To keep the weight in check, both bikes have full carbon frames and the batteries are integrated into the down tubes
The lightweight, lower-powered e-bike category is easily the fastest growing sector in mountain biking right now. And while everyone is clambering to get on board, two brands that are way out in front of the latest trend are Specialized and Forestal. Not only do both have lightweight, lowerpowered trail bikes, they also have sub-20kg, 170mm-travel 29er e-enduro bikes. Forestal has the Siryon with a 60Nm motor and 360Wh battery, while Specialized delivers the Kenevo SL with a 35Nm motor and 320Wh battery.
To keep the weight in check, both bikes have full carbon frames and the batteries are integrated into the down tubes. That doesn’t mean that they can’t be removed or replaced, you just have to take the motor off to do it.
And if the thought of having such a small fuel tank makes you nervous, range extenders are available aftermarket from both brands.
But what makes a lightweight lower-powered e-bike feel so different to a normal e-bike?
Well, obviously there’s the reduced weight – the S-works Kenevo SL tips the scales at 18.79kg, the Forestal Siryon at 19.8kg. But that can’t be the full story, as the full-powered Canyon Spectral ON CFR weighs 22.8kg with a massive 900Wh battery fitted and still feels pretty agile. So what gives?
We think there are two things at play here and both have to do with the smaller battery capacity. By limiting the battery size, you don’t need an oversized down tube in which to hide it. All other things being equal, increasing the diameter of the down tube increases the overall stiffness of the bike. So with mid and lowpowered e-bikes, the proportions of the frame tubes more closely mirror those of analogue bikes, so the flex response follows suit.
Smaller batteries are also shorter, so the weight of the battery is closer to the centre of gravity of the bike. Which in turn reduces the inertia, especially around the steering assembly. So the lower-powered bikes change direction more easily, which again makes the handling of the Specialized and Forestal feel more akin to a regular enduro bike.
The reduced drag of the motor can’t be ignored either, especially when riding trails where you need to pedal above the 15.5mph assistance limit. This is most noticeable on singletrack, where you need to sprint to clear a feature, or simply want to go as fast as humanly possible. Neither bike has zero motor drag though, but the ease with which the Specialized and Forestal pedal when the motor cuts out definitely makes it worth your while to keep spinning the pedals.
One less obvious similarity between our two test bikes and analogue enduro bikes, is that you change gear way more frequently than on a full power e-bike because you can’t soft pedal and expect the motor to do most of the work for you.
Also, not all lower-powered e-bikes are created equally. The motor on the Specialized only has 35Nm torque, so typically 50Nm less than a full-powered e-bike. Now contrast that with the Forestal, which has 60Nm. That’s a big difference, and it’s why we’ve called the Specialized low-power and the Forestal mid-power. Which approach is best remains to be seen, but given that both bikes have jawdropping price tags, carbon wheels, and use SRAM wireless AXS drivetrains and Rockshox Reverb AXS droppers, both are evenly matched, at least on paper. They are also currently the only two bikes in this segment, which makes this an obvious head-to-head test.