Hey man,
Glad you're liking the scoot!
Batman, the Prima cylinder is very lowly timed. If you just bolt on a stock Prima cylinder in place of your OEM bore, you would likely not notice any difference in performance. This is because the Prima, Charmo, etc cylinders for this bike are like re-bores, and because of the angle that that the port enters the cylinder, re-boring the cylinder lowers the ports. Bigger cylinder is good, but lower timings make the difference in performance hard to notice. The cylinder on Wordslinger's bike has had the exhaust cleaned up a good bit, and a re-cut head. The compression ratio is high (Higher than safe, some would say but it's been doing very well, and runs good). That said, this Prima cylinder runs pretty good. I chose to keep the stock carb, filter, and pipe because the Prima cylinder's performance is so close to stock. Normally I would use a Dellorto carburetor with a cylinder upgrade.
It's late. I'mg oing to bed, and I'll catch you guys later. Congrats on the bike Wordslinger! I'll let you know when I can come over for a ride.
~Josh