Stans NoTubes Arch MK4 6-Bolt 27.5 15×110 63.5 Front MTB Wheel

The Arch MK4 is the wheelset a lot of us here at Stan’s choose to ride. All-mountain, Downcountry, Trailduro—whatever they’re calling it this week when you like pushing your limits on climbs, descents, and every kind of trail, this is your wheelset.

The Arch MK4’s 28mm internal width and patented lightweight, low-profile design is not afraid to climb while being an absolute monster on the descents. With a welded seam, reinforced spoke bed, and durable 6069 aluminium construction, the Arch MK4 rims give you the confidence to ride everything. When it comes to a consistent and reliable airtight tubeless seal, nothing beats Stan’s patented Bead Socket Technology. The Arch MK4 rims feature an asymmetric design with offset spoke holes to improve the spoke angle and create a stronger all-around wheel. Unlike most asymmetric rims that suffer from difficult inflation and poor tubeless performance, Stan’s BST-Asymmetric design delivers all the advantages of a stronger wheel, with no compromises in tubeless performance. Nobody likes downtime, so the Arch MK4 wheelset is built with traditional J-bend spokes based on their proven strength, ride quality, and easy serviceability. Stan’s has always made it easy to find replacement spokes should you ever damage your wheel, and now we’ve made it even easier. MK4 front and rear wheels of the same diameter all use the exact same very common spoke length, both sides, front and rear. Serviceability doesn’t get any easier than that.

From the first click of the incredible M-pulse hubs, it’s clear that confidence is the philosophy behind every part of this wheelset. Designed and CNC machined by Project321 in Bend, Oregon, M-pulse freehubs feature 6 pawls with Neodymium magnets that lock into place with greater force than conventional pawl springs but offer virtually no resistance when coasting. Multiple teeth on each pawl offer better load distribution for years of trouble-free riding, and the angle of the pawls was engineered to transfer stress away from the rotating bearings, decreasing stress and wear on the entire freehub. That durability extends to the 17mm axles machined of 7075 aluminium and the full complement of Enduro brand bearings, including a double-row freehub bearing. M-pulse internals is also fully shielded inside the hub because the only thing better than a good bearing seal is a good bearing seal most dirt can’t even reach. As durable as they are, these hubs are also built for speed. M-pulse hubs engage with only 1.66°of rotation, putting down power nearly instantaneously, but how smooth these hubs roll is what really stands out. Adjustable preload allows you to fine-tune M-pulse hubs for reduced friction, and less drag means more speed on the ground. The result is a bombproof hub with quick, consistent engagement and less resistance for more speed.

Key Features:

• Versatile 28mm internal rim width optimized for 2.2-2.5” tires
• Light and durable 6069 aluminium with a welded joint and reinforced spoke bed
• The 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