Over the years, Stan's aluminum Flow rims have earned a reputation for reliability, the type of rims that can easily be built up into a durable wheelset capable of withstanding the punishments of weekend warriors and professional racers alike. The torch was recently passed from the Flow EX model to the new Flow MK3, which is lighter and wider than its predecessor, measuring 29mm internally versus the EX's 25.5mm width.
A Flow MK3 rim alone will set you back $100 USD, or you can purchase a full wheelset in any wheelsize built around Stan's own Neo hubs for $679 USD. Our 29” wheelset weighed in at 1870 grams – 890 grams for the front wheel, and 980 for the rear with an XD driver.
Flow MK3 29 Details
• Size: 29" (27.5" and 26" options available)
• Intended use: all-mountain
• Internal width: 29mm
• Rim material: 6069 aluminum
• 32 spokes, 3x pattern
• Weight:1870 grams; Front: 890 grams, Rear: 980 grams
• MSRP: $679 USD
Stan's Neo hubs use a four pawl design, with each pawl sitting on a small leaf spring. Those pawls ratchet against the 36 steel teeth located inside the hub shell, creating 10-degrees between engagement points. Compared to Stan's previous hub design, the Neo now uses larger cartridge bearings (6902 instead than 6802), a change that was intended to increase their lifespan. Multiple end caps are available, and the wheels come with 15x100, 20x110, and quick release end caps.
The wheels are laced up with the tried-and-true, 32 spoke, three cross pattern – there aren't any proprietary spoke nipples or hard to find straight pull spokes to be seen, making it that much more likely that a shop will have a replacement in stock.
36 teeth create 10 degrees between engagement points.
The freehub body uses a fairly standard four pawl design.
Stan's may be well known for their rims, but their tire sealant is what really put them on the map, so it only makes sense that MK3 rims are designed to be run with tubeless tires. The rim's depth is only 16mm (versus the previous version's 17.8mm), a design that's meant to securely hold a tire's bead while allowing the rest of the tire to expand into its natural shape. The shallow sidewall depth is also intended to reduce the likelihood of a pinch flat – there's less material for a tire's sidewall to get smashed against during a hard hit.
The aluminum rims measure 29mm internally, and 32.3mm externally.
The rims come with tape and valve stems pre-installed in order to make tubeless setup even easier.
Our test wheelset spent a good chunk of the season mounted up on Nukeproof's Mega 290, a bike that likes nothing better than plowing straight through anything that's unfortunate to get in its path. In other words, a good bike to for testing wheel durability. Bontrager's 2.35” SE5 and Schwalbe's 2.3” Magic Mary tires both saw use during the test period, and there weren't any issues getting them set up tubeless and securely seated using only a floor pump. Pressures hovered around the low 20s depending on conditions, typically 21 psi for the front and 23 psi for the rear.
The MK3 wheels fall into the set-and-forget category – once they're mounted up they fade to the background, free of any unwanted flexiness or disconcerting noises that would call attention to them. They're stiff without being harsh, and while I didn't have a set of Flow EX wheels on hand to perform a direct comparison, the MK3s certainly felt on par with the previous version. Even on the rough and chattery trails in the Whistler Bike Park they were well mannered, emerging without any cracks or flat spots. I did re-tension the spokes after those days in the park, but that's pretty typical after a solid round of lift-served laps. The rims have renained dent free, and there weren't any pinch flats or burped tires during testing. As far as the weight goes, 1870 grams is very reasonable for a 29" wheelset that's meant to be able to handle a good amount of abuse, especially considering the price.
The hub's 10-degrees between engagement points might not be as lightning-quick as higher end options like Industry Nine or Chris King, but I also never found myself wishing “If only my rear hub engaged 3-degrees quicker..” There weren't any instances of the freehub body slipping or popping either – like the rims, the hubs simply did their job without causing a fuss, although I did run into an issue that's detailed below.Issues
The bearings in the front hub are still spinning smoothly, but the inboard bearing on the freehub body died a premature death, becoming rough and difficult to turn much earlier than I would have anticipated. While disassembling the hub, I found that the tolerance between the axle and the cartridge bearings was unnecessarily tight, making removal and replacement extremely difficult. According to Stan's, the reason for this problem was that during the second production run a "small change to the axle caused it to be slightly oversized, in turn causing the tight fit and premature roasting of that bearing." The issue has since been corrected, and the inside of the new axles is black rather than silver to make identification easier. For affected customers, Stan's has been sending out a new axle and an upgraded six-pawl freehub body to help make up for the inconvenience. Pinkbike's Take
|The new MK3 rims proved to be worthy of carrying on the Flow name, and took all the abuse they were subjected to without flinching. The rear hub didn't fare as well, but Stan's have addressed the issue and taken steps to correct it, although if I were in the market for a tough and reasonably light wheelset I'd be tempted to go the handbuilt route and lace a pair of Flow rims up a set of Hope or DT Swiss hubs. - Mike Kazimer|
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