TESTED: Stans Flow EX3 mountain bike wheels

Words: Hayden Wright |n Photos: Gerard Lagana

Stan's is a name synonymous with one thing – tubeless wheel technology. Similar to brands like Hoover, Kleenex or Jacuzzi, their likeness is so tightly bound to their flagship offering that many of us refer to the name in reference to the product, not the other way around. I would not hazard to guess that most readers of this very publication have poured a glug of Stan's sealant into their wheels at one point at another. Latex based fluid aside, Stan's also produce a wide array of rim tapes, valves, and wheels such as the mid-priced alloy Flow EX3 wheel set I have on test.

The Hub

At the foundation of this wheel set is Stan's own E Sync Hub. Developed with a primary focus on reliability, this hub combines a 6066 aluminium body with a chromoly axle and heat-treated 44t steel ratchet. Rolling on enduro bearings, these hubs are available to all common freehub types, spacings, and rotor standards.

What really caught my eye was the E Bike compatibility and claimed 47% increase in their maximum torque ratings over their Neo hubs, on which I have previously put hundreds of hours of problem free use. To further the user-friendly nature of these hubs, Stan's have designed the flange profile to allow for equal length spokes on both sides of the wheel when laced with compatible rims. A performance benefit? No. But having to carry, or find less variations of a J-bend spoke in case of an emergency is a fantastic feature and drastically decreases the odds of a snapped spoke in some obscure length or shape ruining your weekend – trust me, I’ve been there.

The Rim

With a claimed weight of 618g (29”) / 580g (27.5”), 32 spoke holes, and an inner width of 29mm the aluminium Flow EX3 Rim is in direct competition with familiar faces such as the venerable EX511 from DT Swiss and Hope’s Fortus 30. Where this rim stands out from the crowd is hidden in the details, with Stan's putting a concerted effort into the design of the rim profile to ensure durability through dent prevention. This has been realised primarily through the reinforcing of the sidewalls, with an additional ‘tiebeam’ section of alloy added from the sidewall to the belly of the rim to help decrease the likelihood of damage from impact.

When combined with Stan's patented bead lock technology (BLT) which guarantees the best possible seal of the tyre to the rim, and the low wall height, you have a welded rim which in theory should be ready to take hits for hours upon hours of use without as much as a burp or wobble.

The Build

The EX3 Rim and E Sync hub are laced together with Sapim D-Light spokes and brass nipples to form the complete EX3 wheel set. For my specific testing purposes I requested a set of mixed wheels (29”/27.5”), with a Microspline freehub, 6 bolt rotor interface and boost spacing. With Stan's rim tape and valves installed, they weighed in at 1036g (F, 29”) and 1135g (R, 27.5”). As I had anticipated, mounting up a set of tubeless tyres on this wheel set was one of, if not the easiest instals I’ve ever completed. With tape and valves installed from the factory, I proceeded to pair the EX3 wheels with a set of Pirelli Scorpion Race EN tyres.

These were easily mounted by hand and inflated with my track pump. No sweat, frustration, snapped tyre levers or spilled sealant here – just the satisfying crack of each tyre beading onto the rim with ease. Over the course of testing I noticed very little drift in pressures both during and between rides, proving that both the bead/tyre interface and factory tape were doing their job superbly as promised by the aforementioned BLT.

On The Trail

Initial impressions when I spun these wheels up in my workstand for the first time was just how easily they rotated. A little test I like to do is turn the front wheel by hand and just watch to see how much drag the hub has. The gold standard for me is a wheel which will slowly rock back and forth until the valve is resting at the 6 o'clock position – which the EX3 front wheel achieved. Similarly, I like to see if the rear wheel will take a minor rotation clockwise as it slows to a stop, resting on the most recently engaged pawl position. Another gold star here for the E Sync hubs. While bearings do wear in and get faster over time as the grease settles into the balls and the seals find their final home, I find it a good indicator of how freely everything is working out of the box. The 4 freehub pawls provide a nice whir, but are well greased out of the box which keeps the sound muted without being entirely silent.

My first ride on these wheels was at a local spot which is fairly flat and full of hard rocky impacts and stout sprinting sections. It was on these sprinting sections that I noticed the firm engagement of the hub, never slipping or skipping a beat. No matter how hard I got on the gas the E Sync steel ratchet took it in its stride, coming back for more. Similarly, I enjoyed the positive engagement from the hub on some short technical climbs. To me, the minimum engagement you need on a hub before I start to notice lag when pedalling is around 10° or 36t, which these hubs satisfy at 8.18° / 44t.

It was on this first ride that I also heard a handful of audible rim impacts from the front wheel. A sound that would once make me shiver up my spine, I waited for the seemingly inevitable hiss which typically accompanies an alloy rim ding. However there was no issue, the Flow EX3 rims seemed to take any impact I could throw at them in their stride. While testing these wheels I was also playing around with some pressures on the Pirelli Scorpion Race tyres I had mounted, going down to 22 psi on the rear and 18 psi on the front – what I consider to be dangerous territory on an alloy wheel with no inserts. I am no hack, but we all make mistakes and I was pleased to see these rims still running true after more than one bad line choice. At these low pressures there were some noticeable fold lines on the sidewalls of the tyres, but fortunately no noticeable sealant loss or burping. Spoke tension on the rear wheel did require a quick adjustment after around 10 hours use, but I would consider this typical for an alloy wheel set after its bedding in phase.

Ride character of these wheels was very similar to that of other DT Swiss wheels I have had in the past, and had no discernable traits either positive or negative which I can speak to. In comparison to the WAO Union wheels which I typically ride, trail chatter and subsequent vibrations were more prevalent through my hands and feet as speeds increased. I did miss the dampening characteristics of those wheels at times, but did enjoy the increase in lateral flex which these alloy wheels have. This was particularly noticeable on high speed off camber sections, where square edged chattery impacts would be sucked up by the wheels through the compliant nature of both the rim and overall wheel build.

At the time of writing I am yet to need to perform any maintenance on the wheel set at all, but it is worth noting that Stan's offers comprehensive service catalogues and individual part numbers on every component when the time does arise. This is also backed up by a 3 year manufacturing and 1 year crash replacement warranty.

Verdict

With the Flow EX3, Stan's have delivered a wheel set that should be at the top of the list for any gravity focused rider who prioritises reliability and serviceability just as highly as performance. Through testing they have eaten up everything I have thrown their way, showing that the slight penalty on the scales compared to some of the competition is worth every gram. While there are louder, brighter and lighter wheels available the value on offer here is hard to beat for a budget conscious enduro or downhill rider.

RRP: $650 (rear), $400 (front)
From: jetblackproducts.com

Hits
– Smooth, fast, reliable hubs
– Quick and problem free tubeless setup
– Rims are dent free after multiple impacts
– Matched spoke length across a wheel size

Misses
– None so far