Rohan wrote:C'mon, thats the famous JAP 8/80 Race Engine.
Can still buy them new.
Cameron Racing Engines, Greg Summerton and the late Bob Jolley could all supply them.
I watched Bob Jolley race the 880 JAP/featherbed at Winton some years ago. It was OK, however seemed to pull harder than it needed to, with not enough top end. The Norvins were better at the time, however none of them would be a pleasant ride. It makes a big difference how far forward you can get the weight with a featherbed framed bike. The bikes in the photos look great, and in theory should be good to ride. However the practice sometimes doesn't reflect the theory. It is never as simple as just fitting a motor into a frame.
I can remember a time when I found it impossible to get a respectable lap time with my short stroke Triton. I moved the motor forward until the front engine mounts touched, and the bike stopped feeling vague in corners. That restored a bit of confidence. I look at some of those photos and recognize the potential for getting a hard time. I crashed a lot when I was a kid.