Ibis

S28 29in I9 Carbon Boost Wheelset

The S28 29in I9 Carbon Boost Wheelset from Ibis is a story about three companies. Stan’s NoTubes was one of the first companies to pioneer the modern tubeless system over 20 years ago and continues to innovate rim technology to this day. Ibis has been at the forefront of wide rim widths for many years, reaping all of the benefits while the rest of the industry has been playing catch up. Lastly, Industry Nine continues to whittle away aluminum into some of the quickest engaging, reliable, and beautiful hubs on the market and lead the pack with its newest Hydra hubs. So when Ibis decided to redesign its wheels and began development on the S-Wheels lineup, it employed Stan's patented Bead Socket Technology (BST) into its wide, asymmetric carbon fiber rims and laced them to the venerable I9 hubs to create some of the lightest, strongest, and best-performing wheels available.

Stan's BST allows Ibis to reduce the rim's depth, down to 18mm, which makes the rims more vertically compliant. This helps improve the ride quality and better distributes impacts while also providing EWS-level performance at incredibly low weights. Additionally, the new carbon S rims are 9% better at resisting impacts than the already tough rims while coming in at even lighter weights.

The "toughened” carbon has just the ideal blend of resin and carbon that allows Ibis to achieve just the right layup it's after for both feel and strength. Part of this secret formula is the toughened resin in the beadwall that doesn't flinch when facing hard impacts. It further supplements the bead walls with carbon using a stiffer resin to ensure they hold their shape.

As we mentioned above, Ibis discovered the benefits of wide rims over half a decade ago. This sparked an industry "wide" revolution and helped usher in the current crop of 2.4 to 2.6-inch tires that are so popular today. The S28's sit at 28mm wide internally and 35mm externally, allowing the tire beads to splay further apart. That wider footprint provides way better tire sidewall support, meaning you can run lower air pressure and also creates a larger contact patch. This is advantageous on many fronts including an improvement in traction, braking control, and reducing rolling resistance over rough terrain, while also nearly eliminating the possibility of burping.

Ibis builds its rims with an asymmetric offset. It does so because it improves the bracing angle of the spokes. And because the rims are so wide, Ibis is able to make them even more offset than normal. This offset allows Ibis to more evenly tension both sides of the wheel for a stronger and more durable wheelset.

Something else we've really come to appreciate with Ibis wheels is that it's built up with readily available components, so sourcing replacement parts at races and while on vacation aren't too difficult. Standard J-bend spokes and external square nipples make the wheels easy to service and for finding spare parts in the field. And should something happen, Ibis backs its rims with a seven-year warranty against defects and a low cost “accident replacement” program that covers just about everything else.