Ever since the first multi-gear drivetrain was added to early mountain bikes, riders have been looking for a way to quiet chain slap and protect their frames. This pursuit gave rise to a cottage industry creating everything from neoprene wraps, to modern injection molded rubber guards as well as home-brew solutions including wraps utilizing bar tape and old inner tubes.

Like many aspects of cycling product design, 3D printing has opened up a new era of tinkering allowing potential companies to quickly prototype new ideas – like adding a magnet to your chainstay guard to attract the chain and prevent noise. That’s exactly what rali has done with their Chain Mag system, and it’s a fascinating take on the typical chainstay guard.

(All Photos/rali) Play

In addition to rubberized ‘fingers’ that act to dampen chain noise under most circumstances, the Chain Mag has a small block that houses a magnet just behind the chainring. The idea here is that when coasting, the chain will be attracted to the magnet, which holds it in place and doesn’t allow it to rattle around and make noise. It also claims to improve chain retention and reduce vibrations.

As soon as you start pedaling, the pedal force pulls the chain off the magnet and allows for pedaling without any additional friction.

In order for the system to work on different bikes with varying distances from the chainstay to the chain, rail sells five different sizes of the Chain Mag. You’ll need to use their sizing calculator to figure out which size you’ll need for your bike, or utilize their known bike fitment table if your bike has already been catalogued. Hoping to get more bikes added to the catalog, rail will give you a code for 36% off if you measure your bike and send the results.

In order to use the Chain Mag, you must first remove the factory chain stay guard on your bike. Then follow the instructions to cut the Chain Mag to size, and install it with the included 3M VHB tape.

Highlights:

• Drastically reduces noise, unwanted chain movement, vibration and improves chain security.
• Protects frame from unwanted damage from chain. 
• Zero friction while pedaling; pedaling forces always pull chain off the magnet. 
• Light weight at ~66 grams for the low variant, ~88 grams for the medium/tall variant (untrimmed)
• Super strong neodymium magnet in thin rubberized casing.
• Soft rubberized fingers designed to further dampen chain slap.
• One-piece chainstay protection with double-sided 3M extra strong tape.
• Trim to fit each chainstay length.
• Mountain bike, e-bike and gravel bike compatible.
• See tab for further fitment and sizing details.
• Installs in minutes and all you need is a pair of scissors.
• Tested to withstand hundreds (if not thousands) of rides
• Patent pending.

The Chain Mag sells for $32.95 plus shipping, though the brand is currently running a 30% opening discount on the site. Available now.

ralibike.com