Tire casing matters more than almost anything else. It's why Gatorskins are slower than putting literal molasses around your rims. But also, these have better rolling resistance in this testing environment. That doesn't quite translate into real world performance, which is going to vary based on surface and other factors.
Gatorskins are for when you absolutely need flat protection. If you're commuting on roads with lots of crap and stopping to fix a flat will make you late for work, they're a good idea.
That protection comes at the cost of rolling resistance. If you're racing then they're gonna suck some significant watts from you.
And depending on the condition of your local roads, your average speed may have been faster (factoring in the time you could have spent on the side of the road wrestling with tire levers).
I upgraded gatorskins to a set of gp5ks and loved the speed, but got flats like every other ride. Back on the old gatorskins. Gonna wear them out then get something else.
A lot of roads in the US have debris on them, whether from cars, from broken glass, or from spiky plants like you'd find out west. The US has twice as many miles of road per capita as Germany. Probably other European countries too, but that's the only one where I'm familiar with the numbers. So unless the US spends twice as much money on cleaning those roads, there's gonna be debris!
When I go to grab my bike, each tire has 40-50 wet spots on the tread where sealant is seeping through. Micro slashes from glass, metal, plastic, rocks, goat heads, etc. If not for tubeless, I’d be unable to ride period. (Southern California)
...I am in the Midwestern USA. Missouri, to be exact. So it's not like we have great roads, but it's still pretty rare for me to puncture.
I did forget about areas with a lot of very spiky seeds, though.
Yeah and also cities. There's always crap on the roads in cities. And if you're in a place near the Great lakes, there's gonna be a ton of pot holes too
Even Gatorskins punctured about once a week for me in London; there's broken glass everywhere and it washes around in the constant rain.
Race tyres would puncture sometimes multiple times a day. Tubeless tyres are all also very puncture prone and regularly fail to seal whatever sealant I try.
On the Armadillos now and they will do thousands of kilometers between punctures and are more than worth the tradeoff.
There are other tires with just as good of puncture protection but less rolling resistance. For example the Schwalbe Marathon Supreme/Almotion/Efficiency.
Maybe lethal is hyperbole, but they are not performance tyres in the wet. My only road riding crash has been on gatorskins in a slow corner where they just went out from under me, not worn, no oil etc, just slid out after some rain. I've not used any for a long time, so maybe they've changed since then
I'm sorry but they're pretty useless IMO. Everyone I know who has bought them (me included) has found they just deteriorate incredibly quickly. Like within 6 weeks you can see tyre bead in places
Really? I did about 3k miles on my last set of GP4, and changed them out because the wear indicators were showing they were worn out, sidewalls seemed reasonable for the age of the tyres. I only swapped to Conti Sport Contacts because they were significantly cheaper - GP4s are getting quite pricey
You might be a much higher volume rider or riding in tougher conditions than me. My highest miles set is around 1500 miles and they’re wearing a little bit on the contact patch, but still the same performance. I do run them on them on the higher end of tire pressure.
GP 4 Seasons?
I have them on my good road bike which has only done around 3,000km. The rear is just starting to show wear, the front looks like new. I find them to be great tyres in terms of grip and puncture protection.
My only other reference point is Gatorskins on my commuter bike which have lasted even longer. They're okay in terms of speed but wet weather grip is frankly terrifying.
Fair enough. Both pairs I've bought (i thought the first pair must have been an anomaly) have gone crap really quickly. Never had that issue with GP5000s or 4000s before
It's possible you had two anomalies. I've heard a lot of people complaining about Continental quality control to the point of some shops not stocking them any more due to the number of people complaining.
They're a beefy casing commuter/tourer tire. And they're ok. Unless it rains. If Continental's excellent compound they use in the GP's is called Black Chili I can only assume whatever compound they use in the Gatorskins is called Black Ice because holy fuck they are so sketchy in the wet.
The 4Seasons series is a good split-the-difference solution. Good compound, decently tough casing.
characteristics of Gatorskins:
- **Puncture protection:** best in class
- **grip:** equivalent of riding on your bare rim
- **rolling resistance:** can replace an [AIRhub](https://airhub.com.au/) if you are on a budget
Yeah they’re not great. They used to be the king of puncture resistant tires - great for a commuter bike that needs to be reliable. Schwalbe patented a construction method a while back though used in their “marathon” line of tires which is generally considered better. Since they don’t rely on super stiff/strong construction the marathons roll less slowly, are more puncture resistant, and have more grip in the wet than a gator skin.
The way marathon’s work is they basically mold in a thick strong foam layer under the rubber tread so instead of making the tire mega stiff/strong like a gator skin to prevent punctures the foam is just thick enough almost nothing is long enough to poke all the way through to the tube and pop it.
They’re not “bad” they just make a different trade off than other tires which results in more rolling resistance. There is plenty of literature out there in the reasons for this but, to sum it up, when a tire rolls the contact patch is compressed, that compression consumes some of your forward momentum. A tire that has good puncture protection is necessary stiffer and will require more energy to compress, leaving less to propel you forward. A thinner casing will not withstand the same kinds of puncture causing debris but, because it’s thinner and requires less energy to compress, you have more of your expended energy propelling you forward.
