Stans No Tubes Flow MK4 27.5-inch Rear Wheel

More Information
Brand	Stans No Tubes
Colour	Black
Wheel Size	27.5-inch
Tyre Type	Tubeless

Stans No Tubes is the first name in tubeless bike tyre systems. Established in 2000, this small company has a big name and their reputation is known all over the World - Stan's tyre sealant, ZTR rims, tubeless conversion kits, tubeless wheelsets & tyres.

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Stans No Tubes Flow MK4 27.5-inch Rear Wheel

The Flow MK4 wheelset lets you do more. Since 2007, there's a reason the best riders in the world have come to us to ask for Flows. Corner harder, send it further, and carry more speed through any section of trail. Today's Flow MK4 gives you the control you need to push boundaries.

The Flow MK4 rim's patented BST-Asymmetric shape creates the most reliable tubeless seal. The rim's durable 6069 alloy construction and 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. Strength and serviceability are long-standing priorities of every Stan’s wheel, and the Flow MK4 wheel takes those priorities further than ever before. The asym rim design allows for a single spoke length to be used on both the front and rear wheels. As with all Stan’s wheels, traditional J-bend spokes and lacing are used for their proven strength, ride quality, and serviceability.

The M-pulse hubs at the heart of Flow MK4 wheels combine an absolutely bombproof magnetic locking engagement with incredibly smooth rolling. Based on the original innovative Project321 engagement system, the speed and durability of this system is unmatched. Unlike weaker pawl and spring designs, the M-pulse features six pawls with Neodymium magnets that offer virtually no resistance when coasting, but lock the pawl teeth into place far more reliably and consistently than springs. Each detail of the M-pulse hub was engineered to systematically eliminate weaknesses found in other designs. The 17mm axles are made of 7075 aluminum and roll on Enduro brand bearings, including a double-row freehub bearing tested to be far more durable than two individual separate bearings. The entire hub is also shielded, meaning no bearing seal is visible, offering superior protection for all conditions. With only 1.66°of rotating required for the M-pulse hub to engage, power is always instantaneous. Multiple tooth engagement provides a greater surface area to distribute load to improve both durability and speed. The angle of the pawls was even optimized to distribute stress away from the rotating bearings. Beyond the strength and speed of engagement, M-pulse hubs feature adjustable preload, allowing a tremendous decrease in drag for less resistance and more speed.

Available with Shimano Micro Spline, HG, or SRAM XDR freehub, and 6-bolt or Centerlock brake style, with options to fit all popular axle configurations.Tubeless ready with rim tape installed.

Wide, light, strong, and tubeless, the original Flow redefined what a mountain bike rim could do. Today's Flow MK4 gives you the confidence to do even more.

Technology

Stan's 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.

Stan's No Tubes 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.

The Lightbulb.

Too narrow. Tire is constricted, robbing traction and cornering stability.

The Bell.

Too wide. Tire beads are pushed wide, deforming intended tire shape and tread design. Tire has less ability to absorb impacts and less cornering control, and sidewalls are exposed to cuts.

WideRight.

The perfect width. Tire expands to full volume without distortion. Tread pattern and side knobs are in the correct position for cornering, maximum traction and control with minimum rolling resistance.

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.

Stan's WideRight system makes it easy to find the perfect rim width for the tire size and volume you ride. Too narrow of an internal rim mixed with a high sidewall design gives you a "light bulb" tire profile while an ultra wide rim on a narrower tire will give you a flat to "bell shaped" tire profile. Neither of these scenarios give optimal tire profiles nor allows the tire to perform as intended.

WideRight profiles provide the optimal volume without distorting the tread pattern or the side knobs so each part of the tire is in the correct position for rolling and cornering, allowing for maximum traction and control as well as offering minimal rolling resistance. The WideRight profile advantages don't stop there. Proper tire profiles not only allow for optimal tire performance but also allow the tire to do its secondary job of protecting the rim as well as the tire's sidewall. A flat or bell-shaped tire profile leaves the tire exposed to sidewall cuts and creates undue chances for rim damage.

Key benefits:

Optimises tire profiles
Maximizes traction
Properly distributes tire volume
Promotes the design intent of the tire profile and overall tire performance
Reduces tire pinch flats and sidewall damage
Allows tire to protect rim

M-Pulse Hubs

Combining the best materials and construction with a smarter engagement system, M-pulse hubs are built to roll smoother longer. The heart of M-pulse hubs is the magnetic locking engagement system based on the innovative Project321 design and manufactured in their small-batch, high-precision facility in Bend, Oregon. M-pulse freehubs feature six pawls equipped with Neodymium magnets engaging every 1.66° with more force than traditional spring-based pawl designs and less resistance when coasting. With less friction and drag, M-pulse hubs spin more freely to roll further faster, and with less effort.

