> Dr No Fun Wrote:
> -------------------------------------------------------
> Get yourself a piece of sheet metal about 3 mm thick put it under the
> cylinder with a gasket on each side.
> After completing the above you will need to trim off the top of the
> cylinder so you have a squash of .8 mm 1.1mm at the outer edge of the
> piston.
this whole post is good stuff, i dunno if its minarelli specific or what... but this part is really tough for most people in home shops, the v1 has that stepped sealing area on the head that makes it really tough to cut down, especially 3 mm.
my general 5 star had an evracing pipe (basically a tecno bullet), a 15mm bing, and very very mild porting, went 40 + with stock gearing and trucked, probably could have been 45 with taller gears. You don't have to mess with lathes and spacers and all that, but the specs (165 exhaust/ 135 intake) are kinda the max for stock cylinders without loosing a bunch of low end.
I don't really port transfers on stock cylinders much, that might be the difference between 45 and 50 mph bikes, it just seems like a lot more work than its worth unless you just want to be able to say you did it. All the single speed 50/50 bikes i've ridden have been pretty doggy off the line. I like my 45 mph stockers that rip hard off the line.
Believe it or not, the guys that designed these did actually know what they were doing, they were just targeting reliability, torque, and a 30 mph max speed. It takes surprisingly little porting to wake them up.