Complete Details of Zen Mid-drive Motor - 500W (900W peak) power, 120Nm torque

[Ravi Kempaiah]

We had received several questions regarding the motor we used on our photon bikes. So, we would like to share some details here.

Why this Zen custom motor?
When we first released our Samurai model with the Bosch Gen-4 motor system, people really liked the motor but we often received requests for two things:

• Throttle feature
• Slightly more power than 350W

Bosch is a fantastic system for those who like to pedal but we also believe that the Throttle feature can be very useful for more folks to get into biking. Also, many folks get an E-bike after several years of not being active, so they would certainly appreciate slightly more power. USA laws allow 750W, and Canada allows 500W nominal power. Why not make full use of that?
Well, Bosch is not going to allow throttle feature anytime soon and we can see value in being able to offer that along with slightly more power. So, we decided to work with a reputed motor manufacturer to customize a system for ourselves. [Read details below]

What were the criteria for developing a custom Zen motor?

• Very smooth power delivery + reliable torque sensor
• A minimum of 120Nm torque at the crank
• being able to run at 52V ( as we are harmonizing our battery pack architecture to 52V)
• A min of 500W nominal power and 900W peak output
• Parts availability well past the warranty period, and N.American support
• Throttle support up to 20mph or 32km/hr
• Automotive grade connectors and IP X5 protection
• Less than 4kg in weight
• Minimal lag when it comes to pedal assist sensor (PAS) engagement
• Willingness to collaborate and develop firmware for N.American market
• ISIS crank for durability (not square taper crank) and crank selection

When you get into the world of motors, you realize so many nuances that are not visible to the common market. For example, several reputed motor manufacturers use torque sensors made by one company in Asia, and what differentiates them is their controller architecture and quality. There is so much difference between the QC/QA from manufacturers. We approached some big names, and their minimum order quantities were quite high and they were unwilling to make the requested changes. We were very clear that we should be able to program PAS sensitivity, and the torque sensor must be reliable. If we could run the motor at 52V, it would help maintain higher torque and 28mph speed. So, we started the project in early 2022 and tested prototype bikes for over a year before getting into production.

Selecting a manufacturer to work with:
For custom Zen mid-motor, we decided to work with Ananda in Shanghai. We learned that Ananda was started by former lead engineers at Bafang (just like Lucid Motors was started by a former chief engineer of the Tesla Model S, and Ananda is in top-3 when it comes to the export market (over 1M units). They export both hub motors and mid-motors and they were a lot more willing to work with us and provide support than other manufacturers. We also learned how several EU companies license motor core design from Asian companies (including brands like MAHLE that make Specialized motors). We considered several motors Bafang, Dapu , Truck Run, Vinka (no 52V support), and Brose (no throttle or 52V support).
Finally, with Ananda,

1. We were able to tune the firmware to offer smooth pedal assist
2. Get the motor to run at 52V.
3. Higher wattage light output
4. We can stock parts and provide high-quality support to N.American customers.
5. Get excellent support for our assembly factory.
6. Higher-quality QC/QA and you can see the factory pictures below.

Is it used by Other manufacturers?

From what I know, several EU manufacturers work with Ananda. In the USA, we have learned MAGNUM Vertex has a 48V Ananda motor, and
Surface604 are working with Ananda for their 2024 model. Priority and Lectric work with Truck Run. We know of several other companies working with Ananda.

For Zen, we are now able to use our in-house batteries to offer long-range, and starting March 2024, our batteries will carry full UL certification and we have received very positive feedback from our customers so far and this is important for us.

 

[vincent]

great write up and very good information to have

 

[WildPaul]

Awesome, love the transparency.

 

[juggernaut]

Great summary of Ananda motors and why you chose to use them.

My wife and I have the Ananda motors (48V version) in our Australian distributed Earth e-bikes and can’t fault them.

 

[Rome]

Whatever. I waits for zen for emtb full suspension.

 

[Gionnirocket]

Nicely done... you're always (very) busy in the background!
So is the plan to have Zen motors on all your bikes or will you still build Bosch/Bafang options?

 

[JGcycle]

Glad to hear that your batteries will soon have full UL certification.

 

[JRA]

Nice Ravi. While it is easy to see that ZEN is focusing on the commuter/touring market I am a bit jealous of that motor and wish I had one in a 150mm travel aluminum frame MTB....a good competitor to the Bafang M600/500 series motors making their way on to some EU manufacturer bikes? Fully behind the 52v program also as that is what I have settled on for my bikes, it is like a "why not?" thing. With your experience in battery construction along with controller architecture and the ability to have a throttle I think that if all goes well this motor will become a major sales factor for ZEN in N.America in any category you choose to put it in? I predict that when it becomes more well known that other companies will adopt it also so may be time to lock down a licensing agreement with Ananda!

 

[Ravi Kempaiah]

Nicely done... you're always (very) busy in the background!
So is the plan to have Zen motors on all your bikes or will you still build Bosch/Bafang options?

We will still maintain a good relationship with Bosch and Bafang. Ultimately, we want to supply batteries to all their E-bikes.

 

[Ravi Kempaiah]

Nice Ravi. While it is easy to see that ZEN is focusing on the commuter/touring market I am a bit jealous of that motor and wish I had one in a 150mm travel aluminum frame MTB....a good competitor to the Bafang M600/500 series motors making their way on to some EU manufacturer bikes? Fully behind the 52v program also as that is what I have settled on for my bikes, it is like a "why not?" thing. With your experience in battery construction along with controller architecture and the ability to have a throttle I think that if all goes well this motor will become a major sales factor for ZEN in N.America in any category you choose to put it in? I predict that when it becomes more well known that other companies will adopt it also so may be time to lock down a licensing agreement with Ananda!

'This motor compares very favorably against the M600, and I really think the Ultra motor is only for those hardcore riders. Not everyone needs an Ultra motor.
With oversupply of bikes from several companies, it is hard to stay competitive in the market, but we will continue to push innovation in the battery space.