Stan's NoTubes Crest MK4 Gravel Wheels in Review

Stan's NoTubes was founded in 2001 by Stan Koziatek and is considered a pioneer of MTB tubeless systems. Over the years, the Americans have developed not only a range of patented products, including tubeless sealant, valves, rim tapes, rims, and complete tubeless wheelsets, but also inspired the entire bicycle industry to introduce new tubeless tires and technologies.

Around 20 years after the first tubeless-ready hollow chamber rim, which was specifically developed for tubeless use, Stan's NoTubes now presents the fourth generation of their Crest rims and Crest wheelsets. The new asymmetrical Crest MK4 aluminum rims are available in three updated widths and - according to their intended use - specially crafted, consistently wider rim shapes, each with its own spoke hole offset. The wheelsets presented here for Gravel/XC have an internal width of 25 mm and a spoke hole offset of 1.5 mm and are designed with reinforced spoke beds and welded seams for both the higher pressure of 40 mm gravel tires and the lower pressure of 2.3" MTB tires. Available with Shimano Micro Spline, HG, or SRAM XDR freehub, optionally with 6-bolt or centerlock brake mount, and with options for all common axle configurations for road and MTB.

We subjected the 29er version (29-inch MTB = 28-inch road) including the newly spoked M-Pulse Premium hubs to a rigorous test on the gravel bike.

Before the GRX cassette could be mounted, the freehub had to be swapped for one with the Shimano HG standard, as we originally received one with Microspline (see studio photos). However, the exchange went smoothly despite the above-mentioned complexity of the freehub assembly. The tolerances also fit: cassette tightened, DT Swiss GRC wheels out, Stan's with identical tires in, and the discs were immediately rub-free. Additionally, the gear shifting worked precisely without readjustment.

In direct comparison to my 42-millimeter high GRC 1400 wheels, the side wind susceptibility of the Crest was significantly less pronounced, and the comfort on rough terrain was relatively decent. Unsurprisingly, a slightly better power transmission or liveliness at the rear wheel, which was likely due to the 216 engagement points on the freehub and the lower weight, was noticeable. Especially in very slow, technical sections, the faster pawl engagement was noticeable, as even the slightest pedal stroke was enough to accelerate the ride again.

Overall, I would like to attest that the Crest MK4 wheels offer a good compromise between stiffness and comfort - at least in tubeless operation. The wheels are not overly hard, but still quite stiff and easily handled even the most aggressive sprints. On descents, they absorbed even the hardest bumps and potholes thanks to their wide rim bed and solid tire seating, while still providing good stability and neutral handling characteristics despite the low tire pressure.
I particularly enjoyed the sonorous hum of the freewheel when coasting. "Similar to a rattlesnake" probably best describes the dull soundscape, though not nearly as loud as the past angry-bee orgies of a Chris King. If you want it louder, you could opt for a thinner grease or oil around the pawls - but personally, I don't see the point in that.

Regarding the build quality, the rims, spokes, and hubs held up very well, even though I spent most of the time riding in really grimy autumn/winter weather and had to give the gravel bike at least five major washes. There were also no punctures, although the 40C semi-slick on the rear wheel felt subjectively at its limit concerning impacts - better to go all out and mount one with a width of 45 millimeters.

The only thing that couldn't fully convince was the non-drive side bearing seal on the rear wheel. While it's hard to say whether it was due to rain, mud, road salt, or an overly intensive bike wash, rust did form on the left bearing, and it felt a bit "gritty" when rotating. The issue could be fully resolved with a small bearing service (cleaning with brake cleaner, re-greasing with bearing grease) but should be monitored.

With the market introduction of their Crest rims in 2005, Stan's NoTubes wrote a part of mountain biking history. These could be run tubeless without any issues and were considered lighter and more durable than other products available on the market. Although the design of the fourth generation Crest presented here still doesn't look particularly exclusive, it follows the same vein and shines with a light 6069 aluminum alloy, 25 mm internal width, and for the first time, an asymmetric profile.

Features of the rims include easy tire mounting, excellent sealing at the rim flange, and approval for 40 mm wide gravel tires or a maximum of 2.3-inch MTB tires. Inspired by Stan's carbon rims (BST-Asymmetric rim design), the new, wider rim profile increases lateral stiffness as well as impact robustness and reduces the risk of snakebites. Furthermore, the tire volume can fully unfold thanks to the low rim flange, resulting in lower rolling resistance, optimal damping behavior, and high tire stability.

A real eye-catcher, however, are the new M-Pulse Premium hubs, which blaze new trails with high-quality Enduro bearings and the innovative magnetic pawl design from Project321, promising high durability with optimal power transmission.