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Stephenj
Newbie

Joined: 05/07/2012
Location: New Zealand
Posts: 13

Posted: 04:53pm 07 Apr 2013

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Hi all,

I managed to get cassette on the hub.

Id ideally like to have a machined part for attaching the drive to the bike, so that its detachable and so I don't destroy the bike frame and it could also be attached to most other bikes too. I could modify the aluminum housing the drive came with but then Id have to try and bolt it to the frame.

if only I knew CAD/CAM..!

Stephenj
Newbie

Joined: 05/07/2012
Location: New Zealand
Posts: 13

Posted: 10:30pm 03 Feb 2014

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Hi Guys,

So I've decided to attach the smart drive to an indoor trainer, its a 42 pole 60 series (I think its 0.6mm, my digital vernia needs batteries). its wired as 7X2C and I've de cogged the poles. as you can see in the picture the wheel turns the drive shaft and with no electrical load it works well...

but with the load of a light bulb or AC/DC inverter its too hard to spin it.

there's a little room to fit a thicker 1 1/2 inch sleeve over the drive shaft thus making it a little easier for the wheel to turn the shaft but I don't think that will be enough..

is there another way I can wire up the drive to allow it to spin easier at lower RPM?

I have learnt a little TIG welding in the process :)

Downwind

Guru

Joined: 09/09/2009
Location: Australia
Posts: 2333

Posted: 12:27am 04 Feb 2014

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There is no reason you need to use all 3 phases, you could try dropping 1 or 2 phases out and just load a single phase (or 2), simply leave a phase open circuit.

Another method is undo the magnet rotor nut some, so it backs the rotor off of the stator about halfway, this is often done on hydro system to reduce load in times of low water flow.

No perfect answers but a few ideas to have a fiddle with.

Pete.

Sometimes it just works

Tinker

Guru

Joined: 07/11/2007
Location: Australia
Posts: 1904

Posted: 03:33am 04 Feb 2014

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" but with the load of a light bulb or AC/DC inverter its too hard to spin it. "

Remember: power out = power in + losses. Start with a small light bulb (~15W) and work from that to find a load that suits you.

Klaus

Stephenj
Newbie

Joined: 05/07/2012
Location: New Zealand
Posts: 13

Posted: 01:32pm 06 Feb 2014

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Thanks Guys, unscrewing the rotor and disconnecting one the AC cables did the trick nicely.

I'm getting 16.5v but I'm only getting 0.002amps? (according to the voltmeter) although it powers the portable stereo easily.

Sorry don't know much about this but I thought I'd be getting more amps..?

mission accomplished though.. :)

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