Ebike rr8.2 water-cooled q100

[Dani85]

My bicycle was born from the desire to express my creativity skills, giving shape to a uinique project.
I wanted a powerful and fun to drive bike, agile in the mountains and equipped with a long-lasting battery.
It was born in 2012 but over the years has undergone a lot of changes. The most important was the changeover from the rear hub to
to a new middle hub with a liquid cooling system.



I started from the choice of the bike and the motor: a Rockrider 8.2 and a 9C super torque rear Hub (5*12).





The first studies were aimed to select the cell battery and its housing.
Once completed the housing I started with the torque arms.
The torque arms were created by welding the original antirotation washers with the steel plates, shaped on the rear fork.Then I filled the weld joints with some epoxy resin and painted.



View attachment 23
The battery pack is a 24s A123 15ah, divided into two 12s packs to facilitate the charging phase (with robbe eternity).
To assembly the battery cells I used a 6mm copper bar and a 1mm copper strip, all closed up with two 3mm screws.
View attachment 22

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I chose not to use the Bms, but to charge the battery pack with a modeling charger.I can constantly monitor the battery usage, displayed by the Cycle Analyst, and I never go below 40% soc.






The frame shield is made of thermoformated PVC, but for the early testing I used a common plexiglass.

I create the frame support to fix the anterior light and the plastics body.






The controller is based on chip infineon. I changed the condensers and replaced the mosfets with Irfb4110.
View attachment 5



I changed the original wiring with 8mm cable for power section and 0,5mm cable for the auxiliary.


The wiring leaving the controller in a protective sheath to protect the wires from dust and water.


Some parts of the body are coated with 3m carboon look.

 

[Dani85]

View attachment 3

 

[Dani85]

The bike performance with the 9C hub was impressive, reaching 40 km/h on flat ground and very funny uphill.
After two years of use, in a hard climb I burned the motor with 63A current.

At that point I had to find a solution without spending additional money. I already had a unutilized q100 hub motor at home, so I thought I could use it as
middle motor and started to design the housing ...

 

[Dani85]

To preserve the bike's aesthetics it was necessary to disassembly the hub to find the most suitable solution.
The first step was to create a tailor-made tool to unscrew the cap of q100.
View attachment 13
The q100 was the ideal motor because not having a continuous axis it was possible to fix it by one side thanks to the exhisting hole of the axle.





Once made the stirrup to fix the motor, I created a "back-stirrup" to support the motor on the pinion side.





To lighten the stirrup I drilled it, but then I realized that all those holes had weakened the structure, making the stirrup easy to flex when the motor required more power and causing the fall of the chain.
That's why I created a new stirrup made of galvanized steel, very strong and durable.
View attachment 5
I also added a bearing on the q100 cover to make it more stable.



I used a 13t pinion, welded with three bolts that go in the same holes of the hub cover in order to ensure the pinion not to unscrew.
Limiting the engine control unit to 40v the motor didn't overheat that much, but after some tests at 80v I burned
the stator!


Noticing the incredible power developed by the q100 at 80v I wondered if it was possible to create a cooling system for the stator.

 

[Dani85]

After several attempts I finally succeeded: I had my liquid cooling system worthy to be called so!
I took a radiator of a dehumidifier and sawn it in 4 smaller radiants in order to house them behind the mesh.




I built a copper tank and soldered, took a 12v pump for liquids and made a spiral to wrap the stator of the q100.





The chassis of the q100 has been lightened and drilled to make the air circulate better.
To monitor the temperature I have also assembled a thermometer with display.


View attachment 4
The bike develops a nice power, in first gear the speed is 23 kmh, in the last gear reaches 80kmh!
Proceeding at a medium speed (30KMH), the temperature is now stable at 35 degrees celsius.

Only a long time at maximum speed with current peaks at 60A make the temperature increases till 55 degrees celsius but thanks to the cooling system the stator now is safe.

 

[spinningmagnets]

This is an impressive first project. I am glad you posted this. Grazie!

 

[AngusR]

Nice job on fitting your water cooling system on there. Looks like you had a lot of chances to get creative with this build

 

[skeetab5780]

ya this build blog was pretty sweet! thx for posting. Any chance of a vid?

 

[Brake]

Wow, a lot of work! Very creative. Nice job. Thanks.

 

[Dani85]

Thanks everyone for the compliments, I'm so happy for sharing with you my creation!
I not have a youtube channel for upload bike videos..

 

[boisrondevens]

Wow! verry good.

 

[Drunkskunk]

80 volts and 60 amps through an Adana Cute Q100?
That's seriously impressive.

 

[cwah]

Looks nice but... isn't it simpler to just get a bigger mid drive motor?