Sorry, RR stands for Rolling Resistance, measured in Watts needed to move the tire at a given speed, which Stu provided in the above post.
Resistances needed to overcome during riding: Wind Rolling Gravity (when not on a flat surface) Then there's also an impedance that comes into play when you hit bumps that slow your speed
I would also say give the Pathfinder Pro a serious look for a tire with a slick / semi slick center + small side knobs. Somehow they managed to make a tire that rolls very fast straight, has decent bite in corners, rides nice, has great puncture resistance, wears well, and is zero fuss tubeless setup, at the cost of some weight. Would be nice to see an even wider option for 700c, but I'm guessing with the supply chain issues, adding more options is probably not at the top of the list for distributors.
I'll add another tire; the Pirelli Cinturato Gravel H; it is available in 40mm. I have been riding 45's for several months and really like the way they feel which I take to be due to the casing. My gravel rides are all gravel but the roads vary from pretty smooth to some fairly rough sections. I've ridden them around after working on my bike and they are smooth and quiet on pavement; I think they would be fine for some extended pavement sections. For me they are the right balance of fast while still having grip on some loose stuff. I'm in Az so mostly loose over hard, no mud.
I also like the Cinturato Gravel H, at least in the 45 mm size I've used. On hard dirt it rolls well and feels stable. On pavement it's also fast and handles well. Compared to the GK+ (slick) and the Strada Bianca Pro it's heavy and doesn't feel as supple. The Cinturato runs somewhat large, on 25 mm (inside) rims I'd expect the 40 mm version to measure closer to 42 mm.
The Cinturato Gravel H is supposed to have excellent (low) rolling resistance, on par with the Pathfinder Pro. The only negative I can find (from research, haven't ridden it) is it sounds like it's puncture prone (this based on two reviewers I trust).
That being said, I run the Cinturato Gravel M's all winter, on all surfaces, even for my road riding, and absolutely love it. No punctures, nice and comfy, and when it snows or is icy they are amazing. Only downside is higher rolling resistance, but over the winter on training rides, I don't care. I throw knobby's and fenders on my gravel bike and use that set up for all outdoor winter rides regardless of surface.
I don't do gravel races, but if I did (and did less road) I'd be thinking about the GK-SK. I haven't used the Vittoria tire, but from the images the SK is a more direct comparison. I've used both SS and SK and for your purpose I wouldn't hesitate with the SK to avoid struggles if the FSR turns steep or you find yourself racing in the rain. But the SS is great too - I'm currently using them in 38, preceded by SKs in 42 and finding them a better compromise for my present mix of perhaps 80pc tarmac and 20pc FSR. I only wish I'd stuck with the SK when I hit snow, which is not a lot of the time.
I know your post wasn't comparing these two tires, but the conversation kind of went this so I figured I'd weigh in:
I've raced on both the 38 GKSS and the 42 Pathfinder Pro and ridden a few thousand miles on each.
For pavement, sure, the center strip is nice on the PP, but the SS is faster by far. No contest. You will lose a chunk of time running the PP (especially the 42) if the race has a lot of pavement.
On dirt, from my POV, the PP is far superior to the SS (and this is coming from someone who likes the SS a lot). Sure, the SS is lighter so it can be faster in perfect conditions, but if the road is rocky/rutted at all the PP42 will plow over stuff that I find myself navigating around on the SS38. Each of those turns/maneuvers costs time that all adds up. And on downhill dirt that effect is magnified. You'll save yourself a lot of time with the PP if your race has a lot of dh dirt.
For me, your call kind of comes down to race length (apologies if I missed it in your post) and quantity of pavement. Typically, if a race or ride is over 75 miles and 80% dirt I'm going to run the PP42. If it's under 75 miles and features a lot of pavement (especially in segments crucial to the race outcome), I'll go with the GKSS.
mtgrvl wrote: For me, your call kind of comes down to race length (apologies if I missed it in your post) and quantity of pavement. Typically, if a race or ride is over 75 miles and 80% dirt I'm going to run the PP42. If it's under 75 miles and features a lot of pavement (especially in segments crucial to the race outcome), I'll go with the GKSS.
The event in question is the Montana Gravel Challenge. 56 miles. 50/50 gravel/pavement. You going?? We did the Rocky Mountain Roubaix last year and it rained towards the end. I rode GK SS's. They were fantastic on pavement. Excellent on hardpack gravel. But a bit squirmy once it got wet/muddy, hence one of the reasons I'm looking for something with a bit more "bite". There is enough gravel on this race that I want confidence in descending.
I bought a set of Terrenos for my wife's bike and Kenda Alluvium Pros for mine to try once the roads clear up. If those don't measure up then I plan to try the Pirelli Cinturato Gravel H and the Pathfinder Pro.
Nice! I won't be able to do all 3 days, but want to register for either Saturday or Sunday if it's not snowing/still good skiing that weekend. Sounds like you chose some great tires to try out! I'm tempted to give the Cinturato H a try this year too.
Got out for the first pavement ride of 2022 this weekend. I rode my Warbird on the 700x40c Alluvium Pro's and my wife was on her Bombtrack and 700x38c Torreno Dry's. The Alluviums are super comfy on broken pavement. I ran them at 50r/40f (220 lbs. kitted). I'd run them lower for gravel, but this was one of the rubs on this tire. Very hard to find a pressure that works well for both. They felt a little slow on the climbs and not super spunky on the flats. Data analysis when I got home shows that they give up quite a few watts on the climbs to the 700x38c GK+ slicks we usually ride on the pavement. Not so bad on flat pavement. My wife on the other hand, rode away from me on the climbs well.... she IS about 60% my weight 😆), and when looking at her data, the Torreno Drys appear not to give up much, if anything to the GK+ Slick. I will use the Alluvium for a training tire this spring. They handled mixed conditions very well, but I wouldn't want to use them on a 60 mile race that is half pavement.
thumper88 wrote:I have never understood why someone would ride terrenos, dry or otherwise. They have never tested fast and ... go back and read how Taylor Phinney’s Kanza attempt worked.
At this years Worlds, almost everyone was on a Terreno Dry, sponsored or not.
OP here.... double follow up post. We have now run the MGC Southside race 2 years running and used data from last year to make better decisions. Both years we ran the Vittoria Torreno Dry 700 x 38c in front and the GK SS 700 x 38c rear. Everything else the same. The big difference is that last year we rode on a compromise tire pressure. For me, 210 lbs. kitted, that was about 44 lbs. THIS year I ran 50 lbs. f/r for the pavement at the beginning and then dropped to 34f/38r for the gravel. The tires were noticeably faster in both conditions and the speed/watt was higher. In addition the confidence level on the sketchy gravel descents was much higher. I took 33 minutes off of last years time. A little of that is tires, some knowing more what to expect and where I could push, the rest is fitness.
For 50/50 conditions this combo is really hard to beat.
