The 48 volt 2000 watt motor, controller, and handlebar throttle came fast by FedEx. I installed the unit on a 3 wheel trike. The bike had a place I thought might accommodate the motor. The project took several days . I had to make a plate and secure it with some bolts to the frame. Drilled holes in plate . The Double D sprocket that comes from china will need replaced with a #25 or #35 by 10 tooth double D sprocket so you can match it to another Sprocket on the axel of the bike. That way you use a #25 or #35 chain to run your trike. It takes some engineering, time and you would save almost $2000. As electric trikes are expensive. I purchased a 48 volt 14Ah lithium battery from eBay delivered for less than $200.00 . I was a grain farmer in the south, so working with things like this was not to difficult. Many trips to hardware store for bolts and nuts. I purchased a 3 speed switch from Amazon . I do not have a speedometer but I am sure it goes over 25 mph . Powerful motor. You have to ease into the throttle as the torque is powerful. I purchased a controller cover/box from Amazon to protect the controller. Takes a large one. The box can be secured to the bike with clamps, like what you would use on a hose, but much larger. It took a lot of time but at 77 years old , I have enjoyed the project. In my case a 70 tooth sprocket was needed, but there was no room so I placed a Jack shaft between the motor and the axle. This requires 2 chains and sprockets. It can be done. Good luck. God Bless.
Dennis 
