Radio Sonar Free Coaster Hub – finally, a Free Coaster that works for MTB.

Most freecoasters are heavy, fragile, and a nightmare to maintain. The Sonar flips that script: built on a cassette-style system, it’s lighter, tougher, and way easier to live with. The MagnaDrive magnetic pawls keep things running smooth without springs giving up, and the oversized adjustable slack makes it feel natural both ways.

At 33% lighter than most freecoasters and rolling with zero drag, it’s one of the fastest hubs out there—forward or fakie. After 4 years of testing with Niklas Tilk, Radio dropped a hub that actually makes sense for mountain biking: 135mm spacing, disc mount, 10t or 12t driver.

SONAR Free Coaster HUBSPECS

MATERIAL • 6061-T6 Alloy hub shell & 7075-T6 axle, stainless bolts
SIZE • 135mm x 10mm, 32h
BEARINGS • x5 sealed high-grade stainless bearings
DRIVER • 10t 1pc or 12t cog (mini hg) driver
COLOUR • black & nebula purple
DIMENSIONS • PCD (DISC) 58mm, PCD (R) 58mm, Flange Spacing 67.75mm, Flange Offset (DISC) 32.21mm, Flange Offset (DRIVE) 35.54mm

FEATURES

MTB specific Free Coaster hub with 135mm spacing
First hub of its kind in MTB, exclusive to Radio Bikes
Super lightweight hub using Wethepeople patented “HYBRID SYSTEM” Internals
adjustable gap / slack
Zero drag system makes it one of the fastest hubs out
“MagnaDrive” Magnetic pawl retention system
Easily convertible into a cassette hub (all parts incl.)
10t one-piece driver or Mini HG cog driver (inc. 12t cog)
6 bolt-disc mount
33% lighter than a conventional clutch style Free Coaster hub
Incredibly durable and maintenance-free system

WEIGHT

• 457g / 16.1oz (12t)
• 442g / 15.6oz (10t)