I got some new wheels and am looking for some new tires to complement them. ~45mm. I’m not racing and most rides are 50/50 road/off-road. Off road is loose over hard of various depths, and front tire washout is the concern. So, I’m thinking a smooth-ish center section for road and low rolling resistance, and some nice big side knobs for the loose over hard. I’m currently on Schwalbe G-One Overland tires, which seem OK, but maybe something with smoother center and bigger side knobs. Any suggestions? Some I’m looking at are : Schwalbe G-One RS. Schwalbe G-One Ultrabite. Pirelli Cinturato Gravel RC. WTB Raddler.
I’ve used the Vittoria Terreno T30 in those kinds of conditions with good results. I’m about try a Hutchinson Caracal Race and see how that goes. Will report back here
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Smooth/slick center section does not necessarily equate to low rolling resistance. Rolling resistance is more about the casing/compound rather than the tread pattern. Some MTB tires like the Schwalbe Thunderburt and Conti Race King have lower rolling resistance than most gravel slicks (but they tend to wear faster on the road). In my experience, the smooth center gravel tires with some knobs on the sides don’t do any better on loose over hard compared to a pure slick. You just can’t lean a gravel bike over far enough on a tight/loose/flat corner to really engage the side knobs. The side knobs help in many situations, just not loose over hard in corners. Or maybe I just don’t know how to handle a gravel bike…. When I want to prioritize front tire grip off road, I run something with knobs over the entire tread. And I spend a lot of time on the road running knobby tires, it’s not a speed issue as much as a wear issue. And knobby treads obviously have less grip on the road vs. a slick, but I’m not pushing corners hard on the road.
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About to try the Caracal Race 45 as well… but the OP is not racing. Not sure I would run that if not racing.
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Great comment. It seems a little complicated to me. Compared to smooth tread, knobs deform the casing more and they themselves squish more when rolling, so I think losses due to hysteresis can be greater with knobs, all else being equal. Anyway, right now I’m leaning toward the Teravail Rutland, a tire I didn’t include in my original post.
I do like to corner aggressively on all surfaces. Staying within the limits of traction over varying conditions is the tricky part. I like the wide soft gravel tires for corning on pavement. They’re def more confidence inspiring than skittish 26mm road tires. A switch to a Maxxis Minnion DHR on the front of my mtb has made a big difference as well saving my bacon on a good number of occasions.
I ride mainly mtb, gravel, and very seldom my road bike. I don’t change tires until they’re pretty much worn out, and spread over three bikes, it’s pretty seldom. When I do get new tires I’m comparing them to old worn out tires, so it’s not really a legit comparison. (true for car tires as well).
It’s true, casing and compound matter more, unless you’re running monster enduro/downhill/mud tires. Rene Herse showed their knobbies run as fast as their slicks.
Joe
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Personally, I don’t run anything with tall center knobs, especially with a 50/50 pavement/dirt split. Maybe like 10/90 or even 5/95? Tread squirm makes for a poor pavement experience.
I run primarily Conti Terra Speeds in 90% of my gravel activities, it’s just knobby enough to tackle most conditions, but still rolls fast on pavement. Caveat is tread life is poor, which probably doesn’t excite you as a non-racer.
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Rene Herse how “shown” quite a few things that strain belief. Unfortunately, even the finest artisan time-keeping wasn’t enough for their testing to reliably produce such a result. Rene Herse (the company) made this statement many times, and had been taken to task for failing to provide evidence for many years. When they finally did, it was about what everyone expected, the knob tires were slower. Note that for the test, endurance casing was chosen in an attempt to minimize the difference between the tires.
All other things equal, more rubber is slower. Also the reason the newest Corkscrew climb is so relatively slow. CRR cannot be held constant, when everything else remains equal, except 40% of the surface is covered by 3mm tread blocks. Rubber compound, casing, or overall construction need to change to decrease CRR by the same amount the additional rubber has increased.
The BRR EL & TC tests of the Hurricane Ridge v. Snoqualmie Pass show how much of an effect the knob rubber has on the drum-calculated CRR. The Hurricane Ridge EL shows only a 2% decrease in CRR compared TC version. Contrast the Snoqualmie Pass EL with a 20% decrease.
Ardent Rene Herse fans will note the graph below which was published in the print edition of Bicycle Quarterly, has apparently never appeared on the Rene Herse website, instead a much more amenable test result was found and published there. There’s often been a disconnect between the long-form print testing and the short-form website testing, reasons as to why can be left up to the reader to determine.
