NEM0 - <$1k Electric Dual Sport

[Robomaniac]

I really like what you did!

Can't wait for "NEM0 2 - >$1k Electric Dual Sport"

[captainslug]

Quick update after I took a long break from this project.
I would like to retest this bike at 60 volts, but first I need to install a much stronger freewheel.
I managed to grind down and remove the motor linking sprocket, found the previous destroyed freewheel, and remove it from the freewheel adapter.

So next I need to
1. Order this freewheel

http://sickbikeparts.com/catalog/produc ... ucts_id=62
2. Attach a sprocket to it at the right spacing
3. Install it on the freewheel adapter
4. Make a replacement motor-link sprocket
5. Reconnect chain drive
6. Swap out the battery charger
7. Reinstall 5th battery

[captainslug]

Good news: I found the original footpegs and thefront brake rotor in a box at work.
I reinstalled the rear foot-operated brake which will give me more control and safety. Especially when the roads are wet (when front brakes are almost useless).


Now I just need to buy a new freewheel and get the chain drive back together.

[Thud]

How did i miss this build?????

Very nicely done CS.
I read through a couple times looking for the doner chasis make. Is it some china import?
great job on the lighting & fit. I like everything about it.

[captainslug]

I've ordered a 2.65HP treadmill motor to be used as hopefully the last and final power plant for this project. Its rated for 2.1kw peak, 1.6kw constant @ 95VDC.

And here's what I eventually want the frame to look like. Whenever it is I can get around to painting it.

I read through a couple times looking for the doner chasis make. Is it some china import?

A very chinese Xmotos XB-31XT.

[captainslug]

Motor arrived today. It's the perfect size, weight, and ratings. It also includes a hall effect switch for monitoring RPMs which will be very useful because I will need to use that in order to select the right gear reduction ratios.

I will test it at 60 volts with the controller tomorrow.

This motor spins so smoothly I'm contemplating not bothering with a freewheel. If I do ditch the freewheel I have the option of later adding motor braking of some kind (regenerative or not).

[vanilla ice]

Sweeeet, how much was it?

[j3tch1u]

fantastic build--one of the best i've seen. you should take that to production!

[captainslug]

Yesterday I removed the pair of motors and started work on designing the revised motor mount.

I'm waiting on a laser tachometer to arrive in the mail so I can measure the peak RPM of the motor at 60 volts. Then I can determine what reductions are needed.
The drive shaft of the motor unfortunately has a mix of imperial and metric dimensions. The tip is left-hand threaded 1/2-13, but the rest of it is 17mm.

I'm probably going to end up making a V-Belt pulley for it from scratch.

Edit: And now I have the motor mount finished.

Sweeeet, how much was it?

$90
Used treadmill motors are very easy to find at reasonable prices. This one was brand new and unused.

fantastic build--one of the best i've seen. you should take that to production!

Thank you very much.

[captainslug]

Motor-mount finished and assembled. Can't do much else until I have a tachometer with which to measure the motor with.

However if the tap arrives in the mail today I will be able to finish the custom drive pulley.

[Jay64]

That right there is beeeautiful. Awesome work. Great build too man.

[captainslug]

And now the custom pulley for the motor is done.

[captainslug]

Laser tachometer arrived yesterday. At 60 volts the motor reaches a peak of 3600 RPM.
That's quite a bit faster than I was expecting. I will have to use two reductions to achieve a top speed of 40mph.

3.818 : 1 (41t : 11t)
1.4 : 1 (25t : 35t)

I won't have the option of using a belt at these speeds unless it's a timing belt. But those are just too expensive for me right now.

[Tom Tom]

That bike is screaming for an Astro 3220 setup

[torker]

Captn, I read through all of this at one time or another but I was wondering. Did you test it @ 48 or 60 volts before the freewheel toasted? Looks good btw I love the fabrication.

[captainslug]

That bike is screaming for an Astro 3220 setup

Something I'll contemplate when I'm filthy rich.

Captn, I read through all of this at one time or another but I was wondering. Did you test it @ 48 or 60 volts before the freewheel toasted? Looks good btw I love the fabrication.

I tested the pair of motors at 60 volts and reached a top speed of 38mph. They got kind of warm though.

[mwkeefer]

That thing is SICK - very cool looking, a little under powered (my folding bike hits 4200w+) but very cool all the same!

-Mike

[torker]

What is the reason for switching to the treadmill motor? Are you hoping to get more power out of one simplifying the setup? that bike does scream for an astro or mars/etek. I know about the thin wallet thing though

[captainslug]

The sprockets are ordered. Hopefully I can get the chain drive done within the next week.
And better still, a bunch of the guys at work (myself included) are pitching in to buy sand-blasting equipment.
Perfect timing since I that will be the final step in completing this project.

That thing is SICK - very cool looking, a little under powered (my folding bike hits 4200w+) but very cool all the same!

-Mike

Yeah, the peak for this particular motor @60 volts will be around only 3kw because of the cheap controller I'm using.

What is the reason for switching to the treadmill motor?

It's all-around a much more durable and powerful motor, which is also rated far above my intended voltage. If I want more speed later, I can simply up the voltage of the battery pack and controller to reach closer to what the motor is rated for.
Having a pair of motors was also a considerable amount of extra weight to add to this bike. The treadmill motor setup is 20 pounds lighter.

[captainslug]

Replaced the 4awg wires with aluminum bus bars.

[captainslug]

So a bunch of the guys at work pooled together to buy a sand-blasting cabinet. I ran out of work to do by about lunch time so I spent all afternoon and most of the evening using a grinders with brush wheels to strip the frame down to bare metal as much as I could, then used the sand-blaster to do touch ups in the difficult-to-reach spots. I then applied two coats of flat black Rustoleum.

The battery rack is also painted. I'll have more photos to share once the bike is back in one piece.

I apologize for not having any in-progress photos. But the work was really messy and labor intensive. I was afraid that if I stopped to take breathers and take some pictures I wouldn't have reached the point I wanted to be at by this evening.

[captainslug]

Hey Capt'n,

What controller are you using???

If it's a cheap YK-42x series changing a handfull of parts can take it to higher voltages...

Yep
http://cgi.ebay.com/ebaymotors/ws/eBayI ... 0452738030

[captainslug]

Here's the cleaned and painted battery rack I finished working on yesterday.

Reinstalled the electrical system, gauge console, front fender, and controls.

Vinyl dyed the fake exhaust hose black, and lengthened the wires for the turn signals so I could route them through it.

Seen inbetween the bushings is a set-screw collar I made which is flanked by thrust bearings. It makes sure that the axle doesn't slide in either direction.
I also installed the newer and stronger 22T freewheel on the adapter I freed from a previously destroyed freewheel.

I'm now simply waiting on parts to install the belt reduction.

[captainslug]

Bored out both pulleys, tapped one and on the other used a scroll saw to slowly cut a keyway into it.

I've ordered a belt, and parts to make a tensioner for the belt.

[zap]

Very nice build captinslug.
Incredible perseverance on the project... it's amazing how much time something can take when you don't have a set of instructions in front of you eh? And you've done an excellent job of documenting the whole thing.

Good luck with the treadmill motor. I'm using a similar one on a pedal generator and they're nice motors, 1.5hp @ 100v.