Looking to replace a hard to find wheel and hub motor

[feordin]

8 years ago I managed to get my hands on a unique vehicle, an electric quadricycle, with a roof solar panel. My family has loved it and driven it regularly, but one of the two wheelhub motors has finally died.

It is a bit unique. 20" 350w, side axel with cable thru axle routing. Also, the bike has some sort of regenerative or motor-based braking. I always assumed it was a direct drive motor, but when this wheel died, I popped it open and there is what appears to be nylon planetary gears.

The bike has a single controller which handles both motors.

Any advice on finding a replacement is appreciated!

 

[fill]

not an expert and never seen a bike like yours.. but initial reaction is the regen braking has probably got more to do with those odd belts on the front wheels ?? tho i could be wrong,,

great bike btw!!

What is the motor problem?? some issues can be easily or more easily addressed

 

[feordin]

Regen was definitely using the rear motors. The belts on the front are actually connected to the pedals. So it's AWD . Pedal the front, power in the rear.

As far as repairing the rear motor, It doesn't look good. The screws holding the motor together finally weakened, I didn't notice in time. Dirt and other items got in. The nylon gears are badly damages, the remaining screws are bent, and overall seems badly damaged.

 

[Alex12345]

It can still be easier to repair, replace all the gears screws maybe even the whole core etc than to find the same hub. Because it seems quite special. I looked it up and only found this 20 INCH ALUMINIUM ALLOY ELECTRIC BIKE SINGLE SHAFT HUB MOTOR WHEEL MT921D – Sharpbike https://www.alibaba.com/product-detail/Sharpbike-Electric-Bicycle-Hub-Motor-One_1600107406795.html you can inquiry them about their minimum quantities or maybe they can send you one as a sample or a "customized" version idk.

 

[99t4]

Also, the bike has some sort of regenerative or motor-based braking. I always assumed it was a direct drive motor, but when this wheel died, I popped it open and there is what appears to be nylon planetary gears.

Right, geared hubmotors are usually not able to regen (they usually have a freewheeling clutch), but can be modified (locking the clutch)(or other even less-common mods).

You should be able to test by spinning the wheel. Normal freewheeling clutch will allow easy spinning forwards, but with much more resistance when spinning backwards.

Using a geared hub motor with regen?

Hi ES, I have been playing around internet all morning but can't find good info.... Has anyone ever used a geared hubby with Regen either by disabling the freewheeling or are there any geared motors without freewheeling? I know this could damage the gears but still interested. Thanks

endless-sphere.com

 

[E-HP]

I’m guessing the motors need to be matched, so if you can’t find the exact replacement, will you be replacing both?

The Grin all axle hub motor has a single side application that might work (can’t see how yours is mounted).

All-Axle Hub Motor - Grin Products - Our Products

The All Axle motor takes the simplicity and robustness of the direct drive hub motor, and optimizes it for the modern bike platform. This hub is fully compatible with all quick release and thru-axle bike forks, it is over 30% lighter than standard generic hubs of similar power (4kg vs 6kg), and...

ebikes.ca

 

[offGridDownUnder]

Not only does Grin offer single-sided All-Axle motors, they provide a custom 20" wheel for arrangements like yours, as well as the electronics to use them. The All-Axle is DD (no internal gears) and provides regen.

If you don't find a way to repair what you have, you might instead see about adapting the remaining machine as needed for the replacement wheels.

Grin All-Axle Hub CBW3 20" Cargo Wheel

 

[fill]

Regen was definitely using the rear motors. The belts on the front are actually connected to the pedals. So it's AWD . Pedal the front, power in the rear.

As far as repairing the rear motor, It doesn't look good. The screws holding the motor together finally weakened, I didn't notice in time. Dirt and other items got in. The nylon gears are badly damages, the remaining screws are bent, and overall seems badly damaged.

so much for my initial take then.. ha - now i can see the belt path DOH!. - Again Great Machine certainly worth keeping on the rd inho..

Post more pics of the motor and the damage.

Gear sets etc are available via portals like ali express, chances are high the collective wisdom in here can easily identify the parts and keywords for any replacement searches.. Youtube vids aplenty to help ease you into comfort with any task

And you can probably look forward to becoming an expert in machine screw head options when tracking down replacements,

 

[feordin]

I thought I would add summer photos of the motor/wheel. Several screw holes which hold the two halves of the motor together are badly damaged. Internal gears are damaged as well. I'm not sure how to repair it.

 

[offGridDownUnder]

Not to make the decision for you, but to explore options, I revisited the Grin wheel I mentioned above. That shows no option for a brake rotor. However, if you accept a regular spoked bicycle wheel the single-side V2 All-Axle will certainly provide a brake rotor as well as the motor, so I can suggest replacing your rear wheels with that as an option.

I can't speak to your finances. Can you tell what the frame is made of at the rear where the two hubs mount? If it's steel, or if you know a good alumin(i)um welder, then at worst you can replace the wheel mountings there and have a working machine and a path forward. I would expect a long life with the Grin DD All-Axle. With that that choice, at worst you can also replace the motor controller to gain full use if the existing controller does not interface.

The existing motor appears to rely on axle flats to prevent spinout. The All-Axle provides the needed torque arm instead, which would be far superior, and removes the need to handle that with the axle mounting. It may be possible to simply run a straight (perhaps tubular) shaft across for both rear wheels to mount to with the thru-axle mounting option inserts for the motors. That is, you'll need to accommodate the brake caliper mounting and the torque arm, but the rest might be easy, and your existing brake caliper mounts may already also handle both that and the torque arm. The change might be simple.

Is the existing controller one you understand, or can find docs for? Perhaps you can provide details/pictures here in case someone here knows about it.

Pictures showing the rear wheel mountings would be interesting, although your fabricator/welder's input might be more important.

 

[Alex12345]

I thought I would add summer photos of the motor/wheel. Several screw holes which hold the two halves of the motor together are badly damaged. Internal gears are damaged as well. I'm not sure how to repair it.

Maybe it's possible to find a replacement disk brake side cover and gears, if their size is similar to normal 250w geared hubs.

Also, I checked that sharpbike wheel I referenced earlier, their kit 20 INCH DUAL DRIVE HUB MOTOR KITS WITH REVERSE AND REGEN BRAKE – Sharpbike lists reverse and regen, so their single side motors must also have a locked clutch / no freewheeling just like yours. Not sure if reduction ratio is same, but since you have the motor disassembled maybe you can check.

They list a motor wheel sample for $105, but not sure how much is delivery, and idk how difficult it is to do business through alibaba, but theoretically trying to request a sample seems possible at least.

Switching everything to Grin will probably be like over $2000.

 

[feordin]

Thanks for all the input! I started a conversation with sharpbike on Alibaba, we'll see what they say. I'll also look into the Grin option

 

[Apartunis]

This one is reasonably priced and efficient, well proven and direct drive.

48V 52V 1500W single side shaft hub motor

Convert your original wheelchair, tricycle to be electric with leaf 48V 52V 1500W single side shaft hub motor.

www.leafbike.com