The plans changed significantly on this build, so skip down to here
for the Bike-E build I ultimately ended up doing.
So after several years of owning, and loving, using my Stealth Fighter as a commuter, I've decided to get sensible and build up a more appropriate bike specifically for the purpose of commuting to/from work each day.
I'm not tossing the Stealth of course, just relegating it to weekend usage, and the occasional commuting via an off-road route.
The new bike will need to be reliable, and cheap to build, since I'm pouring most of my time and money into upgrading the Fighter continually. I'm aiming for a minimum of 45kmh top speed and don't mind helping the motor get there if it lacks torque. I want to be able to use Regen, so a DD hub motor is the preference.
I've already got batteries.
These were in my Fighter, but they've started to puff a little, so I'm not comfortable bashing them around off-road any longer. They should make for a nice commuter pack where they won't need to deliver anywhere near the amps my Fighter was drawing.
I've also already got a beefed up 6 FET (4110) controller curtsey of Jay (Hyena) and a throttle ready to go.
I've got two bikes to choose from for the conversion. Both were given to me for free from a friend who did many many miles on them over the years. He even rode the Mountain bike from Sydney to Canberra (300km) in one day back in the 90's!
The first option for the conversion (and my preference at this stage) is the road bike.
The second option is the mountain bike.
Both bikes have 135mm rear drop out's. The road bike has 700c wheels and the mountain bike 26".
The road bike rides a lot better and more comfortably on the road (and even light off-road), but it is heavy for what it is. It's weight mainly comes from it's tubular steel frame, which I guess is good for e-bike building since it should also mean it's stronger.
The mountain bike has a strange feel to it due to the extended head stem and geometry. Once you get used to it, it is quite a capable off-road and I've ridden it on some pretty gnarly rough stuff successfully. It's lack of suspension simply means a different riding style must be used. After decades of only riding mountain bikes with suspension, I'd forgotten how responsive a mountain bike with no suspension can feel off-road. You can really flick it around even though it's not the lightest thing in the world(still lighter than the road bike though).
Both bikes are also rim braked, which I will not be changing.
To me, either bike would make a good commuter conversion, however there are drawbacks to each.
The road bike's main disadvantage is the fact that it has 700c wheels. The increased strain on the motor and controller is a disadvantage, but one I'm happy to live with. The main problem is, if anything significant breaks on the bike, it won't be worth fixing and instead I will get another used bike to move the kit over to. In that case I would prefer to be able to buy a used mountain bike, but the motor in a 700c wheel build would not work with that. I've also got some thicker tires to use on the road bike, that should make the ride more comfortable.
The mountain bike has fatter tires for comfort, and being 26", if anything significant breaks it's very easy to buy a cheap used mountain bike to move the kit over to. The only issue with it is the bike is not as good quality as the road bike and the ride is a little strange. The brakes, grips, gears, cranks, and bottom bracket are also much more worn, and lower quality compared to the road bike.
All that's left to buy for the conversion is the motor/wheel and a bag for the batteries. In either case I will be getting a triangle frame bag.
http://em3ev.com/store/index.php?route= ... uct_id=125
And for the motor, I will most likely go with the 500W DD hub from Paul @ em3ev.
http://em3ev.com/store/index.php?route= ... uct_id=112
The motor wind is slightly higher than I would like at 268rpm loaded (36V), but it still seems like a workable option for 72V LiPo (am I wrong?). I could also potentially change the battery setup from 18S to 12S if it's too fast or inefficient.
Anyway, what do others think about which bike I should use for the conversion? Is there another option I haven't considered with these bikes?