STAN'S NOTUBES WHEELS
We can't think of a more polarizing debate in the cycling world than the hot-faced arguments surrounding the pros and cons of 26in vs. 29in wheels. Well, we have advice for both sides of the fence -- the middle path is usually the wisest. Luckily, our statement isn't in vain, as the Stan's NoTubes ZTR Crest 27.5in Wheelset walks on the line that both parties have drawn in the sand.
Now, we're not going to pick a side on the war of merits, but we can say that 27.5in makes perfect sense to us. After all, if you believe the campfire stories, the 27.5in wheel was intended to be the original mountain wheel size, with the 26in falling into our laps by default, or in this case, by exorbitantly high tariffs. Also known as 650b, 27.5in offers the best of both worlds. As an adopted standard, it provides logical proportions for frame sizing and does away with limitations on suspension travel. As the in-between'er it offers a close-fit to the nimble handling of 26in while retaining the smooth-rolling of 29in. With 27.5in, traction is also increased, and the feel of natural, effortless climbing doesn't come with the compromise of sluggish descending. Sounds good, right? Well, the ZTR Crest wheelset takes all of these features a step further.
The ZTRs are Stan's first go at 27.5in wheels, but you wouldn't guess that from the ride quality. Made from 6061 alloy, the ZTRs rim profile provides well-rounded characteristics of rigidity, stability, and strength. However, the profile and material are only cogs in the efficiency machine known as Bead Socket Technology (BST). This is Stan's signature on the wheel world, and we'll tell you why it's so important -- it all comes down to lower tire pressure. BST eliminates the necessity for a bead hook, and allows the rim to use a shorter sidewall. This design permits the tire to inflate to its natural shape, and thus reduce the stored energy within the rim. Now, to draw comparison to a typical design with a heightened sidewall and bead hook, this system pinches the tire at its base and requires higher inflation pressures to maintain handling. This pre-loading is what contributes to higher stored energy, and accordingly, it contributes to the characteristic of 'rolling off' or instability under lateral pressure, or as it's commonly known, 'cornering.' In contrast, BST actually reduces required pressure by around 30%, and this contributes to a multitude of advantages.
With BST's design, tires can inflate to a higher volume at a reduced pressure. This translates to a true tire shape that grabs the trail more thoroughly through corners. The lower pressure also directly equates to speed. Tires roll faster at reduced pressure by efficiently adapting to rough or uneven surfaces. With less pressure, the tire is free to absorb shock instead of recoiling from it, and this amounts to less energy being dissipated by the tire flattening and rebounding upon impact. Further along the lines of speed, the ZTR's absence of a bead hook not only reduces the weight of the wheel by around 35g, but it also sets in motion a design that removes grams from the most important location -- the point of rotation. By removing the bead hook, the rim is naturally made wider. Width breeds stability, and stability permits a 2-4mm height reduction to the sidewall. The shorter sidewall reduces air pressure's mechanical leverage enacted upon the rim, which means that Stan's can make the center of the rim thinner. All in all, the chain of events reduces weight by around 100 to 160g without compromising strength or rigidity. Back on point, though, it's important to note that this weight was removed from the rim. This means that rotational weight is decreased, and thus, less energy is required to achieve acceleration and to keep the wheels rotating at speed. You'll also be happy to know that, should you choose to run a tube, the ZTR design also greatly reduces the occurrence of pinch flats. And even better, when run tubeless, there's simply no tube to pinch flat.
The ZTRs accept a 6-bolt rotor. The rims have been laced in a 32/32 three-cross pattern to Stan's 3.30 QR Disc hubs.
The Stan's NoTubes ZTR Crest 27.5in Wheelset are available in a 27.5in (650B) size and in the color Black.
Please note that this wheelset features a quick-release front and rear axle type. Any required/desired conversion kits for 15mm or 12x142 must be purchased separately.