Micro/Mini front hub motor?

[z0mb13e]

Hi All,

Been a while since I posted here... 2009 Wisper is still running (a now much reduced commute) on the original battery and the Cyclamatic will be up for sale as spares and repairs soon (never did find a replacement controller).

Anyway, I am thinking about buying a hybrid and converting it to a discrete lightweight ebike and was wondering if anyone knows where I could source a micro front wheel hub motor?

When I last followed the forum regularly, micro/mini hub motors were starting to appear, but now I can only find this one

by Falconev. Its 300W not 250W .

 

[Deleted member 4366]

There's the Q75 from BMSBattery. It's a little noisy though. It makes a sort of turbine noise. I've only seen it sensorless, so The nice sinewave controllers from BMSB are out. There's the Bafang SWXU. BMSB used to do that, but I'm not sure if they still do, otherwise you can find it on Aliexpress. The lightest one is the Keyde that you can buy direct from them or from Alibaba. They have a complete lightweight system including a battery. For a slightly bigger otor at 2.2kg, there's the Q100CST for rear drive and the Q100H for the front.

That Falcon EV one doesn't seem to freewheel very well!

 

[z0mb13e]

Nice - Thanks!

Keyde looks perfect.

 

[gibbon]

I have a keyde hub for sale, check the classifieds and get in touch if you are interested.

 

[z0mb13e]

I saw the classified and would have taken your arm off if it had 36 spoke holes.

I have a keyde hub for sale, check the classifieds and get in touch if you are interested.

 

[Deleted member 4366]

What's wrong with 32 holes?

I would have thought that it would be the speed that put people off.

 

[z0mb13e]

Nothing wrong with 32 holes, just wanted to stick with 36 as that seems more common.

Hadn't got as far as working out what RPM motor I would need.

 

[z0mb13e]

Hadn't got as far as working out what RPM motor I would need.

Rough calc, aiming for 25kph gives me 208 RPM for 26" Rim with 1.75" tyre (~2m circumference). Does that sound about right?

 

[Deleted member 4366]

If you want to travel at 25 km/h, you should get a motor with about 220 to 230 rpm.

36 holes is not more common on bikes, though it''s more or less standard for electric hub-motors. There's no advantage or disadvantage of 32 holes on a Keyde motor. You probably get a wider choice of rims with 32 holes.

160 rpm is 12 mph in a 26" wheel!

 

[z0mb13e]

I'm aiming for road legal (25kph is the assist limit isn't it?), doesn't break spokes too often and I can buy common spares off the shelf from a local bike shop.

From looking around for wheels and spokes a while back, 36 spoke rims seemed more abundant. Perhaps that was a coincidence, driven by my searches.

What about Sheldons advice?

 

[Deleted member 4366]

Mini/micro motors don't have enough torque to break spokes, even if you have only 32.

 

[z0mb13e]

Mini/micro motors don't have enough torque to break spokes, even if you have only 32.

Good to know. Thanks.

I'll just have to put in more effort up hill!

 

[jerrysimon]

Having used Keyde hubs for a year or so I have mixed views. On the Brompton my first one lasted about a year before it became quite noisey. Continued to work but I like stealth and went back to the standard Tongxin.

I have also put one on a larger 700c wheeled bike but not used it much and I have heard they prove even less reliable in larger wheels.

I still think the standard Tongxin motor is the best/most reliable option if you want stealth. Note the Keyde motors I have do not have built in controllers and I use external controllers to limit the power considerably. I have a 36H one built into a 700C wheel but its 260RPM so way above street legal in terms of max assist. To get round that I restrict the speed and current using the external controller.

Having said that for the last six weeks I have been cycling to work and back (10 mile round trip) with no assistance encouraged my daughter who got a job where I worked, gave up her electric bike she needed because of medical issues and we meet half way.

I think we will probably go back to motor assist when the nights draw in and the wind starts to blow lol

If you dont need stealth then as Dave said there are other options with the Q75.

Here is some background reading when I purchased my first one back in 2012

http://www.pedelecs.co.uk/forum/threads/new-super-light-tongxin-motor-design-kit.11035/page-5

The advantage for me of an external controller is you can fit a throttle as the inbuilt one pretty much restricts you to pedelec. I prefer to apply power just when I need it only.

Regards

Jerry

 

[z0mb13e]

Thanks for that Jerry.

Keyde setup looks perfect but is a bit pricey for the whole shooting match.

Might have to consider alternatives.

Stealth would be nice, but isn't essential. Discreet to look at if nothing else. I think i'll mull it over for a while.