The Specialized SL 1.1 E-road bike motor is the youngest model in our test. According to Specialized, developing this system has been its largest investment to date. Has all the effort been worth it?

For an overview of the test fleet head to the main article: The best E-road bike motor – The 5 most important E-road bike motors on test

The SL 1.1 system offers 35 Nm torque and a maximum assistance level of 100%, doubling your input in Turbo mode. That means that the mid motor drive from the American brand has similar specs to the 40 Nm torque and 100% support of the Ebikemotion hub motor, but the similarities end there! The battery of the SL 1.1 system is fixed in the down tube and has a capacity of 320 Wh. If required it can be removed or replaced by a Specialized dealer for servicing. Specialized also offer a range-extender battery with 160 Wh capacity, which can be mounted in your bottle cage. This system is adaptable, allowing the additional battery to either charge the main one, be used simultaneously, or even independently without the main battery at all.

The Specialized motor reacts quickly whilst accelerating and engages quickly. The engagement angle of the cranks before the motor delivers its power is on the same level as both the Bosch and Shimano concepts. In Eco and Sport modes the drive stays subtle while delivering enough power to propel you onwards a little quicker. This is where the motor reveals that it’s designed for sportier riders who want to have the opportunity to embrace the effort of a traditional road bike on their E-road bike as well. In Turbo mode the system develops enough power to propel you up mountain passes even with tired legs. However, whichever mode you’re in, 0% effort from you means you’ll get 0% back from the motor. The wide power band of the SL 1.1 was a particular highlight for our testers! The system is capable of delivering its full power in a cadence range from 70 to 110 rpm and exhibits a significantly wider range than the other motors on test. Indeed, in part, these only feel completely happy in a narrow 10–15 rpm range.

Similarly, the transition of the SL 1.1 at the 25 km/h assistance limit is without equal. Even the e-veterans of our E-MOUNTAINBIKE team all agreed: the transition from supported to muscle powered riding is the best implemented that we have ever experienced. The transition feels natural like no other system in the test.

In terms of noise, the Specialized motor is similar to the Shimano motor and depending on the assistance mode, does make itself heard every now and again. In comparison with the Shimano STEPS E8000 the larger Q-factor is noticeable here. The 181 mm of the Specialized system is a whole 6 mm wider. For existing road bikers who want to ride the SL 1.1 system, that could end up being a bit of a turn off.

In terms of integration and operation, the Specialize motor is unique. The exclusive drive is currently only available for Specialized’s E-road bike. That allows the US brand to design motor and frame concepts down to the finest detail and integrate the system without any compromises. In turn, the Specialized Mission Control app, the Turbo Connect unit in the top tube and the Turbo Connect display make up a closed and coherent ecosystem. The app offers multiple functions such as tuning assistance modes, calculating range and tracking routes. Unfortunately, to change assistance modes, you have to take your hand off the bars to get to the top tube. It remains to be seen if and when Shimano will open up its Di2 shifters for third parties and in turn make tidy, intuitive and above all safer options available for all manufacturers.


The Specialized SL 1.1 system is without a doubt the most natural riding motor in our group test! The seamless transition at 25 km/h and the wide cadence range aren’t matched anywhere else. If we had to crown a winner, it would probably have to be this motor! However, the wide Q-factor and the fact that you have to remove your hands from the bars to operate the system can’t be ignored. Despite this, the SL 1.1 comes highly recommended and is our top tip – no other drive offers the same natural road bike feeling!

Torque 35 Nm
Motor weight 1.82 kg
Support modes 2
App control Yes


  • International service network
  • Smooth transition at 25 km/h
  • Operation and layout of the Kiox display


  • Heavy
  • Large Q-factor

For more info head to:

For an overview of the test fleet head to the main article: The best E-road bike motor – The 5 most important E-road bike motors on test

All motors in test: Bosch Active Line Plus | Ebikemotion X35 M1 | FAZUA Evation | Shimano STEPS E8000

This article is from GRAN FONDO issue #012

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Words: Benjamin Topf, Felix Stix Photos: Robin Schmitt