The Stans No Tubes Flow EX3 wheelset is based around American brand Stan’s No Tubes’ toughest rim, and is built for heavy duty abuse.
Made from stronger 6069 alloy with 32 spoke holes, Stan’s No Tubes Flow EX3 wheelset is rated for enduro or even DH use and measures 29mm internally. Taller than a Stan’s Flow MK3, rim walls are also thicker for extra dent resistance and stiffness. The brand is so confident of its strength, in fact, it outright claims more impact resistance than leading competitors like the highly-rated DT Swiss EX511 enduro rim. It does weigh 50g more, however.
Internally, the EX3 uses a double-layer reinforcing beam (that narrows to a single layer in the centre) between sidewalls, with a traditional hooked bead lip. Stan’s says this design offers greater resistance to crushing rim walls and helps prevent dings or dents affecting the ability to seal tubeless tyres.
Sticking with the durability theme, Stan’s Neo OS hubs use larger diameter bearings and also a stronger steel axle. Hubs are laced with standard, easy-to-source Sapim D-Light J-bend spokes, and the rear freehub has triple-stacked bearings for extra stiffness. The six-pawl design also targets robustness and engages directly with the 36-tooth steel drive ratchet for 10º pick up, which is slightly slower than most.
One issue with Flow MK3 rims is we’ve seen them crack at the spoke holes, but the EX3 is more teardrop shaped, uses extra material and has a completely different profile at the eyelet. Certainly we had zero damage on our set, even with it having seen a lot of action on a 180/190mm travel 29er. Multiple hard impacts and continual smashing through roots and rock gardens left the shot-peened rims unscathed, and on top of this, there’s a solid and tight feel, even under the massive cornering forces you can generate with so much travel.
Despite never distorting, twisting and twanging in deep pocket berms on DH tracks, the EX3s also never feel overly harsh or pingy when skipping across roots or pointy rocks on more natural terrain.
On our shorter travel test rig, the feel of Stan’s No Tubes Flow EX3 wheelset is noticeably heavier uphill than some (the 29er rim weighs a chunky 618g), but actually zip along and turn over efficiently everywhere else with smooth rolling, good acceleration and a direct feel under power.
While most wheels this weight can feel like too much to drag around on an enduro bike, that's not the case here, making them impressive all-rounders and recommended for heavier or demanding riders after a really tough set of aluminium wheels for DH or enduro racing.