Stan’s NoTubes Flow MK4 Rim

Since its debut in 2007, the Flow Rim has set the benchmark for riders determined to push limits and progress further. The original Flow redefined what a mountain bike rim could be—lightweight, wide, strong, and fully tubeless-ready—pioneering a new era of aggressive trail and enduro riding. The Flow MK4 continues that legacy, advancing the design with a 30mm asymmetric profile for a stronger, more balanced wheel build and unmatched trail confidence.

Built from high-strength 6069 aluminum with a welded joint and reinforced spoke bed, the Flow MK4 offers exceptional durability and control. Its BST-Asymmetric shape perfectly balances the resistance to dents and tire bead retention on both sides of the rim—delivering precision and reliability even in the harshest rock gardens or under the hardest cornering. Combined with Stan’s patented Bead Socket Technology, it provides effortless tubeless setup and the most secure airtight seal available.

Tested at the highest levels of freeride and downhill—from Red Bull Rampage lines to technical enduro stages—the Flow MK4 stands as the evolution of a legend, ready to take your riding further than ever before.

Key Features

• 30mm internal width enhances tire shape, grip, and control for 2.3–2.6” tires

• 6069 aluminum construction with welded joint and reinforced spoke bed for exceptional durability

• BST-Asymmetric rim design balances spoke tension for a stronger, more stable wheel build

• Patented Bead Socket Technology (BST) ensures the easiest tubeless setup and most secure seal

• Low-profile shape for improved ride quality and reduced risk of pinch flats

• 3-year warranty and 1-year crash replacement program for total confidence