Testing the Rimpact Chain Damper

Jono here, I’m the owner of Outspoken Cycles.

I’ve ridden bikes for a fairly long time. It's been 22 years since I started riding at 12 years old, and I've done a fair few laps over that time. Also during that time, we've seen Mountain Bikes change dramatically. Disc brakes, wide bars, functional suspension, dropper posts, narrow-wide chainrings, sensible frame geometries and a bunch of other genuinely useful upgrades. As a keen rider, it's been a treat. 

But for every real upgrade, there have been numerous other product releases that fell flat, often just marketing fluff. So whenever I hear some new industry hype, I tend to file it under “review later when the dust has settled.” One such hype product was the O-chain, released in 2022. It’s an “active spider” that decouples your crank and drivetrain engagement, creating free float between chainring and cranks while you’re not pedalling. In theory, this reduces the effects of pedal kickback.

I was recently reminded of the O-chain in late 2024 when Rimpact released a competitor product: the Chain Damper. I’ve talked to Matt (founder of Rimpact) enough over the years to know his products aren’t hype-driven. I figured it was time to dig in and see what it's all about.

So what’s pedal kickback?

When your rear suspension compresses, the axle moves slightly away from the bottom bracket, which also pulls the cassette away from the chainring. Since the two are locked together by the chain — which won’t stretch or break — the only way to take up that extra distance is for your cranks to rotate backwards. In short: when the suspension compresses, your pedals get forced backwards. That’s pedal kickback.

When you're descending on the trail, you're almost always standing with most of your body weight on the pedals.  Each time the suspension compresses, your cranks try to rotate back and your front pedal gets shoved up into your foot. It sounds minor, but with most of your weight there the force is significant — and you can’t help but resist it. That resistance appears as harshness to you as a rider. It also pushes back against the suspension itself, making it less free to move through its travel. 

So yes, pedal kickback is real. But is it actually a big enough problem to matter? Is it a 1% hit to performance and comfort, or closer to 20%? And in a sport where we willingly hurl ourselves down rooty, rocky trails, is a little extra harshness even worth worrying about?

So as the Lead Outspoken Test Monkey (🫡), I figured I’d better find out what this was all about. Early in 2025 I picked up a Rimpact Chain Damper ($600 RRP) and bolted it on.

That's an expensive chainring 😅

Rimpact Chain Damper - First Impressions 

Installation was easy. Pop the cranks off, swap the chainring for the damper, and you’re done. The first pedal stroke was… Odd… Mushy and then solid… This will be interesting.

Yummy! 

The carpark test felt bizarre. Mush mush. Righto, lets go to the Christchurch Adventure Park and get into it. First lap time: Summit Connector and Choir Boy — trails that usually rattle you to bits.

How did they feel? Instantly smoother… 

Seven laps later, and I'd ended my day. Here’s what I wrote in my testing journal:

“Feet hurt less than usual. Bike was less noisy and seems smoother everywhere. Don't have good words for it yet but either way, I'm a fan.”

A promising start!

6 months of riding

Fast forward half a year, and I’m a big fan. In fact, my fannage has made this section quite tricky to write. It's been concerningly easy to slip into a stream of glowing adjectives that sound like the marketing fluff I’m so allergic to. So if any of this comes across as fluff, please chalk it up to my writing, not the product.

I’ve found the Chain Damper to genuinely change the feel of my bike. Here’s what I’ve found:

The bad: Climbing & traversing

Pedalling does feel different. The first stroke is vague until the device fully engages, and if you don’t keep a bit of pressure through the rotation it can disengage mid-stroke. That happened to me early on, but with a small tweak to my technique — just keeping light pressure through the circle — the issue disappeared.

On steady climbs I barely notice it. The problem shows up on technical uphill features, where I’ll often slow down, pause, and then try to explode up and over the feature. In those moments the Chain Damper can disengage, and when I stomp on the crank there’s a noticeable delay before it catches again. Sometimes that little gap is enough to blow it and forces me to dismount.

If you live for cleaning every tricky climb, that’s going to frustrate you. For me, I climb so I can descend — so while it’s a flaw, it’s not a dealbreaker.

The good: Descending

Have you ever done downhill laps without a chain? If so, you’ll know how the bike suddenly feels calmer and less harsh. Well that’s what the Chain Damper makes your bike feel like, except you still have the chain. Here’s what I’ve found when descending on the Chain Damper:

Small trail chatter: Trail buzz feels muted. The only way I could describe it to a mate was “it’s just more buttery.”

Medium hits: Rocks, roots, braking bumps — the suspension feels easier to get moving, with a smoother ‘on-ramp’ into the travel.

Big hits: Same story, just more obvious. It’s like the suspension is getting started quicker and that somehow makes bottom-outs also feel less harsh.

General stability: When things get rowdy, the bike feels calmer and easier to keep on line.

Traction: On sketchy off-camber corners I’ve been able to hold some lines that used to spit me off.

Noise: It’s quieter…

Acceleration: riding buddies have even commented that its got harder to keep speed with me, despite me putting in no extra effort.

Comfort and Fatigue: My flat feet usually cry uncle after a full day of laps. With the damper, they last longer — enough that I can do an extra lap or two.

For me, the Chain Damper is a clear win. I’m more comfortable, slightly faster, and having more fun. If your riding is all about descents, I suspect you’ll feel the same.

Is it worth $600? For me it’s worth the ~10% premium on my bike to make descending notably more enjoyable. But if climbing performance is your focus, I’d give it a miss.

Want to learn more?

Send me a message on our contact form. I'd be happy to jump on a call to discuss my experiences with you. 

And if you've got half an hour to spare, here's a video by Remy Metailleur about his experiences running the Chain Damper: