Tuned Ported High Performance Motorized Bicycle 66cc

Never made a video of this with the new mods so here it is, still same motor from last video but now has 2000km on it but a new clutch, piston, rings and cylinder was installed for top performance. Sounds like a dirt bike :D this is also aka 80cc engine (really its 66cc). I have ported the cylinder ports as wide as I can and semi polished them, I also raised the exhaust port a few mm and now it has only top end power. The banana pipe (tuned pipe) is modified to be a true expansion pipe. Piston is also lightened by removing extra material inside the piston skirt and piston port ramps. Air filter from one of my rc trucks and last is NGK cold spark plug (supposed to be in summer). This thing tops out at 60km/h but once I put a smaller sprocket, it can easily reach 80-90km/h and maby kill me at the same time. Still need a custom cdi, increase compression ratio and custom walbro carb or reed setup. Ultimate guide for high performance mods http://www.dragonfly75.com/motorbike/