First kit ordered actually had a bad wire inside motor. Customer service stepped right up. Installed kit. No wire diagram but very easy install. Just pay attention to how you take apart factory wiring. Everything is labeled. I just cut off original plugs and installed to new kit after cutting of unneeded plugs and used heat shrunk butt connectors. Studied up on YouTube videos. Easy install. So far working exactly as expected and posted.Update. With 9 and 11 tooth sprocket I can get up to 22.8. With 13 got up to 24.5. Just order 14 tooth sprocket. Not to bad for 220lbs. I even have my 4 yr daughter sit with me. Another 35lbs. I ride it to my local elementary school and can ride for a solid hr in some mild terrain. For price and ease of install cannot beat it. Ordered another kit to install on my sons go cart. Stay tuned.