I've used various tires over the past 9 years for gravel and have since switched over to mountain bike XC tires for most of my gravel needs as they are simply superior in pretty much every way. However, I wanted to try these tires out (along with the G-One R in 45mm which I'm less impressed with), so I grabbed a pair of these in 50mm. The RX's are very fast in a straight line. I'd put them on par with my Race King 2.0's on the straights.....however, for my terrain (Sonoran desert single and double track with varying degrees of sand over caliche and rock), the Race Kings/XC tires grip far better in the turns than gravel tires do. Now, if you're mostly going in a straight line and the terrain isn't too technical/chunky/demanding (think something like BWR Utah, which I would definitely use these RX's on) and your frame maxes out with 50mm tires, these tires would be a good option. Got them on the rim very easily, although I had to use an air compressor to get one of them to seat......easy peasy with the Park inflator head, my single best tubeless upgrade/tool. The QC at Schwalbe could be improved though as one tire weighed in at 630 grams and the other was 670 grams. Not sure why there was such a large discrepancy. They ride and roll well though, very comfortable. They don't have the cornering confidence of my Race Kings, but "gravel" tires are generally always a performance tradeoff trying to balance pavement and gravel/dirt road performance. When I'm blasting through non-technical singletrack with cacti lining both sides of the trail, cornering grip becomes exponentially important as running into a cactus (especially cholla) sucks a lot. If you're lucky enough to have dirt trails and no real consequences for sliding out in turns where you live, the cornering grip will probably be halfway decent for a gravel tire. They are a bit on the pricey side though, would be a good deal if they were about $25 less expensive.
I got the 50s for my gravel bike to soften the ride and provide more traction over tech. Previously I had the same tires in 40. I definitely notice the improvement in ride going over square edges. As for the tires themselves I've done 50+ mile road and gravel rides and they're great. I primarily ride on San Diego asphalt and offroad in the Lake Hodges area.
I'm running the 50s on a stock Trek Checkpoint SL5 2023 and they clear all the tight points. Trek says the max tire for the bike is 45 so keep that in mind. You can hit the tire with your forward foot in tight turns, but that also happened to me with the 40s. Obviously your clearance between the tire and frame is reduced so keep that in mind for clearing mud/debris.
As for the value, at $91 a pop these are getting up there, but that's right where I would expect a newer tire that seems to have a marketing push and actual professional race success behind it.
With more Gravel riding under my belt this year, I realized that having an alternative location for shifting would be helpful, for comfort and for aero riding on the tarmac or smoother trails. Adding them to the crossbar, fairly close to the stem, was a great solution. After 5 days of gravel riding in Kansas, I realized just how wonderful they were. The only hard part was wrapping the handlebar tape around them to hold them in place and keep the wrap relatively smooth. The neighborhood bike store was very helpful in doing that as they wrap handlebars frequently.
This really is a good looking bar, I was super excited when it came it and thought it would work great. I'm a fan of a shallow drop for a gravel bar as well. The bar looks and feels premium.
Cable routing is excellent but that also leads to the first quirk, the grooves for cables run up into the stem clamping area. There are explicit warning marks (which are not shown in the pictures here) where you stem must clamp and they're fairly wide. I tried my stock OEM Cervelo stem and the clamping area was too narrow. Same with a Zipp, FSA and Ritchey stem I had laying around. Also, the cable routing grooves dictate how much you can rotate the bars in the stem. This wasn't a problem for me but if you wanted your bars pointed fairly upwards for some reason, the manual says don't do that.
Okay fine, I'll buy the matching Pro Discover stem. That...kinda meets the minimum clamping area criteria. It's pretty close and I wonder if Pro designed this to be used with their aero stem and no others.
Setting up the bar, I put the shifters up where the shifter clamp just touches the highest clamping mark on the bars. When I ride I have my forearms pretty flat and like the shifters to be a little more upright. Well at this position, the shifters are pretty close to flat. I really don't know what most of the rest of the marked clamping range would look like - shifters horizontal or pointing downwards?
On top of this, at the highest point where I have the shifters installed, there's a gap between the GRX shifter body and the wide part of the bar it's supposed to match up to. I guess it makes sense they couldn't really overlap and the hood covers it, but now the feel of the bar is a slight bump/rise as you get near the hoods, then a divot where you're on the round part of the bar and then the body of the shifter.
Personally this is a one star but I gave it three because maybe it's just me as the other two reviews seem very positive. But the setup ergonomics of this bar just seem strange. And the fact that you need a stem with a wide faceplate is a pain. I also can't find that stem clamping area requirement mentioned on Pro's website or in any of the "professional" reviews I read before purchasing it.
