To get it to slide on properly you have to shave down the sides a bit to clear the cases. Transfer area is not big enough for the metrakit, but whatever. I'm running one with a euro kit/19phbg/tecno bullet that is the fastest accelerating v1 I have ever ridden. Power wheelies like wow and a 52 mph top speed, could add gearing and get into the 60s for sure. Would like to try a puch polini or maybe a treats kit. V1 are the best.