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.

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

Flow MK4 wheels include pre-installed tape for tubeless use and presta valves.

3-YEAR ALUMINUM RIM Warranty AND CRASH REPLACEMENT POLICY

3-YEAR ALUMINUM RIM Warranty:
Stan’s MK4, S2, and EX3 series aluminum rims are covered under a 3-year Warranty against manufacturing defects from the original purchase date. Warranty does not cover abuse, misuse, consequential damages, normal wear and tear, damage resulting from crashes, or improper installation. Warranties only apply to the original owner. If a product is found to be defective, a free repair or replacement will be provided at the sole discretion of Stan’s. Purchases made through unauthorized resellers such as eBay, Alibaba, Amazon or similar resale sites are not supported under our Warranty policy.

ALUMINUM RIM Warranty PROCESS:

1. Retain a copy of the original proof of purchase (i.e. Itemized receipt or invoice)
2. Submit your claim via an authorized Stan’s dealer with your proof of purchase or contact us at Warranty@notubes.com with a description of your issue, a photo that helps illustrate the issue, and your proof of purchase
   Note: For Warranty and crash replacement inquires outside the United States, please contact your local dealer or distributor
3. The dealer will contact Stan’s or the local distributor and arrange for repair/replacement, or, if you’ve contacted us directly, we will work quickly to reply to your email with instructions
4. If you have contacted Stan’s directly regarding a wheelset Warranty, and your approved request requires a return, Stan’s will provide you with a shipping label for return, free labor for your wheel rebuild, and return shipping

1-YEAR ALUMINUM RIM CRASH REPLACEMENT:
Should you have the unfortunate experience of crashing and damaging your Stan’s aluminum rims, we want nothing more than to help you get back on the bike as quickly as possible. The Crash Replacement Policy covers the rims for a period of 1 year from the original purchase date against damage caused during normal operation of the bicycle, including racing. Crash replacement aluminum rim pricing is 50% off the MSRP of the exact or comparable product at the time of the claim. If necessary, spokes, nipples, tape, and costs associated with any build labor performed by Stan’s will be provided at a discount.

ALUMINUM RIM CRASH REPLACEMENT PROCESS:

1. Retain a copy of original proof of purchase (i.e. Itemized receipt or invoice)
   Note: Reply to the registration confirmation email with a picture or scan of your receipt and we’ll keep it on file for you in the event of a future claim
2. Submit your request via an authorized Stan’s dealer with your proof of purchase or contact us at Warranty@notubes.com with a description of your issue, a photo that helps illustrate the issue, and your proof of purchase
   Note: For Warranty and crash replacement inquires outside the United States, please contact your local dealer or distributor
3. The dealer will contact Stan’s or the local distributor and arrange for repair/replacement, or, if you’ve contacted us directly, we will work quickly to reply to your email with instructions
4. If you have contacted Stan’s directly regarding crash replacement and your request has been approved you will be charged crash replacement pricing for your product and standard return shipping fees.

ALUMINUM RIM Warranty AND CRASH REPLACEMENT CONDITIONS:

1. Warranty and crash replacement are valid only for the original owner and are not transferrable.
2. Warranty does not cover the following:
   a. Damage sustained during shipment
   b. Products on which serial numbers, production lot codes/date codes or other identifying marks have been removed
   c. Normal wear and tear, misuse, incorrect installation or improper maintenance, use of incompatible parts or components, accident or crash damage, negligence, modifications not recommended or approved by Stan’s
   d. Labor costs for work not performed by Stan’s
   e. Shipping costs to Stan’s or local distributor
   f. Instances determined to be cosmetic only
   g. Any representation or Warranty expressed or implied by a third party beyond the provisions of this stated policy
   h. Purchases made through unauthorized resellers such as eBay, Alibaba, Amazon or similar resale sites
3. Crash replacement does not cover the following:
   a. Normal wear and tear expected with the use of high-quality mountain bike components
   b. Products on which the serial numbers, production lot codes or other identifying marks have been removed
   c. Misuse, incorrect installation or improper maintenance, use of incompatible parts or components, negligence, modifications not recommended or approved by Stan’s
   d. Instances determined to be cosmetic only
   e. Shipping costs to or from Stan’s or the local distributor
   f. Labor costs associated with removing the wheels and any associated components including but not limited to rotors, tires, cassette, computer magnets, etc. from the bicycle or wheel

M-PULSE HUB Warranty POLICY

M-PULSE 5-YEAR HUB Warranty:
Stan’s M-pulse hubs are covered by a 5-year Warranty against manufacturing defects. Warranty does not cover abuse, misuse, consequential damage resulting from lack of or improper maintenance, normal wear and tear, and improper installation. Warranties only apply to the original owner with valid sales receipt. If a product is found to be defective, a free repair or replacement will be provided at the sole discretion of Stan’s.

HUB Warranty PROCESS:

1. Retain a copy of the original proof of purchase (i.e. Itemized receipt or invoice)
2. Submit your claim via an authorized Stan’s dealer with your proof of purchase or contact us at Warranty@notubes.com with a description of your issue, a photo that helps illustrate the issue, and your proof of purchase
   Note: For Warranty and crash replacement inquires outside the United States, please contact your local dealer or distributor
3. The dealer will contact Stan’s or the local distributor and arrange for repair/replacement, or, if you’ve contacted us directly, we will work quickly to reply to your email with instructions
4. If you have contacted Stan’s directly regarding a wheelset Warranty, and your approved request requires a return, Stan’s will provide you with a shipping label for return, free labor for your wheel rebuild, and return shipping

HUB Warranty CONDITIONS:

1. Warranty is valid only for the original owner and is not transferrable.
2. Warranty does not cover the following:
   a. Damage sustained during shipment
   b. Products on which serial numbers, production lot codes/date codes or other identifying marks have been removed
   c. Normal wear and tear, misuse, incorrect installation or improper maintenance, use of incompatible parts or components, accident or crash damage, negligence, modifications not recommended or approved by Stan’s
   d. Labor costs for work not performed by Stan’s
   e. Shipping costs to Stan’s or local distributor
   f. Instances determined to be cosmetic only
   g. Any representation or Warranty expressed or implied by a third party beyond the provisions of this stated policy