Usability of Bosch and Pendix ebike drives

Experience of 2.5 years of pendix on an e-Muli and half a year of Bosch on a Tern Vektron S10.

Pendix edrive

Our first Pendix motor died after a ride through snow, presumably because melting snow entered the engine. It got replaced for free with the more powerful 65 nm version on warranty, after I got told this was unfortunately not possible for money (Pendix service is renowned for being a bit weird).

The two 300 wh batteries generally work well except:

• The magnetic contacts sometimes attract (magnetic) dirt, so you have to blow that out to make everything work again. That generally works well, but can be annoying.
• When you take off the battery, the system‘s contacts are exposed to rain that can enter and prevent the system to work. I consider that a serious design failure especially because the neoprene cover is not included.
• Security: The batteries can easily be stolen unless secured by the little bar which is more cumbersome than Bosch‘s key lock. It might be less attractive and known to thieves but I wouldn’t want to take the risk.
• Charging: the charging stand looks and works great and can be easily dismantled for traveling. The flashing LEDs are well visible so you can easily see if the system is still charging before you fall asleep. The app indicates the duration until 80% of charge, so you can set an alarm to avoid charging more than healthy for the battery. An option to stop charging at 80% would make sense to me but Pendix just sent me a copy paste answer to that proposal. Even without app, the LEDs let you know when reaching 70 or 100%.
• No automatic switch off: a software design failure that can be quite annoying. You have to always manually switch off the system which can be easily forgotten especially at daytime. Bosch switches off automatically.
• App: the app allows you to check e.g for software updates, distance covered by the engine, adapting the assistance modes (torque and speed) and charging percentage / range. Bosch does not let you update their software but has all the rest covered by the handlebar device. The Pendix furthermore  indicates whether you pedal fast enough for the engine to run efficiently, which at least my oldish Bosch doesn’t let me know.
• USB power output: Pendix batteries come with a usb-c output which is however not well protected from the rain and cannot be replaced under warranty. So one of my two broke after less than a year I think.
• Assistance choice and surveillance: to switch to another of the only three assistance modes, you have to reach down as if to reach your bottle cage. That is much more cumbersome than using your thumb as in the case of the Bosch computer. Unless using the app (eating your phone’s battery via Bluetooth and screen use), you cannot see what mode you’re in, so you easily forget switching back down after a slope, resulting in a waste of capacity.

Bosch ebike system

• Our Bosch came with a 400 Wh battery with compatible 500 Wh versions easily available. The Pendix 500 is larger than their 300 Wh battery and therefore may not fit your frame (case for most Muli cargobikes).
• Gear choice and surveillance: much more comfortable and safe at thumb’s range, you can always see your remaining range which gives you a more precise idea of your consumption and avoids wasting capacity because of forgetting to switch back down.
• Charging cable: the Bosch charger can more easily disconnect from the battery because it is not magnetic. I guess that’s the downside of the advantage that this system does not attract magnetic dust.
• Availability: you can easily find Bosch service in most places, which I however never needed. There are now more and more touristic stations where you can charge Bosch even without bringing your charger, which for Pendix didn’t work the only time I tried, even though the station had the right cable. And if you ever forget to charge before leaving or overestimate your range, it can be pretty easy to find someone with a Bosch charger, like back in the Nokia days 🙂

Range comparison

Generally it seems Pendix is less efficient than Bosch. However I think that has technological as well as usability reasons: Bosch has more assistance levels, making it easier to choose an adequate mode. Then as described above, the Bosch computer always shows what mode you’re in and how much range remains, avoiding forgetting to reduce assistance level and making surveillance of consumption very easy without having a Bluetooth app using your phone’s screen as in the case of Pendix. And reaching down to the Pendix battery is simply cumbersome, so it’s quite attractive to just stay in medium mode, wasting capacity. However you can customize assistance levels in the Pendix app so as to stop assisting at low speeds or adapting the torque in each mode to optimize efficiency.