Press Release

Stan’s NoTubes Introduces Flow EX3 Rims and Wheelsets

Design promises a new level of reliability for enduro, downhill and trail Bikes.

Stan’s NoTubes is proud to introduce the new Flow EX3, an extremely durable new line of rims and wheelsets designed for downhill, enduro and the most demanding trails. Based on the legendary Flow EX, the new Flow EX3 rim features Tiebeam, an internal reinforcement that offers unmatched impact resistance and the best air retention of any tubeless rim. The Flow EX3 combines the incredibly durable Tiebeam design of Stan’s classic Flow EX with the 29mm internal width and 6069 aluminum construction of the popular Flow MK3 to create an entirely new rim built to handle today’s faster, heavier and more capable enduro, downhill and e-bikes. While still delivering the outstanding ride quality for which all Stan’s rims have come to be known, the new Flow EX3 is unapologetically focused on descending, speed, air retention and durability.

Stan’s has supplied rims to Downhill World Cup and Enduro World Series teams for years, but the Flow EX3 is the first rim specifically designed from the ground up to handle these more severe riding conditions, and it is already a proven winner. In late 2018, GT Factory pro rider Martin Maes rode a Flow EX3 rear wheel to a win at the Enduro World Series round in Whistler and then to a World Cup Downhill victory in La Bresse.

For 2019, look for Flow EX3 rims and wheels on the bikes of the GT Factory Racing team, Atherton Bikes team and the Propain Factory team.

Flow EX3 rims and wheelsets are in stock and shipping to favorite local bike shops. They are also available from distributors and directly from


During extensive testing of Stan’s and competitors’ rims during the development of the Flow EX3, the key advantage of Stan’s successful Flow MK3 rim, released in April 2016, was determined to be its 6069 aluminum construction, which is 10-15% stronger than the more commonly used 6061 alloy. The Flow MK3’s radially compliant rim shape and 29mm internal width also tested extremely well. More surprising was the strength of Stan’s classic Flow EX rim, which used internal reinforcements to create a triple-cavity design. Though not made of the more durable alloy, and narrow by today’s standards, the old Flow EX demonstrated amazing strength during testing. Combining the best of these designs, increasing wall thickness at the spokes and utilizing a new “BBQ” shot-peened finish created a rim that exceeded all testing goals and proved much stronger and more impact resistant than any other. This is the new Flow EX3.

Kyle Warner helped test the new Stan’s NoTubes Flow EX3 rims and wheelsets. They are built to handle faster speeds on the most demanding trails. The Flow EX3 rim’s Tiebeam inner bridge and 6069 alloy combine to offer unmatched reliability, withstanding impacts that would deform most rims to the point of air loss Stan's NoTubes

More than just strong, the Flow EX3 rim is designed to prevent air loss. Even when used with a tire insert, huge impacts can cause the sidewall of most rims to fold, causing air loss and eventual failure, but the Tiebeam internal brace and patented low-profile sidewalls of the Flow EX3 resist this folding, maintaining air pressure and structural integrity better than any other rim, even under the most severe impacts.

The Tiebeam design also allow tremendous strength increases with only minimal weight increases. The 27.5” Flow EX3 rim weighs 580g, while the 29” version weighs only 618g.

Like all Stan’s rims, the Flow EX3s are easy to set up tubeless. Thanks to Stan’s proven Bead Socket Technology, all that’s needed is a floor pump. Optimized for 2.35” to 2.8” tires, the Flow EX3 expands the Flow line to handle the most aggressive riding. Every Downhill World Cup and Enduro World Series ride, every hour of testing, riding and improving, it’s all here in the new Flow EX3.


Building the Flow EX3 wheelset starts with Stan’s Neo OS front and rear hubs. The Neo OS front hub features larger bearings than conventional Neo hubs, while still being compatible with both 20mm and 15mm forks. The Neo OS rear hub rolls on a steel axle for increased durability and includes a Durasync freehub with reliable, simultaneous six-pawl engagement.

The Flow EX3 wheelset continues Stan’s tradition of using readily available, non-custom j-bend spokes in lengths that are commonly in stock in bike shops around the world. The Flow EX3’s Sapim D-Light spokes keep rotating mass to a minimum and offer exceptional strength, while Sapim’s Secure Lock alloy nipples provide a mechanical lock to resist loosening.

Flow EX3 wheelsets are available for Shimano or SRAM XD cassettes and all current axle systems, including 110mm front and Boost 148mm, 150mm, and Super Boost Plus 157mm rear spacing. New for 2019, a Neo OS front hub with wider flanges is also an option to fit forks that require the wider “20x110 Boost” disc brake spacing.

Complete Flow EX3 wheelsets come ready to set up and ride with pre-installed rim tape for tubeless use and presta valves. 15x110mm OS front wheels also come with an additional set of 20mm OS Boost end caps.

Flow EX3 wheelsets are available in stock and custom configurations. Decal colors and build configurations can be specified using Stan’s Custom Wheel Builder at


Flow EX3 rims come with a two-year warranty and one year of no-fault crash replacement.

Flow EX3 Specifications

  • Uses: Enduro & Downhill
  • Internal Rim Width:29.0 mm
  • External Rim Width: 32.6 mmRim Depth: 17.9 mm
  • Optimal Tire Sizes:2.35” to 2.8”
  • Hubs:Stan’s Neo OS with Durasync
  • Spokes: Sapim D-Light Black 2.0/1.65/2.0mm
  • Nipples: Sapim Secure Lock Alloy Black
  • Hole Count: 32-holeDrilling Style: Symmetrical
  • Rim Material: 6069 Aluminum AlloyRim Color: Black Bead Blasted Finish (BBQ)Hub Color: Black
  • Brakes: Disc only
  • Wheelset Weight:2,018 g (27.5") / 2,115 g (29")
  • Rim Weight:580 g (27.5") / 618,g (29")
  • Front Wheel Weight:932 g (27.5") / 981 g (29")
  • Rear Wheel Weight: 1,085 g (27.5") / 1,134 g (29")
  • ERD:564 mm (27.5") / 602 mm (29")
  • ETRTO: 584x29.0 (27.5") / 622x29.0 (29")
  • ISO:27.5"x32.6 mm / 29"x32.6 mm
  • Tape:30 mm
  • Valve:35 mm Presta
  • Max Pressure Tire Pressure: 37 psi (2.4”), 26 psi (2.8”)
  • Max Rider Weight:250 lb (113 kilo)Max Spoke Tension: 125 kgf (1,225 N)
  • Wheelset MSRP: $699
  • Rim MSRP:$115

Martin Maes (Team GT) is racing on the new Stan's Flow EX 3 wheels. He's already won one round of the Enduro World Series and one of the Downhill World Cup on a new Flow EX3. Stan's NoTubes

#StansNoTubes #FlowEX3 #tubelessgoesfearless #onlystans 


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