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Wow. Lot’s of great input and discussion. I guess for my purposes, the priorities would be handling characteristics and cornering traction rather than speed. On my rides, I won’t notice if the tires are slightly faster or slower. There is a huge number of tires out there to choose among. And there are a lot of reviews, but few with direct comparisons, and the characteristics important to me are subjective anyway. For the time being, I’ll just swap over my existing tires over to the new wheels. That’ll keep one big variable the same while I’m evaluating the new wheels. But I will be getting new tires in the near future so please keep the discussion and recommendations going.
My guess is that RH would take issue with drum tests in general, noting that traditional drums are convex, which is very different than what we ride on.
On the other hand, it was drum tests that used to indicate that 19mm tires were faster, so clearly something has changed with testing methodology. Does anyone have the cliff notes version of why drum testing is giving better results now?
I’ve only seen the roll down data chart not the other one….where did that come from? I’m genuinely curious….im not familiar with problems with their testing.
Joe
@Saddlesaur I have Maxxis Ramblers in 45mm. Love them - actually rode the same tires twice for the Vermont Overland and have used them for all of my gravel riding this year and have no complaints. I bought some Vittoria Terreno T50s to replace them just to check out something else but still have the Ramblers on my bike and rode on them yesterday. They are not fast on pavement but what you lose there you will gain in handling and durability.
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This is not correct. The bulk of testing that produced these results were rolldown and weighted sled tests performed on flat surfaces.
Drum tests came later and I’m not certain 19mm tires were still around when they became common. The other issue, 19mm tires were within the statistical range to be as fast as 20-23mm tires that were common at the time. Racing-type tires were generally not made in larger sizes and CRR increased dramatically as tires became larger due to how they were constructed.
Much of the “data” around 19mm tires came from real world testing by euro pros and their coaches. Bernard Hinault devotes a few paragraphs to discussing how they tested tires in one of his books. It’s not rigorous but did produce results.
Otherwise, it has been known for some time that drum tests are a reasonable proxy to real world testing as far as relative CRR between tires. Most often, tires that are fast on the drum, remain fast, relative to other tires in the real world. John Karrasch’s testing has provided more evidence of this. The tires that are fast at BRR remain fast in the real world using Chung testing, for the most part.
Rene Herse testing has produced some robust results but has also produced results that have not replicated.
On the other hand, it was drum tests that used to indicate that 19mm tires were faster, so clearly something has changed with testing methodology. Does anyone have the cliff notes version of why drum testing is giving better results now?
Drum testing is not giving better results, there are multiple variables that have changed. Tires, especially wide tires, are made better and in a much different manner than the past. Previously, as tires became wider, they most often became thicker and stiffer as well, rarely they were designed to remain the same width.
As tires become wider, to remain with a competitive CRR, they must become thinner. This took more than a decade to become widespread implementation into the industry at large and is still not always a guaranteed design choice. Tires are also now designed in tandem with drum-driven rolling resistance machines. Tires that are designed to be fast can now be tested by the manufacturer in house to confirm the design, construction, and materials choices. Of course, designing to the drum may not always produce fast real world tires but we also see the issues when designing based on theory and prior history best practices - the Rene Herse Orondo Grande and Corkscrew climb, both of which are underperformers. On the other hand, theory and historical best practices did produce the Extralight Grand Bois, and eventually Compass/Rene Herse slicks, which are among the fastest wide tires available even now several years on from introduction.
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It’s from the first published BQ knobby test, I’m not sure which issue, maybe 75?
There are a lot of problems with Rene Herse/Bicycle Quarterly testing. Mainly that nobody else can seem to get many of their results to replicate.
Specific to what I posted, outside in the real world I think it’s almost impossible to achieve multiple runs that are within 2% of total time. In this case, 0.36 of a second. The test is something other than presented. I believe it uses moving start end points to capture the appropriate speed and then backs into the time elapsed. This methodology makes the time essentially a random variable.
That one test has 4 runs shown and averaged and the other 5 is another red flag.
The experimentation around the Rene Herse knobbies has always been poor going back several years. It’s clear that the tires are not as fast as the marketing and much effort has gone into obscuring that fact from potential buyers.
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Dude, did you not have Clif Notes when you were a kid? 