder head o-rings make stripping,inspection and rebuilding easier/faster.
The locating dowels ensure the head goes back in the same position every time.
The power-valves are better.
The only thing I want to get made is some exhaust stubs that match the port profile, like the Tyga/Dogfight special manifolds.
I found myself changing up at around 11500/12000rpm, although I could over-rev to 13000 if needed.
My road bike 300 engine didn't rev like the 250 engine.
Not much point reving past 11500. Hit a brick wall at 12000. Plenty of wheelie grunt though!
I've done a few other different things to my bike.
I can pm you some pic's of the airbox, subframe and front forks that I'm building up if you like.
I have posted pic's in the members build area of all this stuff.
PM me if you want some more advice.
Cheers,
Roy.