Description
The Backbone is a bomber
The Backbone is an extremely rugged 27.5" mountain bike rim with a particularly wide internal width of 32mm. Like other models where durability is important, it uses an asymmetrical rim design that improves spoke tension balance by up to 30%, increasing wheel stiffness, strength, and longevity.
For general trail use, the rim profile of this backbone is interpreted as the most reliable and balanced construction, especially with the 32mm inner width, which makes it compatible with many trail tires.
[SPEC]
| Material : Aluminum | Aluminum |
| Size : 650b | 650b |
| ETRTO : 584 | 584 |
| Hole : 28H, 32H | 28H, 32H |
| Height : 20.0mm | 20.0mm |
| Width : Inner 32.0mm, Outer 36.0mm | Inner 32.0mm, Outer 36.0mm |
| Optimal Tire Width : 55mm - 76mm | 55mm - 76mm |
| Tire Interface : Clincher / Tubeless Ready | Clincher / Tubeless Ready |
| Weight : 535g | 535g |
Disc Brake Only
[SIZE]
| ERD : 561.5mm | 561.5mm |
| Spoke Bed Diameter : 559mm | 559mm |
| Max Tension : 130kgf | 130kgf |
- Orders are shipped within 1–2 business days after payment is confirmed. Orders placed by 10:00 AM are generally shipped the same day.
- Messenger delivery is available within Nagoya City only (excluding complete bikes and framesets).
- We ship every day from Monday through Sunday, except on temporary closure days.
- Shipping destinations: throughout Japan and worldwide.
- Shipment may be delayed depending on credit card processing. If you would like to request a delivery date or time, please add a note in your cart.
- All orders are shipped from Circles.
- For damage or loss during transit, please contact the carrier.
Complete Bike Shipping within Japan
- A shipping fee of ¥9,900 (tax included) applies to complete bikes. Additional charges may apply for Okinawa and remote islands.
- After purchase, we perform a final inspection before shipping. Please allow 1–2 weeks in some cases.
- For packing, some parts may be removed. We strongly recommend having the bike reassembled and checked by your local bicycle shop before riding.
- We will contact you by email with delivery details.
- Products are also sold in-store, so availability may change before the order is finalized.
Frameset Shipping within Japan
- Flat-rate shipping within Japan: ¥5,500 (tax included). Additional charges may apply for Okinawa and remote islands.
- Shipping rates for OMNIUM framesets and complete bikes differ.
- We will contact you by email with delivery details.
- Facing and tapping preparation for framesets purchased from Circles is available at no additional charge. Details will be provided after purchase.
- Headset and bottom bracket installation are also available for an additional labor fee. Please contact us if required.
Custom & Stock Wheel Shipping within Japan
- A shipping fee of ¥2,000 (tax included) applies. Additional charges may apply for Okinawa and remote islands.
- Stock wheels undergo a final inspection by a mechanic before shipping. Please allow approximately 3 business days for dispatch.
For international orders, shipping costs vary by destination. Please check the amount shown at checkout.