- In stock, ready to ship
- Free shipping on all orders $59+
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
Details:
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"
Spoke:
- Sapim D-Light, 2.0/1.65/2.0
- # of spokes: 32
- Sapim double square alloy nipples
Weight:
- 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 items the first time. Our lifelong riders at Thunder Mountain Bikes are knowledgeable and would love to talk to you!
Shipping
We currently offer both economy and expedited shipping options though FedEX and USPS.
Orders totaling over $59 are eligible to ship for free via an economy ground option of our choice.
Most bikes ship free within the continental US. Bike shipping to AK, HI, or PR is $250.
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.
RETURNS
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.
Component & Gear Returns
Returns may be requested within sixty (60) days of the delivery date. All returned items must be received in new, unused, and uninstalled condition, with the original tags and labels attached and in the original packaging. We cannot accept returns on any items installed or show wear of any kind.
Bike Returns
Returns or exchange requests for bikes must be requested by emailing us at sedona@thundermountainbikes.com within fifteen (15) days from the date of delivery. Bikes must be in un-ridden condition. Custom-built bikes may not be returned. Returned bikes have a $200 restocking fee and the customer pays for return shipping.
Return Shipping
Customers may choose to use our provided flat-rate return shipping label at $9, or choose a carrier of their choice to handle their product return.
The $9 flat rate label will be deducted from the refund issued for the return. You can either print this label after requesting a return from the Order History in your Account profile, or you can request that we email you the label.
For all other return shipping methods, please email us at sedona@thundermountainbikes.com after submitting your return request so that we can confirm the shipping information you should use to return your item(s).
REFUNDS
We will process your return after we receive your returned item(s) and inspect the condition. Please allow at least seven (7) days from the receipt of your item to process your refund. We will notify you by email when your return has been processed.
EXCEPTIONS
If you receive defective or damaged products or if we sent you the wrong products, please contact us using the phone number or email below.
RETURN PROCESS
To request a return, please log in to your customer account by clicking the 
Profile icon in the top right of any page or visit account.thundermountainbikes.com.
1. In the Email field, enter your email address and click Continue.
2. In your email account, open the email sent from our store and copy the six-digit verification code included in the email.
3. Go back to the online store and enter a six-digit verification code to log in.
4. Find and click on the order that you want to submit a return for.
5. If your order has more than one item, select only the items you want to return.
6. Select a return reason and add a note for the store if needed.
7. Click Request Return.
Once your return request is approved, you will receive an email with shipping instructions and a return shipping label.
QUESTIONS ABOUT RETURNS?
If you have any questions concerning our return policy, please contact us at:
