The Shimano S-Phyre RC903 road shoes arrived hot on the heels of my S-Phyre RC902 test and have been my go-to road shoes this year. Riding the 903 and 902’s in back-to-back seasons, Having tested the 902’s in 2022, I was anxious to test the updated 903’s during the 2023 season. Now, after nearly 1000 miles over 6 months, it’s time to share how these shiny blue shoes have performed.
Shimano S-Phyre RC903 Road Shoes Features:
- Shimano’s premium road racing shoe, optimized for performance
- Compatible with 3-hole road cleats (SPD-SL, etc.)
- Precise fit using dual, low-profile BOA® Li2 dials
- Dynalast shape for expanded fit (wide last available)
- 360º surround wrapping upper
- Anti-twist heel cup for added stability
- Lightweight uppers with perforated vents for optimal cooling
- Added toe protection
- Stiffness index: 12 (Shimano’s highest)
- MSRP: $450

Podium-winning shoes evolved
Under the powerful feet of the world’s top cyclists, the Shimano S-Phyre RC903 shoes have reached the podium of just about every major event on the calendar. As Shimano’s top-tier racing shoe, all the materials, construction and fit aim at squeezing out every last millimeter of performance possible. As with the prior model, the wraparound uppers are unique to the market and provide a unified platform for comfort and power transfer. Due to that wraparound construction, the “outsole” isn’t completely visible, but it’s a stiff, carbon number that tops Shimano’s stiffness index.

The RC902’s were a fantastic road shoe, but the RC903’s add to them with enough niceties that further entrench them at the top of the road shoe world. Complementing the new upper design are the dual BOA Li2 dials. These offer micro adjustments in either direction and deliver smooth pressure and a near-custom fit all the way around each foot. The most noticeable update is the lacing pattern of the forefoot. Gone are plastic guides and instead, fabric guides are built into the uppers — adding an additional section over the previous model. In side-to-side tests, the differences between the old and new models are noticeable. In particular, the forefoot is more foot-cradling while being more comfortable at the same time.

Every little detail is thought out, down to the way the upper strap is guided across the tops of your feet. Micro-channels are built into the tongue, with corresponding channels on the underside of the strap. This ensures a proper fit and further locks in the fit. Adding to that, the heel cup is deeper and the materials are more refined to eliminate the need for the heel grips found in the RC902. The on/off experience is awesome, with the burrito wrap and dual Boa dials that open wide.
I have been testing the S-Phyre RC903’s with the Time Pro 12 pedals this year. And, while Shimano would certainly prefer a Shimano/Shimano interface, you are free to use whatever road pedals you prefer (last year, I successfully used the Wahoo POWRLINK Zero pedals). Cleat install is a breeze and they offer a wide adjustment range to ensure proper placement. With any new pair of shoes, keep your old ones mounted up to easily compare and match your existing cleat position. Or, just do one shoe at a time, if you’re re-using old cleats.

After hundreds of initial miles on the Stages SB20 Smart Bike, I hit the tarmac in earnest in May aboard the Fezzari Veyo SL. The RC903’s have turned out to be the perfect pairing with this fast and capable road bike as I’ve been able to push myself and the bike to its limits.
While extra-stiff road shoes can sometimes become uncomfortable on long rides, the combination of the foot-cradling uppers and wrap-around construction provides long-distance comfort not often found in a race shoe. Tackling the hour-long climb of Utah’s Alpine Loop is nothing but comfort in these shoes. Likewise, pedaling on long, rolling routes yields equal comfort. Not once have I experienced any pressure points or discomfort on long or short rides.

Not only are the uppers more foot-cradling than before, they are also more breathable as well — all those air vents and mesh inserts ensure great breathability. That winning combination certainly adds to the overall performance. As is the case with the BOA Fit System, it’s so easy to add or remove tension as your feet swell during a ride. And, it’s equally easy to modify the fit based on sock thickness. I’ve worn these successfully with ultrathin socks and thick winter socks alike. Airflow is a great attribute of the S-Phyre R903 and you can definitely feel it at speed. Adding to that, Shimano has a heel port for all water to work its way out if you’re ever caught in a storm.
While my regular-width feet and low arches are perfectly-comfortable with the regular width RC903’s, if you have wide feet or prefer added wiggle room, they do offer wide versions with an additional 3-4mm in width. In addition, the shoes come with arch supports to further customize your fit.
Fit: My size 10.5 feet are perfectly-suited in the size 45 RC903 and are on par with all Shimano shoes I’ve worn.
The Good:
- Stiff and responsive in and out of the saddle
- Foot-cradling uppers that contour every inch of your feet
- Locked-in heel cup
- Added breathability makes these even better in the summer heat
- Dual BOA Li2 dials for the ultimate adjustability
- Flashy color options add pop
The Bad:
- A little more toe protection for inevitable toe/tire overlap
The Bottom Line: Shimano S-Phyre RC903 Road Shoes
Wrapping things up (literally), the Shimano S-Phyre RC903’s continue Shimano’s long tradition of excellence with their top-level road shoes. Their ultra-stiff outsoles are matched up with some of the most comfortable uppers I’ve ever experienced that will improve your on-bike performance while sprinting, climbing or simply tackling an endless day in the saddle.
Buy Now: Available from CompetitiveCyclist