27.5" vs. 29" Wheels for the Orox S12 E-Cargo Bike: How to Choose

27.5" vs. 29" Wheels for the Tern Orox S12 Cargo eBike: How to Choose

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If you’re considering purchasing the Tern Orox S12 e-cargo bike, you may have noticed that it's available in two wheel sizes (27.5” and 29”). And if you already own an Orox S12, you might be thinking of the advantages of switching sizes.

The Orox wheelsets, named the Atlas X27.5 and Atlas X29, each offer unique advantages in different conditions, so your choice should align with your needs and preferences to ensure optimal performance. This article explains each wheel size’s characteristics, highlights their similarities and differences, and discusses why you should choose one over the other (or both!).

Contents


What are the Atlas X27.5 and Atlas X29 Wheelsets?

The Atlas X27.5 and Atlas X29 Wheelsets correspond to 27.5 and 29-inch wheelsets for your Tern Orox ebike. They comprise bespoke rims, hubs, spokes, and other high-quality components for the Orox to overcome tough off-roading conditions while keeping you safe and stable during the ride. If you’ve bought one wheel size along with the bike, you still have the option to get the other size following your purchase.

TN_atlasx275_front_34_web.png
TN-Atlas X29-front-side.jpg

Atlas X27.5 Front/Rear Wheelset

Atlas X29 Front/Rear Wheelset

Think of anything that might come across your path, such as steep inclines, thick tree roots, rocks, or even shallow streams. There’s not much the Atlas X Wheelsets cannot handle, and yes, this includes off-roading maneuvers and transporting heavy cargo and passengers. Rest assured, the wheelsets are engineered to withstand the Orox's 210 kg (463 lb) on-road or 180 kg (397 lb) off-road MGVW!


What are the similarities between the Atlas X Wheelsets?

Both wheelsets’ durability is made possible by these high-quality components:

  • Double-walled aluminum Atlas X rims that tackle demanding terrain and provide stability as you carry stuff and fellow adventurers.
  • Custom Atlas hubs enhance stiffness for heavy loads on unpredictable terrain, plus a custom freehub body with sealed bearings for resistance against impact forces.
  • Integrated disc cooling fins for reliable and consistent braking in all conditions, which is crucial for long descents.
  • Both wheelsets can accommodate various tire types—studded tires for the winter, slicker tires for city cruising, or knobby tires for off-roading.

If you're choosing an Orox

The Atlas X27.5 Wheelset is compatible with 27.5” x 4.0” tires, many of which are designed for enhanced traction. The 4.0” width is ideal for increasing ground contact on loose surfaces like gravel, snow, or ice. Due to their ability to run at lower tire pressures, fatter tires can offer better suspension and shock absorption for a smoother ride.

Compared to the Atlas X27.5 Wheelset, the Atlas X29 accommodates any 29” x 2.6” tires and is a more nimble and lighter alternative. Its slimmer tire profile is more suitable for reduced weight, improves acceleration, and helps to extend your battery’s life. In other words, the 29-inch wheels offer quicker and easier handling for greater agility.


If you already have an Orox

If you already have an Orox S12, don’t worry—the 27.5” and 29” are available in the aftermarket, depending on your region. Each wheel excels in specific conditions; your decision will also depend on how and where you will ride your Orox.

If you often find yourself riding on loose surfaces such as gravel and want that added grip on snow and ice in the winter months, we recommend getting the Atlas X27.5. The wider tires provide added stability when navigating inclines, giving you greater security during ascents and descents.

If you’d like to ride your Orox more frequently on paved roads or otherwise less bumpy paths, then we’d recommend the Atlas X29. The Atlas X29 can also still help you manage significant loads, but with a smaller surface contact area for reduced drag.

For versatile use, you could invest in both wheel sizes and swap between them for maximum utility on and off the road!

For more information (and if you like DIY), we also have an article on how to install the Atlas X wheelsets on the Orox S12.

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