I had an Ossa motor in a slider. It was a Stilletto 230cc motor and went pretty good. I bought it from Sam Skilling
in Vic. Then we got hold of some roadrace specs from a bloke in Melb. east/suburbs,can't remember his name.
WOW! What a differance. Reshaped the ports,raised the compression, single ring piston with modified skirt, all new pipe dimensions, high octane fuel etc. etc. Very quick with a useable powerband. GREAT motor. Trouble is,...have access to 4 motors but I don't have the templates and specs anymore. My Dad passed away a couple of years ago and my brother and I have searched everywhere for them to no avail. Hint, hint,....another Ossa flattracker would be nice. My brother reckons he would be pretty keen to put one in a good flattrack frame,.......
regards Mark