Bosch Active Line 3 mid-drive motor tear down

For my solar powered bicycle, the Maxun One, I designed a very powerful and lightweight mid-drive motor. I also wanted to investigate whether I could use a Bosch Active Line 3 motor. The Bosch motor weight is 2975g, this is relatively lightweight for a mid-drive motor, but it is still too heavy for my solar bike.

So, I wanted to investigate if the Bosch motor can be reduced in weight, so I disassembled the motor. This is also a great opportunity to see how it works and which electronic parts are used.

See the whole article here:
http://www.avdweb.nl/solar-bike/hub-motor/bosch-active-line-3/bosch-active-line-3.html

What is striking after opening the motor is that there are only a few parts inside, that is a great achievement of the Bosch engineers:



See the whole article here:
http://www.avdweb.nl/solar-bike/hub-motor/bosch-active-line-3/bosch-active-line-3.html

A great tear down, and fantastic website by the way.

Have you figured out where you can remove any material to lighten the product up?

Beautiful engineering from Bosch and a nice tear down from you.
Some other light weight mid drives:
https://endless-sphere.com/forums/viewtopic.php?f=28&t=95704
https://www.gngebike.com/ultralight-300w-kit

And please show your own design here also.

avandalen, thanks for sharing!!

Really good to see the Bosch technology and compare to cheap chinese options like TSDZ2 mid drive motor: https://github.com/OpenSource-EBike-firmware/TSDZ2_wiki/wiki

Sure Bosch technology is more advanced but from the perspective of using the motor to other applications like hand bicycles, repair, DIY and having/owning knowledge about motor technology, cheap chinese like TSDZ2 mid drive motor is the way to go!!

robbie said:

A great tear down, and fantastic website by the way.

Have you figured out where you can remove any material to lighten the product up?

Click to expand...

No it is not possible.
I will switch to a Shimano Steps E8000 (2.88kg) or Brose mid drive motor (2.9kg in 2019)

See the article about the motor graph here:

https://endless-sphere.com/forums/viewtopic.php?f=30&t=100180

I have a question that I hope you can answer for me.

While trying to sort out a mysterious creaking sound from around the bottom bracket, I started to open the Bosch Active Line motor on my Trek e-bike. I opened the case a few mm to investigate but then realised I wanted to go no further and I tightened the bolts again. The noise was resolved once everything was reassembled - I think bolts just needed tightening.

I've now seen your information about the thermal putty, and am wondering whether I need to replace this. Will opening the case by a few millimetres have detached the putty from the case (or PCB)? Or does the PCB initially remain attached to the case after opening it?

Thanks, Dylan.

avandalen said:

For my solar powered bicycle, the Maxun One, I designed a very powerful and lightweight mid-drive motor. I also wanted to investigate whether I could use a Bosch Active Line 3 motor. The Bosch motor weight is 2975g, this is relatively lightweight for a mid-drive motor, but it is still too heavy for my solar bike.

So, I wanted to investigate if the Bosch motor can be reduced in weight, so I disassembled the motor. This is also a great opportunity to see how it works and which electronic parts are used.

See the whole article here:

Bosch Active Line 3

Here, I share technical solutions that arised during the development of my solar-bike.

www.avdweb.nl

What is striking after opening the motor is that there are only a few parts inside, that is a great achievement of the Bosch engineers:

See the whole article here:

Bosch Active Line 3

Here, I share technical solutions that arised during the development of my solar-bike.

www.avdweb.nl

Click to expand...

Can you remove and add an external controller.

dylofpoke said:

I have a question that I hope you can answer for me.

While trying to sort out a mysterious creaking sound from around the bottom bracket, I started to open the Bosch Active Line motor on my Trek e-bike. I opened the case a few mm to investigate but then realised I wanted to go no further and I tightened the bolts again. The noise was resolved once everything was reassembled - I think bolts just needed tightening.

I've now seen your information about the thermal putty, and am wondering whether I need to replace this. Will opening the case by a few millimetres have detached the putty from the case (or PCB)? Or does the PCB initially remain attached to the case after opening it?

Thanks, Dylan

Click to expand...