Kentucky-bum

Marco, The Instructable does a pretty good job of where to start and gives you a logical progression of what to do and when. But you do need to be somewhat of a 'back-yard' mechanic. You will need to figure out where to put the motor, fabricate the brackets for it all the while making sure you have some easy way to adjust for alignment and [maybe] chain stretch. In other words, you will need a bit of inventiveness to get that kit onto that frame. That being said, if your not mechanically inclined and not a dare devil, then you might go to your local high school and talk to the auto mechanic teacher (most high schools have a shop class that teaches auto mechanics). See if they will put it together for you! I know my local school would do it for me if I asked/needed, and they love that kind of stuff. But you may still have to lend a helping hand, as they may not be that familar with EVs. As for the throttle, just tie that PB-5 to the frame and run a cable from your throttle grip to it. That way it behaves just like a regular bike. That's what I did. You don't neet that fancy grip. Another point, you're gonna need more than those 2 batteries. You only have 24 of the 72 volts that you need. You'll need at least six 12-volt batteries. But get smaller ones! 115 amp/hr batteries are way too big (unless you are going to run a car!) You should be looking for 20 - 30 amp/hr RV batteries (look at wheelchair batteries). If you could use those 24 volts worth of batteries you'll go all day long on just those two, but you'll never get over 20 mph (and besides, I doubt your controller will run on 24 volts). I suspect that your controller is like most 72-volt controllers; it will run on anything from 72 to 120 volts (but not 24).

James, Having a 2 speed transmission would definitely help, but it won't double your mileage. Its biggest benefit would come in stop-n-go traffic. Normally it might give you 20% - 40% better range. Most single speed bikes (like mine) are optimized for 45 - 50 mph. Since electrics have so much more torque (than gas) at slow speeds, they don't need that lower gear to get started down the road. But they do use a lot more energy for the same equivalent horsepower before they get up top speed. This is where having a lower, 'start gear' would help. However, the actual cost of incorporating that 2-speed transmission and the additional weight may 'out weigh' the cost of a better battery pack though (which would give your 25 miles range), so you may have to do a little home work and [just maybe] a little experimenting to find the economic break-even point. But remember, the one advantage that an electric vehicle has over ICEs is that their range and performance can usually be upgraded over the life of the vehicle with a simple battery swap and a controller upgrade. Use that to your advantage when building your bike.