Stans No Tube Flow Mk4 Rim

Since 2007, the Flow rim has been helping riders progress, push boundaries, and do more on their bikes. The original Flow was light, wide, tubeless, and strong as hell. It redefined mountain bike rims and played a role in the evolution of riding. Today's Flow MK4 continues the progression with a 30mm wide asymmetric rim designed to build an even stronger overall wheel.

Durability and an almost uncanny feeling of control on the trail have made Flow rims the preferred choice of multiple Red Bull Rampage riders, and today’s Flow goes even further. The Flow MK4’s reinforced spoke bed, combined with the offset drilling of the asym design, builds into an incredibly durable wheel that brings added confidence to every ride. Unlike many asymmetric rims, the Flow MK4's BST-Asymmetric shape is designed to equalize resistance to dents and tire bead retention on both sides of the rim under even the worst rock gardens and hardest cornering. Combined with Stan's patented Bead Socket Technology, the Flow MK4 rim offers the easiest tubeless setup and most reliable airtight performance on the trail.

Ramp up your progression and make every ride even better with the confidence of Flow MK4 asymmetric rims.

Technology

BST-Asymmetric Technology

BST-Asymmetric rims combine Stan's patented Bead Socket Technology--the original and still most reliable tubeless-ready rim design--with an asymmetric shape that allows for offset spokes, creating a stronger overall wheel. Most asymmetric rims struggle to inflate easily and maintain a reliable seal on both sides of the rim, but Stan's BST-Asymmetric rims equalize tire retention and dent resistance on each side of the rim, allowing for easy inflation and total ride confidence under even the hardest cornering.

Stan's BST Asymmetric rims feature distinct spoke hole offsets based on rim width. At 25mm wide, Crest MK4 rims have 1.5mm of spoke offset. The 28mm Arch MK4 rims use an offset of 2.5mm. The 30mm wide Flow MK4 rims use a 3mm offset. This level of precision optimizes spoke tension balance and allows for the strongest and most effective tubeless rim shape. The Crest MK4 asymmetric rim, for instance, has a near perfect 92% balance between drive side and non-drive side spoke tension, versus the 58% spoke tension balance of previous symmetric Crest MK3 rims. When used with M-pulse or E-sync hubs, Stan's MK4 BST-Asymmetric allows a single spoke length to be used for all matching sets. Whether you choose a MK4 wheelset with M-pulse hub or S2 wheelset with E-sync hub, a complete set of Stan's Crest, Arch, or Flow wheels will each use only a single common and readily available spoke length that works front or rear, either drive side or non-drive side, making maintenance and service easier than ever.

WideRight Rim Design

The most important piece to the bicycle-terrain interaction is the contact patch between the tire and terrain, so tire profile and tire pressure play huge roles in bicycle performance and overall handling. But many rims just don't work well with the tires we're all using. Rims that are too narrow fail to offer sufficient sidewall support and protection to your tires and create a less stable shape. The result is less control in the corners, less traction on climbs, and more rolling resistance. Rims that are too wide also distort the tire profile, decreasing traction and control and driving impacts directly into the rim, negating the impact absorbing advantages of a tire's volume. Our WideRight rim widths are designed to strike the perfect balance between tire volume and sidewall function.

WideRight rim profiles allow the tire to achieve its proper shape, and that's the foundation for a great handling, fast-rolling, and responsive bike.

Features

• Low-profile 30mm internal width optimizes tire shape, traction, and control for 2.3-2.6” tyres
• Durable 6069 aluminum with welded joint and reinforced spoke bed
• BST-Asymmetric design combines Stan’s legendary easy tubeless inflation with a stronger, more balanced wheel build
• 3-year rim warranty with 1-year crash replacement