All hubs suffer from momentum-robbing drag as you coast, but when it comes to creating the most efficient and reliable ratchet system, pulling is better than pushing. Conventional mechanical pawl springs are constantly attempting to push the pawls into the ratchet ring. Those push springs are weakest when fully extended, as the teeth of the pawl engage with the teeth of the ratchet ring, but as you coast and the teeth of the pawl disengage and move down out of the teeth of the ratchet ring, push springs compress and exert even more pushing force. This creates significant drag and friction.

Unlike these inefficient mechanical push spring systems, M-pulse hubs use the pull force of Neodymium magnets to reduce drag to the absolute minimum, while still being able to engage with reliable precision the instant you push on a pedal. Magnetic pull springs are at their strongest when the pawl is engaged and are weakest during coasting, the ideal scenario to reduce drag. Project321’s patent pending placement of the powerful but small rare earth magnets let the pawls self-align quickly and consistently during engagement while creating a hub with almost no rotational resistance when coasting.

The M-pulse hub's six magnetic pawls and hardened steel ratchet ring are also built to outlast conventional mechanical springs, which can fatigue, lose tension, and become misaligned over time. With better durability, stronger engagement, and less drag, the M-pulse design is a better way to build a hub.

Key benefits:

Neodymium rare earth magnetic spring provides stronger engagement with less drag
7075-T6 hub shells and axles can withstand years of high torque use
Fully shielded Enduro bearings with custom grease fill for long life and low resistance
U.S. machined and assembled precision 6-pawl freehub with extremely fast 1.66° engagement
Adjustable preload allows longer bearing life and lower friction to roll smoother
Available in Shimano Micro Spline, HG, and SRAM XDR, 6-bolt and Centerlock, with options to fit most axle widths

More than just smart. Because an innovative design is only as good as its materials and construction, each detail of the M-pulse hub has been engineered to systematically eliminate weaknesses found in traditional pawl and ratchet style hubs. The new M-pulse hub starts with the most simple and durable version of Project321’s magnetic pawls, and features an all new freehub body and main seal design for outstanding protection from the elements. The hub rolls on Enduro bearings with a custom grease fill optimized for low resistance, and every bearing on the M-pulse hub is shielded, meaning no bearing seal is directly exposed, for smooth rolling in all conditions and increased bearing life. The 17mm axles are made of 7075 aluminum and roll on long-lasting Enduro brand bearings that feature custom-tuned grease fills that reduce resistance. A double-row main freehub bearing was chosen after tests proved it to be more durable than two individual, separate bearings. Multiple teeth on each pawl provide a greater surface area to distribute load to improve engagement, and the angle of the pawls was optimized to distribute stress away from the rotating bearings for added durability under high torque.

Beyond the strength and speed of engagement, M-pulse hubs feature adjustable preload that decreases drag and resistance for less effort and more speed. Adjustable preload also prolongs bearing life by allowing the hub's bearing tension to be tuned with greater precision in contrast with most hubs that tension unevenly by relying solely on how much the bike’s axle has been tightened. A precision piece of equipment deserves the option of precise tuning, and the M-pulse hub's adjustable preload, available on both the front and the rear hub, delivers that level of tuning precision.

With their quality materials and construction, M-pulse hubs are backed by a 5-year warranty.

M-pulse hubs are available on MK4, CB7, and Podium series wheelsets, and are offered with Shimano Micro Spline, HG, or SRAM XDR freehubs, 6-bolt or Centerlock brake style, and options to fit all popular axle configurations.

Oh, and how does it sound? Here's the M-pulse hub compared to some other popular hubs.

Features

Low-profile 30mm internal width optimizes tire shape, traction, and control for 2.3-2.6” tires
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
M-pulse ultra-low drag magnetic pawl adjustable hubs with 1.66° engagement
Enduro bearings with double-row freehub bearing
Matched wheelsets use traditional J-bend lacing and share a single spoke length for easy serviceability
Connection program includes 5-year hub warranty, 3-year rim warranty, 1-year crash replacement, and $10 donation to trail maintenance or advocacy group of your choice