We’ve seen a number of devices add dampers into your drivetrain to combat pedal kickback for smoother, more supple suspension, but Rimpact’s new Chain Damper puts it directly inside a special chainring sandwich. Promising stiffness, all weather durability & a ” “incredibly stiff and “creak-free” design, the Chain Damper uses its own proprietary chainrings, but a classic direct mount crank arm interface to make it easy to fit to your bike…
Rimpact direct mount MTB Chain Damper and chainring
Yes, we know Rimpact for their foam tire inserts that prevent rim impacts, so what are they doing with a mountain bike chainring that damps chain slap?
Well, they’ve now engineered a new gadget that they claim will ‘momentarily’ capture the energy from your bouncing chain and smooth it out over time (damping) to quiet drivetrain feedback on your bike, both figuratively and literally. Smoothing those spikes in tension, Rimpact says their Chain Damper delivers “a silent and calmed ride characteristic that lets the rider focus in on subtle suspension movements and the sound of tyres[sic] gripping the dirt“.
So you get smoother suspension and a quieter ride? What more could a mountain biker ask for?
Why do you want or need to damp your chain in the first place?
Simply put, on most full suspension bikes, as the bike moves through its travel chain length changes – most often increasing. So as you stand on your pedals, the tension in the chain between your chainring and cassette keeps the bike’s suspension from moving smoothly. By detaching your chainring from your feet slightly, the chainring can rock back and forth when you are standing flat on the pedals descending through rough sections, allowing smoother suspension action. The same effect is there to a lesser extent when pedaling through chunky sections of trail, as well.
Also, as you quickly hit sharp-edged bumps your chain simply bounces around above and below your chainstay. It’s the reason we modern mountain bikers all ride clutched derailleurs these days. But that can really only be managed on the bottom loop of the chain between the derailleur & chainring. So Rimpact’s Chain Damper chainring will damp that movement on the top of the chain, preventing chainslap, and seriously quieting your ride.
“A chain weighs around 260 grams on average and the top part of your chain, (the length between the chain ring and cassette) can move at 8 meters per second, completely uncontrolled. Clutch derailleurs offer some amount of control to the lower part of your chain but the top remains free to flail wildly.
Here at Rimpact, we think the significant effect of this uncontrolled chain energy plays a bigger part in unwanted ride characteristics than other sources of negative drivetrain feedback.”
A damped chainring means a smoother feel, better rear wheel grip on the ground, and a quieter ride in the end, too.
Tech details
- direct mount compatible with Shimano MTB, SRAM 3-bolt X-Sync & SRAM T-Type 8-Bolt crankarms
- CNC-machined 7075-T6 hard anodized narrow-wide chainrings available in 30, 32, 43 & 36T sizes
- 11 & 12-speed compatible, including SRAM T-type compatibility
- 2 stiff internal springs capture and return the energy from your chain
- 2 internal elastomers limit rotation to +/-5° and damp the energy return
- 1 main IGUS bushing handles rotation and 4 thrust bushings handle alignment between the chainring & Chain Damper spider
- 2 X-ring seals between the fixed spider and rotating chainring keep water & dirt out, and are “designed to survive UK winters“
- total system weight 230g (140g for the Chain Damper spider, plus 82g for the 32T chainring with its bushing. Yes, we also noticed that those numbers don’t add up.)
- replacement chainrings and service kits are also available
Rimpact Chain Damper – Pricing, options & availability
These new Rimpact direct mount MTB Chain Damper and chainring complete setups are available now for £280 / $375 / 325€, ready to bolt directly to most Shimano and SRAM direct mount mountain bike crank arms, as well as others that share those same standards. Rimpact says they have RaceFace, e*Thirteen, Hope, and various eMTB versions in the works, but are gauging interest before putting those into production.
When you buy a complete Chain Damper, Rimpact lets you pick a 30-36T chainring. But those special proprietary rings are also available as separate replacements for £70. There’s also a £25 service kit that includes the elastomers, bushings, and seal rings that will wear out over time, but are all super quick and easy to replace.
Everything is available now direct from Rimpact online – well, 32 & 36T rings in stock today – or through their international distributors very soon.
