Aircooled Monoshocks

I've noticed that in the ACU Classic trials that they are using the new Scorpa air-cooled 125s and this lead me to thinking. I noticed that the bore on the Montesa RT4 and XR250 are the same. Therefore, could I use an air-cooled RT4 with an XR250 head in the ACU classic series? The engineering isn't a problem and I haven

I think this bike looks awesome . Mecatecno were such a small company but somehow out of enthusiasm rather than business sense they made their own engine entirely. The piston was shared from a Bultaco 325 and the cases are all magnesium making them very light and fragile. Unfortunately the economic crisis is Spain in the lates 80's early 90's proved too much for them. RIP

This is when bikes were bikes.... and we fell off more A good shot of Eddy Lejuene on his Merlin DG 350 FIUS for 1988 - (where's his glasses?)