[Lars!]

Well, let me first say that I want to convert a moped to electric.

Secondly, I'm only doing it for fun (and to show off to my friends, whom I've told for MONTHS that I will build an electric moped, but no one believes it ).

I'm not going to have any use for an electric moped, so my demands are very low..

Max speed 30-45 km/h
Range 20 km

And that's pretty much it. Of course it has to be able to go uphill etc. But you get the idea

Now here's my question; do you think this bike has ANY potential of being converted, given my needs (or rather lack of needs)



There's obviously not room for many components, but I don't need very much either. I'm thinking 48V motor, not sure about anything else. The reason I want this one, is because it's super cheap ($100) and super close to where I live.





Now, if that one turns out to be IMPOSSIBLE to convert, then here's another suggestion, which is also pretty close to my house, but about 4 times more expensive:



So what do you think guys? I'm aware that the second one will be a lot more easily converted to electric, but considering I'm only doing this project for fun, I also want it to be rather cheap.

So what do you think guys?

[Lexus]

Originally Posted by Lars!

Max speed 30-45 km/h
Range 20 km



So what do you think guys?

Me I would do the Trail Bike with this system (Cheap and Max speed 30-45 km/h Range 20 km)

(http://www.electricmotorsport.com/st...ors_etek-r.php)
EMC-R 48 Volt Motor Drive Kit
Includes: E-tek-R Motor, Alltrax AXE 4834, Magura Twist grip throttle, Contactor, Wire kit, Fuse and holder.
Price...........$980


But for FUN I would do this system (Double Price and Max Speed 96-112 km/h Range 40 km (if correct geared and Li-ion)

(http://www.electricmotorsport.com/st...ors_pmg132.php)
Perm PMG 132 72 Volt Motor Drive Kit
Includes: Perm PMG 132 Motor, Alltrax AXE 7245 (450Amp), Magura Twist grip throttle, Contactor, Wire kit, Fuse and holder.
Price...........$1795





Sorry I am a speed nut. I am using that Perm PMG 132 72 Volt Motor Drive Kit on a Mountain Bike Build called the Cheetah with 72volts of Li-ion Batterires.

[mxmtech]

I think the first one looks much easier (cheaper) to attain your goal. My own ebike has the speed and range that you are looking for, but not both at the same time. I am able to go 30 kmh but not uphill or into the wind. I am able to go 20 km but not at 30 kmh. The first one probably hasn't been abused like the second one but if it needs parts they might be more difficult to obtain. In order to get the speed you want you should probably have double the power motor than I have so that would be 900 watts for you. By far your biggest expense would be your batteries. To get the range you want you just have to buy enough batteries. You would probably need about 5 times the battery capacity that I have so that would be 48 volts 30 AH. At top speed (30 kmh) I can only go about 4 km without over depleting my battery pack (24 volt 12 AH). If you go with lead acid batteries they will weigh about 90 pounds so you might want to consider LiFePo4 (Lithium Iron Phospherous) at 48 pounds.
This looks suitable. Ebay item 290337362763 or this ebay item 130330176914.

[Lars!]

Now I've got another question..

Would a 1500 W motor be enough to push a bike weighing 200 kg (with a person sitting on it) at 45 km/h? Or would I have to go up in power?

[mxmtech]

I took my ebike and trailer across the weigh scales on wednesday. The combined weight was 175 kilograms. I had to peddle assist up a moderate hill to get there. My speed was probably a little less than 20 km up the hill but I made it.
Regarding pedal assist, I can't pedal fast enough to reach 45 km/h with my current gear ratio although I do have a larger front sprocket that I can install someday when I find the time to make an adapter plate.
By the way I find 30 km/h to be pretty scary at times, and is considerably faster than virtually every other bike on the road.
One bicyclist was as fast as I was but I think he was a competitor in a local bicycle hill climb contest because I haven't seen him since.