The Mid Drive Hub Motor Media Group

[John in CR]

I'm looking to shorten the axle to save some weight, and more importantly cut down on the maximum width. Both sides are hollow, one for the wires and the other for a shifting rod. The wiring harness is so tight that I'd rather not replace it, so I can't get it too hot in the shortening process. How would you guys cut it? I'm leaning toward short periods with the angle grinder and cool it off.

Also, what about attaching the sprocket? One side is cast iron/steel that extends to the opposite side of the magnet ring. The wire side is a more typical AL cover, though I think I'd want to reinforce it or turn a new thicker one if I drive off of that side. I'm expecting to run 6-10kw peaks depending on voltage.

Lastly, being quiet is important. I'm looking at a 3:2 possible as high as 2:1 reduction, so what chain and sprockets for a budget oriented guy like me?...the 218 stuff LFP swears by? I was even thinking bike chain at least until I'm sure about gearing, but use chainring size sprockets to greatly reduce the torque load.


John

[Whiplash]

If you have access to a lathe that's how I do mine. Just tie up the wires and carefully cut till thin enough to break off..

[John in CR]

If you have access to a lathe that's how I do mine. Just tie up the wires and carefully cut till thin enough to break off..

If I cut the wires a few inches from the axle, that could work. Thanks for making me revisit the idea of using a lathe. With the phase wires shorted, I might be able to do it just chucking the whole motor in the lathe.

[jull31]

Motor bafang BPM 500w
Battery 4 zippy 6s for 44.4 V, 10 Ah
Max speed 50 km/h and 5 Wh/km
http://www.youtube.com/watch?v=ESPSq6J0 ... r_embedded

[bzhwindtalker]

I miss my velomobile... I really can see how nice a mid driven velo would be!

last mid drive vid for a while, you will understand why at the end of the vid

[knoxie]

ahh damn what a shame...any chance the frame still has any warranty on it? great bike super agile, hope you get it sorted and get posting more videos soon

[Haste]

any benefit of using a smaller geared hub motor? Q series or bpm? It would even have more oomph on 48v than a DD...

[Alan B]

Video blocked for copyright content.

[Harold in CR]

American censorship. Video works for me.

[Whiplash]

Ha typical USofA

[bzhwindtalker]

[jateureka]

subscribed

[bzhwindtalker]

I made a new swing arm for my bike, new vids comming!

Also, this picture shows how the motor mount double up as a chain guard, not expected but really nice feature :

[Timma2500]

Also subscribed*

I like this build!

I hope the new swingarm works out well


Paul

[gwhy!]

I made a new swing arm for my bike, new vids comming!

I know you have a frame fail as well as the swingarm and I cant help thinking it maybe to do with the weight and position of the hub motor within the frame, Just a thought .

[bzhwindtalker]

I can't see how a mid mounted motor could be worst than a wheel mounted motor...

The swingarm I built failed too, badly engineered and d
oing huge jumps...

[amberwolf]

I like that setup...but I would ask that next time you take pics, you take them of the sunny side of the bike.

[bzhwindtalker]

This is my new signiature video :

[spinningmagnets]

From Rassy, please note that Rassy has the mid-drive motor use the BOTTOM of the freewheel to add power to the chain...

http://endless-sphere.com/forums/viewtopic.php?f=28&t=18606


Same guy, different trike:

http://www.endless-sphere.com/forums/viewtopic.php?f=28&t=47043

[spinningmagnets]

The M55, I know this is a low-production / high-Euro bike (Ferrari?) but I'd like to add it here simply because it shows that a well-researched project that can afford to do whatever it wants has studied E-bike drive systems,...and came to the conclusion that a hub driving the Bottom-Bracket (BB) is the best they could come up with.

In the interests of full-disclosure, I am working as a copy-editor (spell-checker?) for the electricbike.com web-magazine, and I have nothing to sell.

http://www.electricbike.com/m55/

[spinningmagnets]

From LI-ghtcycle, I know this hub-as-a-non-hub is mounted to the cargo rack, but...it seemed appropriate, since I'm thinking this thread will become a magnet for non-hub research. Its a 9C driving a right-side chain to a twin-sprocket NuVinci hub. Claiming high efficiency, very believable.
http://endless-sphere.com/forums/viewtopic.php?f=3&t=25082

[spinningmagnets]

Here's the Super-V from "John in CR",
http://endless-sphere.com/forums/viewtopic.php?f=6&t=26932&start=15#p389622

[spinningmagnets]

John in CRs bike had the rear suspension arm welded with an extension to make room for an easier install of the mid-drive. For those who don't have access to a welder, I was able to make a longtail full suspension by attaching the BB-axle of an MTB rear-sus arm to the drop-outs of a hardtail. It was easier than I thought it would be. I can fit a 10-inch diameter skillet in the extra space, so an 8-inch geared hub would easily fit.

[bandaro]

So I am seriously considering a hub mid drive to replace an outrunner for my next build, as I am currently having problems with snapping chains and tearing sprockets with my current build, the noise is tolerable, but I want something that is perfectly reliable.

So the reason I am avoiding a hub is the weight, currently the reduction for my 63-74 is well shy of 2kg all told, inc. motor (except crank/freewheel weight) and would take up a similar/smaller space to a hub motor. So as a result of the weight loss, I have a few kw in a bike well under 20kg, with 500wh of lifepo4. I am wanting a dual suspension, with lipo, and pretty sure I will be able to get the setup for under 6kg extra, but I hear that hub motors are very heavy, and the motor itself will be 6kg....

Never owned a hub, so don't know the weight for sure, but what would be the lightest hub that will push out 3-4kw? I am happy to overvolt it if it will handle it, just literally looking for the lightest way to get a hub running, so I can use all the hub motor components for reliability, and an off the shelf freewheel and bike chain going to the cranks. End result MUST be compact and clean.

Thanks for the input guys, I'm sure if there is a suitable motor out there, someone here knows it.

[spinningmagnets]

Geared hubs are common, and they are noticeably smaller in diameter than the direct-drive 9C-style of hubs. If you want the silence of a DD and you also want the small diameter of the geared hubs, Crystalyte no longer carries the 40X-series, but they do now carry the "G-series".

http://endless-sphere.com/forums/viewtopic.php?f=3&t=34203