Skip the drag, and coast with ease! Stan’s newest innovation in bicycle hubs combines top-notch materials with a smart, magnet-driven, engagement system. M-pulse hubs have been reengineered from the ground up to have you rolling smoother, longer.
With Stan’s patented, BST-Asymmetric shape you can expect a top-of-the-line, reliable tubeless seal. While the durable 6069 alloy construction and reinforced spoke bed, combine to create an incredibly durable wheelset that builds confidence with every ride. Built with strength and easy serviceability in mind, the asymmetric rim allows for a single spoke length on both the front and rear wheels. Using traditional J-bend spokes and lacing for proven strength, ride quality, and serviceability for the life of each wheel.
A Magnetic Heart
What really set’s Stan’s Flow MK4 wheelset apart from the crowd is the new, magnetic engaged M-Pulse hubs. Featuring an innovative and bombproof magnetic locking engagement system that provides an unbeatable smooth-rolling, no-drag ride. Unlike weaker pawl and spring designs, the M-pulse features six pawls with Neodymium magnets that offer virtually no resistance when coasting, and reliably lock into place quicker than standard spring-based pawls.
The heart of M-pulse hubs is the magnetic-locking engagement system based on the ground-breaking Project321 design. Manufactured in a small-batch, high-precision facility in Bend, Oregon, M-pulse freehubs feature six pawls equipped with Neodymium magnets engaging every 1.66°. This design offers substantially more force than traditional spring-based pawl designs, and costs you much less drag when coasting. With decreased friction, Stan’s new M-pulse hubs spin more freely than any other hub on the market, and roll further, faster, with less effort, too.
Stan’s believes an innovative design is only as good as its materials and construction. So each detail of the M-pulse hub has been engineered to remove the weaknesses in traditional pawl and ratchet-style hubs.
Built to Last
Featuring 17mm axles, made of 7075 aluminum, rolling on long-lasting Enduro-brand bearings, plus a custom grease fill - Stan’s has taken every effort to optimize for low resistance and high durability.
Carefully engineered to eliminate weaknesses found in other hub designs, the hub is fully shielded, with no visible bearing seals, giving you superior protection when riding in any conditions. With just 1.66° of rotation needed to engage the M-Pulse hub, power is always there right when you need it!
M-pulse hubs also feature an adjustable preload that decreases drag and resistance for even less effort and more speed. This preload prolongs bearing life by allowing the hub's bearing tension to be tuned with greater precision. 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 exactly what you’d want.
Tubeless-ready with rim tape and presta valve installed.
Stan’s original Flow redefined what you could expect a mountain bike rim to do. And now, the Flow MK4 gives you the power to do even more!
- Flow MK4 wheels include pre-installed tape for tubeless use and Presta valves.
- Low-profile 30mm internal width. Offering optimal 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
Matching front wheel: Stan's No Tubes Flow MK4 front wheel
Rear Hub: Stan's/Project 321 M-Pulse hub
- Rotor: 6-bolt
- Hub spacing: Boost (12 x 148mm), SuperBoost (12 x 157mm)
- Freehub: Shimano HG, Shimano Micro Spline, SRAM XDR (SRAM XD with included spacer)
- Points of engagement: 216
Rim: Stan's Flow MK4
- Rim Size: 27.5", 29"
- Material: 6069 Aluminum Alloy
- Hole: 32h
- Internal width: 30.0mm
- External width: 33.6mm
- Tire width: 2.3 - 2.6"
- Sapim D-Light, 2.0/1.65/2.0
- # of spokes: 32
- Sapim double square alloy nipples
- Wheelset: 1792g (27.5"), 1882g (29")
- Rear wheel: 972g (27.5") / 1017g (29")
Please reach out to us with any questions you may have on anything we sell. We want to make sure you get the right part the first time. Our lifelong riders at Thunder Mountain Bikes are knowledgeable and would love to talk to you!
We currently offer both economy and expedited shipping options though FedEX and USPS.
Orders totaling over $49 are eligible to ship for free via an economy ground option of our choice.
If you're in need of something super-quick, please contact us directly. We may be able to overnight your order with an additional fee and depending on your location.
Should there be an issue with the item you bought, or you no longer need your purchase, we will be happy to set up a return.
All returns must be requested within sixty (60) days of the fulfillment date (i.e. the date we printed the shipping label and boxed up your order.) All returned items must be received in new and unused condition, with the original tags and labels attached, and in the original packaging. We cannot accept returns on any items that have been installed or show wear of any kind.
To request a return, please visit: returns.thundermountainbikes.com and follow the steps to return eligible items from your order.
After receiving your return and inspecting the condition of your item, we will process your return. Please allow at least seven (7) days from the receipt of your item to process your return or exchange. We will notify you by email when your return has been processed.
For all Special Order items, there is a 25% restocking fee. Special Order items are those that we do not currently stock.
For defective, damaged, or if we sent you the wrong products, please contact us using the phone number or email below.
If you have any questions concerning our return policy, please contact us at:
ThundMtn shipped supafast and the wheel is so beautiful and exactly what I have dreamed about having in a box in my living room. I cannot vait to put it on my new ride!!!! Heard so many great things about this hub and wheel and I love Stans. Great products that they are always improving and just super nice customer service forever. Thank you.
Built up a Hardtail bike. Wanted to find a rear wheel with a high-engagement hub, that would perform similar to industry nine hubs. Well, did I ever. The Engagement is extremely high on this hub at 1.66°. There is virtually zero slack/play when starting your pedal stroke. I purchased this wheel when it was on sale, but even at its regular price, this is an incredible deal. No regrets. Lastly, thunder Mountain shipped everything quickly and efficiently. (Plus the sound is amazing) Arrived with incredibly sturdy packaging, and as an added bonus I get another sticker to add to my collection. 👍🏼 Long story short, just buy this wheel/hub combo. You will love it!