E-bike knowledge: What range can a Bosch motor achieve at which speed level?

Researchers dream of a perpetual motion machine, a drive that keeps on running without any energy input. E-mountain bikers definitely do too. In practice, however, they tend to have a nightmare in mind: Will my e-bike battery last for the tour? Will I make it to the next summit? The sceptical glance at the battery level indicator is a constant companion for e-bikers. We did the test and pedalled uphill on a bike with a Bosch motor in all four support levels (Eco/Tour/Sport/Turbo) until the battery ran out.

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The question was: How much is the benefit of switching between support levels? How much does the range increase? How much does the speed decrease? What about your own power reserves?

Of course, we always travelled the same route and used the same bike with the identical 400 Wh battery for all our rides. To ensure that the gear range was sufficient and the cruising speed did not drop to an unbearable snail's pace, we increased our own power in 10 watt increments per stage. In Turbo mode we only pedalled at 130 watts, in Eco mode at 160.

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What is the benefit of downshifting my e-bike motor?

Based on the support level, the e-mountain biker chooses how much support the motor provides. It's a tough choice: the less the e-bike drive delivers, the more you have to do yourself as a rider. But how much range do I really gain by downshifting my e-bike drive? The most important finding of our test: switching from the highest to the lowest setting doubles the range! However, everything else is also changing.

Speed and altitude change depending on the mode

The average gradient of our test route is 8.5 per cent. In the Turbo mode (stage 4), you literally fly towards the summit at 17.5 km/h, and after three quarters of an hour you have 1110 metres of altitude on the clock. No cross-country pro can keep up with that. In Sport mode, the battery is not spared as much as expected, with only 130 metres of altitude gain. At level 2 (Tour mode) it was already 415 metres more altitude. Only stage 1 (Eco mode) is really worth it: over 1000 metres more altitude. But the price is high! The travelling speed drops to a snail's pace: 8.8 km/h - just half that. And the level of exertion suddenly becomes comparable to a bike without an e-drive: if you can manage a little more than 200 watts instead of 160, you could even switch to a comparable, motorless bike. The only difference is that you won't be able to switch to a higher support mode on the next ramp.

Tip for more range: Only switch to turbo mode on steep ramps

The additional height achieved is mainly due to the driver, who delivers 4.6 times more power in Eco mode than in Turbo mode. It goes without saying that you drive further. But it also takes significantly more time and effort. Nevertheless, if you are reasonably fit and only select a high support level on the really steep ramps, you can also manage E-MTB tours of around 2000 metres in altitude with a 400 Wh battery.