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Stan’s Introduces New Hubs and Flow, Arch and Crest Alloy Rims

It's nice to see alloy rims getting the respect they deserve

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There’s always been something about Stan’s alloy rims and wheels that’s seemed a little … boring. But not in a bad way. I mean it in the same way that a good accountant, a good surgeon or a good pilot is boring. They don’t take crazy risks, they don’t rock the boat, they just do their job and do it well. Stan’s rims don’t push any narrative about front- or rear-specific spoke tension. There’s no bumps or contours or special upside-down spoke nipples. They’re just rims. And they’re good. And the hubs are similarly vanilla. There’s been no brag-worthy engagement numbers. No mechanism that makes them especially loud, or especially quiet. They’re just hubs. And they’re … good enough. But from now on, the most popular alloy rims and wheels in the Stan’s lineup, Crest, Arch and Flow, are going to be a little more exciting, and the hubs that Stan’s laces them to are getting a revamp in order to keep up. 

About five years ago, the Flow, Arch and Crest rims were divided into two categories: A lighter flagship model called the MK3 available as either a bare rim or as a complete wheel, and a burlier, heavier but more affordable model available only as a wheel called the S1. Today, they are being updated to the MK4 and S2 respectively. Pricing is the same throughout all three categories, with all of the S2 wheelsets going for $595, all of the MK4 rims going for $129, and all of the MK4 wheelsets going for a price they have yet to release. On that note, the hubs used on the MK4 wheelsets are also getting a complete revamp and rebuild, though details are scarce on that too at the moment. The new hubs on the S2 wheels are also brand new, which we’ll get to later.

All three rims share slightly different applications of today’s updates. Let’s start with the Flow.


Flow MK4 Rim
  • Rim Weight: 487g (27.5″) / 521g (29″)
  • Wheelset Weight: 1792g (27.5″) / 1882g (29″)
  • Front Wheel Weight: 820g (27.5″) / 1017g (29″)
  • Rear Wheel Weight: 1792g (27.5″) / 1882g (29″)

The new Flow MK4 rims and wheels are taking cues from the recently introduced Flow CB7 carbon rims and wheels. It got a tad wider and a tad taller, going from a 29.0mm internal width and 16.1mm height to 30.0mm internal width and 18.9mm height. But most importantly, the alloy Flow MK4 is now asymmetric, with a 3-millimeter offset drilling pattern. The goal is more even spoke tension thanks to the wheel needing less “dish” to center the tire over the hub. And as a bonus, the Stan’s Flow MK4 wheelset uses the same length spoke, left and right, front and rear. Despite the benefits of going asymmetric, it was a leap Stan’s had been avoiding in its alloy rims because asymmetric rims tend to be easier to damage on one side than the other. But also, the concept tends to lead to inconsistent sealing performance between the drive-side and non-drive-side beads because one “shelf” can be wider than the other. But the new Flow (as well as Arch and Crest) features a second dip alongside the one that runs just above the spokes that makes the seating footprint identical on both sides of the rims. This will help a tire rest more neutrally and evenly, helping prevent excess slack that will keep the beads from seating in those crucial first moments of adding pressure. The rim still features a welded seam, and are still made of lightweight 6069 aluminum. But if lightweight isn’t that big a deal for you, there’s the S2.

Flow S2 Rim
  • Rim Weight: 547g (27.5″) / 583g (29″)
  • Wheelset Weight: 2056g (27.5″) / 2156g (29″)
  • Front Wheel Weight: 950g (27.5″) / 1000g (29″)
  • Rear Wheel Weight: 1106g (27.5″) / 1156g (29″)

The Flow S2 rim stays symmetrical, but gets a boost in size. It went from 29.0mm internal width and 17.6mm height to 30.0mm internal width and 18.2mm height. It’s still built with eyeleted spoke holes and 6061 aluminum, making it about 60 grams heavier (29-inch) than the MK4 rim. But like its predecessor, the S1, the S2 is still available only as a complete wheel. The Flow S2 wheels are aimed at the same gravity-oriented riders that the MK4 wheels are, but at a lower pricepoint. They’re also well suited for the e-bike market, which is reflected in the updates made to the hubs specced on the S2 wheelsets, but we’ll get to that later.


Arch MK4 Rim
  • Rim Weight: 451g (27.5″) / 481g (29″)
  • Wheelset Weight: 1698g (27.5″) / 1782g (29″)
  • Front Wheel Weight: 773g (27.5″) / 815g (29″)
  • Rear Wheel Weight: 925g (27.5″) / 967g (29″)

The Arch is the more trail-oriented offering in the Stan’s lineup, and the MK4 got similar updates to the Flow, including the asymmetric profile and larger overall shape. Instead of a 26.0mm internal width and 16.0mm height, it went to 28.0mm internal width and 18.9mm height.


Arch S2 Rim
  • Rim Weight: 487g (27.5″) / 520g (29″)
  • Wheelset Weight: 1936g (27.5″) / 2030g (29″)
  • Front Wheel Weight: 890g (27.5″) / 937g (29″)
  • Rear Wheel Weight: 1046g (27.5″) / 1093g (29″)

The lower-priced Arch S2 went from 26.0mm wide and 17.3mm tall to 28.0mm wide and 18.1mm tall.


Crest MK4 Rim
  • Rim Weight: 374g (27.5″) / 399g (29″)
  • Wheelset Weight: 1566g (27.5″) / 1638g (29″)
  • Front Wheel Weight: 707g (27.5″) / 743g (29″)
  • Rear Wheel Weights: 859g (27.5″) / 895g (29″)

Stan’s cross-country and gravel-focused Crest rims were not to be left out of the update party. They got bigger, of course, going from wide and 15.8mm tall to 25.0mm wide and 18.0mm tall. And they also went off-center, with 2mm of spoke offset.

Crest S2 Rim
  • Rim Weight: 428g (27.5″) / 457g (29″)
  • Wheelset Weight: 1818g (27.5″) / 1904g (29″)
  • Front Wheel Weight: 831g (27.5″) / 874g (29″)
  • Rear Wheel Weights: 987g (27.5″) / 1030g (29″)

Last and, technically least, the Crest S2 rims went from 23.0mm wide and 17.2mm tall up to 25.0mm wide and 18.0mm tall.

The Hubs:

We got news of two new hubs from Stan’s today, but only details on one. The S2 wheelsets will be built around a hub Stan’s is calling E-sync, which is built to handle the extra abuse of a motor, or maybe just a particularly abusive rider. Stan’s claims a 47-percent increase in torque capacity thanks in part to reinforced pawls that direct stress away from the bearings. The axles are chromoly and the bearings they run on are made by Enduro, including the double-row bearings used in the freehub. All pawls in the E-sync hubs engage simultaneously instead of alternating, but still provide a respectable 8.18-degree engagement. The freehub bodies are available in XD, Micro Spline and HG, and are backwards-compatible with the current Neo hubs.

We have less info on the hubs that will be used on the MK4 wheelsets, dubbed the M-pulse. We’re eager to learn more about them, but we’ll have to wait until the MK4s become available.

Warranty and Advocacy:

Just as interesting, but just as short on details is something Stan’s is calling their Connection program. On top of defining the pretty impressive warranties Stan’s is introducing with the new wheelsets (3-year E-sync hub warranty, 3-year S2 rim warranty with 1-year crash replacement, and 5-year M-pulse hub warranty, 3-year MK4 rim warranty with 1-year crash replacement), the Connection program includes a $10 donation to the advocacy or trail maintenance group of your choice when you purchase a wheelset.