[sharp21]

The treadmill here at work is opened up for maintenance so I took a look at the motor. Here are the specs:
3HP Continuous Duty @ 13vDC / 2672watts
It is 11" long x 4.5" dia, with a 1.5" shaft.
There is a also a fan connected to the end opposite the drive shaft.
So would this be a decent bicycle motor?
S.

[n8thegr8]

that motor's a beast! most of the ones I've been lookin at are electric scooter motors around 800W and 36v. That motor could probably do burnouts, lol. It's cool that it's only 13 volts, but it would pull some huge amps, so you might have to do something tricky as far as the controller and batteries go. It would be an interesting conversion for sure. I'm building one with a custom controller, but I'm building it to handle about 160 amps with an 800w motor, I have no idea how much you would need to power that beast, probably a golf cart controller of some sort. I'm by no means an expert though, so take what I say with a grain of salt :P

[ngrimm]

Are you sure that isn't 130 vdc instead of 13 vdc? Otherwise that would be like 205 amps. I just checked ebay and found this one that may be close: http://cgi.ebay.com/Nordic-Track-DC-...QQcmdZViewItem

[sharp21]

Yup thats pretty much exactly what it looked like. It had a fan on the shaft that sticks out the non-drive end.
So what about that as a drive motor on something?
S.

[n8thegr8]

ahhh...130v, that makes more sense now, lol. Well, it would probably be better suited to a motorcycle, because to get that voltage you'd need 11 12v batteries, even on a motorcycle you'd have a hard time finding a place for all of them. Could be interesting, and would probably get you some pretty sweet performance due to the high voltage, but I think the batteries are gonna get ya.

[Mastiff]

You could achieve that kind of voltage with Lithium batteries as they are light and high voltage.

If the motor is rated at 2672 watts then 2672/130 = 20.5 Amps would be the amperage draw of the motor.

In that case you'd want a 20-30AH pack at least so that you don't stress the batteries.

A 130 volt 20 AH pack would contain 2600 watt-hours and if your bicycle used 100 watt-hours or less you'd get 20 good miles of range out of it.


The only problem would be getting a controller for that high of a voltage that wouldn't cost a ton, or be too big because most are designed for higher amps also.

I don't know of any controllers in the 120 volt range that aren't designed for larger EV's.

[johnnyfoos]

I also have a treadmill motor around that rating,
2 1/2 HP, 120 VDC
I'd been wanting to test at lower volts, but have not had a chance yet
Good luck

[Amberwolf]

Thread necromancy:

For those looking to do this, it should be possible to use a treadmill motor (generally designed for 100-130+ VDC) on an ebike without using voltage that high, depending on the speed and torque you're after.

I've got one here that I've played with a bit, and even at 24V it has enough torque when suitably geared down to make me think it would operate as desired at least at 36V. Some videos of the test rig are here:
http://electricle.blogspot.com/2009/...ybike-v20.html
along with explanations, comments, etc.

One issue with using these is that at least some places regulate the amount of power you can have on an ebike, unless you register it as a moped or motor-driven cycle, with insurance/license/etc. Most of the limitations are 1HP or less, while most treadmill motors are higher capacity than that. Theoretically, undervolting or otherwise hardware-limiting the motor so that it's actual output power can't be that high should be enough to satisfy the law, but I don't know that it's been questioned in court yet.

That's the theory I'm running under for my own use of one, however. I did not end up using it on the Crazybike2 (the bike being developed in the videos), but I will probably be using it in the recumbent tadpole trike I'm working on now.

[johnnyfoos]

Hello all,,..

I have another question about "Treadmill" motors-
The stock controller
is it of any use
like, for using DC volts
and not AC
?
I saved the controller when I got my motor,
had to tear it apart on lunch, dang thing was to big
to fit under topper shell on my toyletta, so
I grabbed what I thought might be good, belt was wasted.
$5. wasted on stuff that will not work well for wind turbine use
but,
EV play might be good.

[Amberwolf]

Well, if it's like the treadmill I have here it uses an SCR rather than MOSFETs, after the bridge rectifier and filter cap, to slice the voltage.

On mine, the PWM input (the actual "controller") comes from a different board--the one up in the main console with all the displays and such. It's not usable in anything else because it is part of the microcontroller-based custom boards that run those displays, input buttons, etc.

So even if you modify and use the power board, you'll still have to likely build the more complex part of it--the PWM section.

I'd recommend either building one from scratch, or an existing open-source design (which range from very simple but not necessarily protected against all the potential gotchas from motor control, to very complex but extremely robust), or simply buying an off-the-shelf one if you're not completely comfortable with building your own.

The PWM part is easy to design and build, but making a power-handling motor-drive section that can withstand all the oddball things that very occasionally go wrong (especially with MOSFETs at high power), that's not as easy. Easier nowadays since there are a lot of pre-made driver chips and such, but it takes research to find the ones right for your application.