The intake port on the cylinder is a week point on the V1 polinis. I would suggest opening it up from the 17mm to 19 or 20mm. Its very simple and can be completed with file. Look here to see what I always do with my V1 cylinders. I dont think the port is big enough for a mikuni, but a 19-21mm carb is a perfect setup for these guys. Back in the day when I switched from a 15 SHA to a 19 PHBG it was good for 7mph increase. Ed is selling those CDI's on ebay and I think they are a good option and ED is super great to work with!