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Stan’s NoTubes partners with Project321 for new M-Pulse magnetic hubs

Stan’s NoTubes has long been an innovator when it comes to tubeless wheels and rims. After all, the company’s mission has been baked right into its name since day one. Its reputation hasn’t been quite as impressive when it comes to hubs, though, but now NoTubes is looking to turn that ship around thanks to a partnership with widely regarded American boutique hub brand Project321.

The biggest change on the new M-Pulse hubs is a switch from a conventional leaf-spring driver mechanism (where the springs are pushing the pawls outward into the ratchet ring) to a magnetic one featuring six pairs of neodymium inserts — one pair for each pawl — with the magnets pulling the bits together. 

Instead of metal springs that push the pawls outward against the ratchet ring, the magnets in the M-Pulse hub pull them. Photo: Stan’s NoTubes.

According to NoTubes, this switch makes for a more positive and reliable engagement, which make sense given the nature of how push-type mechanical springs work as compared to pull-type magnets. Whereas the former exerts less force as the spring extends (such as when a mechanical freehub is engaged), magnets exhibit peak attractive force as the two halves get closer together. Further enhancing the rear hub action is the use of a 216-tooth ratchet ring and multi-tooth pawls, which bring the engagement speed to an ultra-quick 1.66°.

That reversed spring curve offers another claimed benefit, too. Since the magnetic attractive force falls off dramatically with increasing distance, the pawls don’t exert that much outward pressure against the ratchet ring teeth when you’re coasting, which NoTubes says reduces mechanical friction.

“[Project321 hubs] have been very reliable apart from a magnet that came unbonded in a pawl very early on, maybe five or six years ago,” said veteran wheelbuilder Zack Macik of Zspokes in Charlotte, Vermont. “They had already realized the issue by the time I had a problem and were using a different adhesive. They’re light, relatively quiet (significantly less noise than Industry Nine) and roll very smoothly.”

Other features include oversized 17 mm-diameter 7075 aluminum axles, fully shielded cartridge bearings throughout, a double-row main freehub bearing, and adjustable bearing preload front and rear. Spoke flanges are specifically sized so that the same spoke length can be used throughout each wheelset, and NoTubes is sticking with J-bend spokes for easier servicing.

All of the bearing cartridges come courtesy of Enduro, while the freehub body shells, magnetic pawls, ratchet rings, spacers, and axles are made for NoTubes by Project321 in Bend, Oregon. 

Adjustable bearing preload should not only help with bearing longevity, but also rolling friction.

All of these improvements sound quite substantial, and NoTubes also appears ready to stand by the durability of its new M-Pulse hubs with a five-year warranty.

NoTubes is featuring the new M-Pulse hubs on three aluminum mountain bike wheelsets — the 30 mm-wide Flow MK4, 28 mm-wide Arch MK4, and 25 mm-wide Crest MK4 — as well as all of its carbon fiber CB7 and Podium SRD models, including the gravel-focused Grail CB7. Prices start at US$965 for aluminum models, and US$1,987 for carbon ones (pricing for other regions is TBC).

More information can be found at www.notubes.com.

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