Until the release of the RX8 gravel shoe, Shimano’s offerings for the off-road roadie up have come direct from its cross-country mountain bike stable, topped by the brilliant but expensive S-Phyre XC9 (£319.99).
The S-Phyres are light at 754g (pair size 45), but the RX8s better that by some margin, weighing a claimed 628g (pair size 45). But just how has Shimano shaved over 100g from its premium off-road shoe and for a cheaper price?
Well the short answer is that it’s stripped down the elements of an off-road shoe and combined it with the lightweight PU upper of a road shoe.
The upper is constructed in one piece with a single offset seam at the heel. The upper is perforated for breathability and finished in a multi-coloured silver camo finish, with reflectivity built in for the multi-day adventure riders to be seen in the dark.
The closure is from a single BOA IP1 dial and a short Velcro strap across the forefoot. The fit is road shoe close and the Silvardur insole is anti-bacterially treated to keep whiffs at bay.
The insole comes with standard and high instep inserts to tune the fit, too.
The sole is where most of the weight has been trimmed, and the carbon sole is rated 10 out of 12 (compared to 12 on S-Phyres) for a little more give.
The sole has TPU rubber grip sections on the heel and around the cleat plate, and instead of the usual stud mounts up on the toe, the RX8s have a substantial rubber bumper around the toe with a thicker centre section.
This is designed to enable you to put your toe down without scuffing the front of your shoes, which is a neat idea and part of the feedback Shimano received from the collective of gravel riders it involved with the development of the gravel-specific GRX groupset and Shimano and PRO’s new line of gravel clothing and accessories.
On the bike, the RX8s are quite simply superb. The lightness makes them feel like a road shoe and the sole is stiff without being unforgiving.
For the sections where you may have to walk or run, the flex in the sole is forward of the cleat plate, just behind your toes, so even running in the RX8s feels more natural than a standard cross-country shoe (such as the S-Phyre).
The upper is close-fitting and plenty breathable, and the amount of adjustment afforded by the BOA is spot-on.
The toe strap is well placed and didn’t create a crease with my feet, though it might if you have a narrower foot shape.
The bonded rubber grips on the outsole work well and provide purchase even in the mud, the downside is the soft durometer of the rubber that makes it so grippy is showing proper signs of wear after a few 100 miles.
As these are non-replaceable that’s a bit of a concern, especially if you walk on tarmac in them or similar hard surfaces a lot.