%age power???

[Exrm193]

Bosch Gen 3-4 motor. When in Eco mode. Does anyone know what percentage of assistance is given to you?? In Turbo, you presume 100% of available assistance is there....but what about eco mode??

 

[irie]

This might help.

eMTB Mode Explainer

Let's look at the different modes of assistance offered by three of the main motor players in Bosch, Shimano, and Specialized.

www.ambmag.com.au

 

[RustyIron]

Hey, @irie.
Thanks for the article, but it's from 2021. The current Bosch system is substantially different than what is described in the article. I have the same questions, but haven't seen the answers.

@Exrm193:
One might assume that Turbo Mode was pumping out maximum mojo. It would make sense. But the Flow App allows you to adjust various settings. If I increase all the settings for Turbo, does that mean that I'm overclocking the motor, or does it mean that the default settings are anemic?

 

[RustyIron]

Ok, I just read a little more, but the information is pretty vague. Just for the sake of discussion, the four modes for my bike are Eco, Tour+, EMTB, and Turbo. The default maximum torque for all these modes is 85nm.

The "Assistance" is the maximum percentage of power the motor will output in relation to your pedal input. For instance, if the assistance is 100%, your motor is pumping out the same amount of power you're putting in, effectively doubling your power to the wheel.

I'll spare you the lame graphics from the Bosch web page. Essentially, they're trying to tell us that the assistance level for Eco is 60%, Tour is 140%, Sport is 240%, and Turbo is 340%. If you have the Race motor, the Race mode pumps out 400%.

The Tour+ mode is "dynamic." It varies between Eco and Tour modes, or 60% to 140%. The EMTB mode is also "dynamic," varying between Tour and Turbo modes, or 140% to 340%.

 

[irie]

Hey, @irie.
Thanks for the article, but it's from 2021.

Which I think applies to "Bosch Gen 3-4 motors" which was referenced in the original post.

hth

 

[Mikerb]

The only change in the Gen 4 motor was the NM increase from 75nm to 85nm.

Firstly the amount of assistance from the motor in any mode is graduated ,not "on/off". To create a relatively natural feel the power from the motor is governed by crank cadence and rider torque.

• Most brands refer to their motor putput as " X times You" ( where you is the rider of course!). The issue here is however that the power of for example a young very fit rider is not the same as for a more "average" recreational rider! They must therefore use a figure they feel representative...but we do not know what that is!!
• Regardless what that rider output figure is that they use, the motor obviously has a maximum power output.
• The motor also has power torque curve in accordance with cadence........so for example the Bosch Gen 4 maxes out at a bout 80 rpm.

So taking into account all of those variables I think the best way to consider the assistance level for each mode is merely as a comparison.
Turbo is c 5.56 more assistance than ECO and c 2.45 more assistance than Tour.

Because the software designer created rider profiles using both cadence and torque sensor inputs as an algorithm, what a rider a ctually experiences in each of the modes may differ; for example if greater motor assist is programmed at lower cadence and/or lower rider torque that may "feel" more powerful than if the reverse was the case.

All of which is why getting familiar with the characteristics of any brand of motor is what delivers the best results.