Twin Outrunner build

I think it was six years ago that I first wanted to build an electric vehicle. At the time I owned an Aprilia AF1 Sport Pro but didn't have the money to do the conversion. About a year ago I built my first quadcopter. I found that there are lots of cool components used in RC vehicles. So I decided to build an electric bicycle out of them.

Straight from the beginning I realized that it would be too difficult or boring to build one that would fulfill all the regulations here in Finland. I wanted more power.

Here are the specs of the build:
Motors: NTM 50-60 270KV x2
ECS's: Hobbyking YEP 150A x2
Batteries: Zippy Flightmax 6s 20C 3000mAh x6 in parallel.

Some photos posted on bikepics: http://bikepics.com/members/perttup/electric/


And a video (with burnout):
[youtube]cJcY97ykuSU[/youtube]

I'm planning on replacing the cheap servotester-throttle with Arduino based system. This one is dangerous, it might suddenly hit full throttle. And I dont have a kill switch. I ordeded one from ebay, that will be a great improvement.

I also need to build better footbegs, these bend under pressure. And rearbrake would be nice, too. Let's see what this project brings with it.

I'm also about to buy an Aprilia RS 125 without an engine. It will be my next long term conversion project targeted to finish end of the decade.

How did you put the sprocket on?

There is a hex nut welded in the 11T sprockets. Those are then screwed to the M8 prop adapters.
The 32T sprocket on the left side is bolted into the original front sprocket from another bicycle.
11T on the right side the bike is welded to a cut crank arm.
70T sprocket is welded to the original casette.

That's probably the hardest part of the build. Luckily I had my dad helping me, he did all the lathe work and welding for the sprockets.

Add two ripple-suppressing capacitors to the inputs of each ESC. they are only $2 each. The 50V units are the most popular for 6S-10S batteries.

http://www.endless-sphere.com/forums/viewtopic.php?f=30&t=22194&start=25#p382837

Looks like you had a Meccano set once. :lol:

spinningmagnets said:

Add two ripple-suppressing capacitors to the inputs of each ESC. they are only $2 each. The 50V units are the most popular for 6S-10S batteries.

http://www.endless-sphere.com/forums/viewtopic.php?f=30&t=22194&start=25#p382837

Click to expand...

and also some out rigger bearings on the motors

Thanks for your comments!

I didn't yet read the other topic about ripple voltages. Is there any simple way to figure out right capacitance without an oscilloscope?

By rigger bearings do mean to add bearings to the other end of motor shaft? I've been thinking about that, but since this probably won't have too many miles I haven't yet put effort to design those.

And I never had Meccano set as a kid, that's maybe why I feel need to build stuff with aluminium profiles as a adult.

outrigger bearings will need to go on the end of the shaft where the sprockets are to help prevent any flexing under load from the chain pulling down on the motors.

Finally got fuse / kill switch for the bike and proper throttle grip. I was using servotester as a trhottle eartlier. I connected the throttle to a Arduino Nano to convert the signal for the esc's. No other improvements yet, i definitely need better footpegs.

[youtube]2I3cUcnOpx8[/youtube]