Sea Otter: Kappius’ magnetic hubs and carbon rims

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240 points of engagement are just the beginning

Magnets, how do they work?
Magnets, how do they work?

Introduced at Sea Otter two years ago, Kappius Components’ KH1 hub puts the space behind SRAM Powerdome cassettes to use in order to improve axle support and make space for a massive, magnetically-driven freehub.  The company’s conical freehub body- available in 1, 10, and 11-speed versions – houses a large bearing and 60-tooth ring.  The ring drives the hub via a series of eight pawls, clocked to engage in pairs, making for remarkable 240 points of engagement.  The pawls themselves each house a small rare earth magnet, working to repel an opposite in the shell- the configuration doing away with the need for springs.

Vented shells make for happy bearings.
Vented shells make for happy bearings.

Happily, the interesting doesn’t stop at the freehub.  Kappius’ carbon fibre and alloy hub shell is vented to prevent pressure buildup when braking.  This keeps water and muck from being drawn into the bearings when the hub cools.  The two-stage finish is the result of an initial anodisation followed by surface machining and a corrosion-resistant alodyne coating on exposed surfaces.  Why?  Because it looks cool.

Machining of your XX1 cassette is included.
Machining of your XX1 cassette is included.

Entirely machined in the US, the complete KH1 hub weighs approximately 300g and will relieve the pocketbook of $700 (£420), including the machining of the customer’s X0 or XX1 cassette to fit.  A matching front hub sells for $300 (£180).

That's the freehub body in there.
That’s the freehub body in there.

For anyone looking to run an unmodified cassette, the KH1.5 moves the bearings and freehub mechanism to their more common location under the drive-side hub flange and removes the vents.  The simpler rear hub sells for $500 (£300) and its mate $250 (£150).  An all-alloy KH2 set is expected soon at $430 (£255) and $220 (£130).

Tubeless-compatible trail rim
Tubeless-compatible trail rim

Moving away from CNC-machined parts, the KR-29 rim is Kappius’ first rim offering- one eight months in the making.  Measuring 30/26.4mm across, the 29er rim is designed for cross-country and trail use. Designed with tubeless tyres in mind, the rim has a shallow centre channel to make inflation easy, even with a hand pump.  The mild hooks and slight ramp down toward the bead should keep low-pressure rubber in place nicely.

A 355g weight puts the 29er rims at the low end of the weight spectrum for their intended use.  The Kappius-exclusive KR-29 retails for $600 (£360).

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Comments (4)

    A “pressure build up when braking”…….. yeah, right, if you say so #morewinningmarketingbull

    o> salutes the Insane Clown Posse reference.


    Thanks- though the credit belongs to ICP for – unintentionally – making what may be the most amazing song/video ever.

    Marc B

    “This keeps water and muck from being drawn into the bearings when the hub cools”

    And yet there’s a load of dirty great holes in the middle of the hub that’ll let dirt and water in that you won’t be able to reach. Sounds like a great solution to a problem I didn’t know I had.

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