Syntace, Liteville and Canyon are jointly launching a concept they call KIS (Keep It Stable), which uses a spring to “stabilize” the steering of the bike by applying a carefully designed force that acts to pull the front wheel toward the straight-ahead position. This is designed to counter a force called wheel flop, which acts to push the steering away from center. We’ve all experienced this on a slack bike at low speeds, where the handlebars feel like they’re steering on their own away from straight, resulting in erratic steering. The system also claims to make the steering less jittery, more weighted and more predictable.
How it works?
One thing to clarify is that this is not a steering damper. These have been tried before and generally don’t seem appropriate for mountain bikes, where gears are slow and quick changes of direction are required. This is a steering spring, which exerts a torque on the steering assembly (the front wheel, the fork and the cockpit) which depends on the steering angle – the angle of the front wheel in relation to the straight ahead position. The farther the steering assembly is from the right front, the more spring force (torque) acts to return it to center.
It does this with a pair of small springs anchored in the top tube, which connect to the fork steerer via a pair of kevlar strips connected to a cam wheel clamped onto the steerer tube. When the bars are turned to one side, the springs are stretched, creating a force in the opposite direction. The geometry of the kevlar bands and cam are designed to give the torque curve below, where the breakout torque increases rapidly as the steering angle moves away from a straight line around about 15 degrees and then increases more gradually to make it easier to negotiate tight turns without feeling restricted.
This torque is designed to counteract the force created by a phenomenon called wheel flop. If you stand your bike upright with the steering off center, the handlebars will naturally angle away from the front towards a 90 degree steering angle. This is because as the steering angle increases, the bike frame (and with it the rider) lowers towards the ground – by more than 10mm in the case of a slack bike.
To illustrate this, imagine a bike with a 0 degree head angle (a horizontal fork). Now when you turn the handlebars away from straight through 90 degrees, the steerer tube would drop to the ground through the spoke of the wheel. With a vertical head angle, the head tube would not drop at all. So, the lower the steering angle of the bike, the more the head tube will dive when the bike steers.
This drop in head tube height creates a force that acts to push the steering away from straight ahead. This is a destabilizing force because (in the range of normal steering angles) the further the steering moves away from the straight line, the more the force acts to push it even further away.
The KIS system is designed to compensate for this, making the steering assembly more stable and less prone to pulling to one side.
Much like a trailer towed behind a car, the contact patch is effectively towed behind the steering axis, causing it to naturally line up behind it. This creates a self-centering force that counteracts wheel flop force and overcomes it at higher speeds. This is why the view on loose bikes seems stable at high speeds but unstable “wandering” at low speeds. The effect of the KIS system is to provide additional centering force that works at all speeds, making the steering less unstable at low speeds and even more stable at high speeds.
Wheel rocking force depends on the amount of weight on the front wheel, so the system offers an adjustment mechanism to tailor the amount of counterforce it provides based on rider weight and preference. personal. This is done with a slider that changes the preload on the springs.
In practical terms, Canyon’s system weighs 110g and Liteville slightly less. It’s maintenance-free and uses a regular fork that can be removed or replaced by unscrewing the cam bolt, which in the Canyon’s case is accessed through a port on the left side of the frame. At the front of the steerer tube is a set screw that prevents the cam ring from rotating beyond 90 degrees. If the handlebar is forced beyond this angle (during a collision, for example), the cam ring will slip on the pivot. When this happens, the system must be reset (like straightening a rod) or else the mechanism will pull the steering to one side.
For now, Canyon is releasing only one model with the KIS system, the Spectral CF 8. Canyon says they chose this model because it’s their best-selling bike and they wanted it to be available for the biggest number of buyers. The system has been tested on downhill bikes and was even used at the Fort William World Cup under Mark Wallace, but only in practice. Canyon announces plans to “deploy KIS to many more models in the future.” Liteville has an electric bike with integrated KIS: the 301 CE EMTB.
The standard Spectral CF 8 is priced at £4599 (4599 EUR) and the KIS equipped bike is £4999 (4999 EUR). It’s due to land in the US in the spring of 2023. You can’t adapt the KIS to another bike, but the system can be removed and blanking plates will be available next year.
Journey impressions
I got to try the system with a day of heave-assist riding on the Canyon Spectral, followed by a ride on the Liteville 301 eMTB the next day.
The first thing I did was carve some turns in the parking lot. Although it seems strange at first, it is very easy to adapt to the system in this case. But riding without hands on the bars is very difficult. Normally, when you lean to the left without touching the bar, the steering assembly spins to the left due to a combination of its own weight, wheel flop, and gyroscopic forces, and this steering causes the wheels to roll back below the cyclist’s center of gravity, correct the lean and keep yourself straight. But with KIS, the steering stays closer to a straight line, so the bike tends to fall over (called capsize). So while the steering may be more stable in terms of self-centering, it does not necessarily make the bike more stable in the sense of standing.
But what about on the trail?
Again, it’s easy to adapt to the system as a whole, but there were times when something seemed a little odd. I found myself running wide in corners at times, especially with the system tension turned to max. It’s not that I couldn’t turn the steering to the angle I needed to make the turn (the force is pretty modest), but the subtle counter-steering needed to initiate a turn needed recalibration. To turn left, you must first steer to the right (counter-steer) so that the bike is unbalanced and leans to the left; only then can you steer the bike to the left without falling. I think with KIS engaged (especially at max setting) I wasn’t counter-steering enough and therefore not leaning enough, so I had to brake into the corner or adjust my steering mid-corner to get around.
Of course, it’s something you get used to the more you drive it, but when I switched between the system’s maximum, medium and minimum torque settings on the Spectral, I always preferred the minimum setting. I found it easier to make tight turns and stay balanced. Even on rocky high-speed straights, where I expected the bike to feel safer and easier to handle with KIS, I sometimes found my weight in the wrong place and felt slightly less balanced with the maximum preload. I think the constant micro-corrections needed to maintain balance have been toned down, making it a little harder to feel balanced above the balance point.
Similarly, on the LIteville eMTB, I rode hard corners and shoal-cut tight trails and felt less able to correct and stay perfectly balanced with the system on versus off (the Liteville demonstrator could be completely off). When I got to exposed switchbacks near the end of the ride, I kept the system off because it felt safer.
Don’t get me wrong, the downsides are subtle and easily overcome with practice. There are also pros in that the steering feels more weighted and stable, especially on low speed uphill switchbacks where there is less wheel flop, but I noticed the cons more than the pros . Jo said it takes a long time to fully get used to the system and I’m sure with more time I would adapt to the different forces required at the handlebars to ride smoothly. But the dilemma with testing any new technology is that once you get used to it, you’re not used to riding anything else. For example, I once cycled for a week on a road bike with heavy panniers; when I took them off I remember the bike feeling awfully jittery for the first minute or so. That’s not to say the handling with the baskets was better, just that I preferred what I had grown accustomed to.
And while the system reduces the rider intervention required in certain situations, like tight, slow switchbacks, it takes more effort to stay balanced at high speeds or throw the bike through tight turns. I’m sure if I had ridden with KIS for a long time (months or years), a bike without it would feel weird. But it’s not clear to me that the system makes the bike easier to handle, as opposed to just different.
Fabien Barel described the system connecting the front and rear of the bike, making it easier to correct front wheel drifts. He might be right, and it will be interesting to see if any Canyon athletes use it for racing next season. But from my (brief) time on the KIS system, the benefit is hard to discern.
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