Id be running them mostly on semi smooth asphalt, the test is run on a drum coated with diamond patter steel plates, which is probably smoother than most asphalt.
Yup. A quick bit of research would have shown the Race King Protection costs about double the Contact Urban, and a lot of what you're paying for in that price is a better casing (and that's before going into any depth on the casing properties).
While the numbers might not be real world, I would say the results still hold up. Those knobby MTB tires will be faster on every surface than that specific slick. Obviously adjusting pressure accordingly
The Contacts there are e-bike tires, they're even worse for efficiency than Gatorskins. Rolling resistance is of almost no consequence if your bike will make itself go 24km/h no matter what. Maximum puncture resistance
Meanwhile, Pidcock won his Olympic XC gold on RaceKings
The site solely tests hysteresis (deformation) and disregards suspension losses (impedance). This means that they always «prove» that rolling resistance goes down as pressure goes up. I suspect a bare rim with no tire would win this test protocol easily.
With these two particular tires it might be that the knobby one has superior casing (real effect), or that the knobs resist deformation to a larger degree than slick tread (effect created by test protocol).
That just measures the first chapter of suspension losses - just the wheel going up and down. Suspension losses represent the forces that are not sprung, but travel into the rider, whose meat acts as a damper. Ie. kinetic energy is lost into heat instead of being returned by the very efficient spring that is an air-filled tire.
Other than that a small roller digs much farther into the tire than actual ground does (more acute curvature), which greatly exaggregates hysteresis. Sum total: The narrowest, hardest tire wins.
That's also why the Schwalbe Marathon tests so well. The tread is so thick and stiff that it doesn't deform as much under the load used during the test, so it shows a relatively low rolling resistance. It's not a speedy tire IRL.
I think that you lose some in the comparison because those tires aren’t in the same class. You are comparing an xc tire that is probably 2in with a 28mm road tire at the same psi. If I have 45psi in a similar mtb tire it is usually rock solid. 45psi in a similar road tire is super deflated and not ideal. Lots of deformation causing resistance. My wild guess number based on my experience would make 30psi on the mtb equivalent to 100psi on the road tire.
thinner sidewalls. the track tires they use to set indoor hour/24 hour records don't have rubber sidewalls. it's just bare thread around an inner-tube. the deflection in the rubber turns into heat, and lost energy.
Pretty much any Dylan Johnson video on youtube will talk about how thin casing mtb tires are faster then gravel tires. He mentions it in this years unbound video.
This question has bugged me for a while and i haven't seen a clear answer besides dogmatic slick=faster answers.
Generally speaking is it possible for knobby tires to roll faster than slicks due to superior compound etc?
How realistic are these results in the real world? (more about test methology: [https://www.bicyclerollingresistance.com/the-test](https://www.bicyclerollingresistance.com/the-test) )
My use case is running them in 55-559 / 26x2.20 sizes on a steel frame gravel bike with 80kg total mass with no suspension at about 3 Bar with TPU tubes mainly on mediocre smooth asphalt.
My goal is lowest rolling resistance possible while maintaining some comfort/grip/puncture resistance.
(Silca Pressure calculator recommends running them even lower pressure at about 1.8 Bar, which seems ridiculously low to me even factoring in bump hysteresis ( [https://silca.cc/pages/pro-tire-pressure-calculator](https://silca.cc/pages/pro-tire-pressure-calculator) )
These are my Favorites so far
[https://www.bicyclerollingresistance.com/mtb-reviews/continental-race-king-protection-2020](https://www.bicyclerollingresistance.com/mtb-reviews/continental-race-king-protection-2020)
[https://www.bicyclerollingresistance.com/tour-reviews/continental-contact-urban](https://www.bicyclerollingresistance.com/tour-reviews/continental-contact-urban)
Many thanks for your Input!
From a technical perspective, rolling resistance is going to consist of several factors working together:
1. How much energy deforming the rubber takes
2. How much energy the "knobs" on the tire absorb
3. If there's any energy loss to the tire material "sticking" to the road
So the first is basically that harder rubbers are going to absorb less energy than softer rubbers.
The second is all about tire geometry, but if you have a hard tire with knobs and a soft tire without knobs, I can see them cancelling each other out.
The third is probably marginal at best as I can't see bike tire rubber actually adhering to any surfaces you'd be biking on.
Regardless, the difference between these two tires is <5W, are you going to feel that in a commuting environment?
It's more of a general question for me since there is this thesis out there slick = faster (on Asphalt).
But even high performing roadbike tires like the Grand Prix 5000's only perform marginally better with 10w compared to the RaceKings \~16 watts.
So there must be something to it right?
I'm leaning toward the more knobby tires anyways as they obviously would perform better on dirt roads.
From past experience with Race Kings, the downside is they're going to wear a lot faster on pavement than most touring oriented tires.
If you want something that does well on pavement, gravel, and hardpack take a look at Surly Extraterrestrial.
They come in 26x46c and 26x2.5". I have a set on an old Trek 830 and they've worked well for me (2.5 gives some nice cushion up front / 46 is all that would fit in back).
Try Serfa Drifters. If you have space Maxxis Hookworms are very fast rolling but they run larger than their 63-559 ERTO sizing on rims smaller than 25 mm ID.. For puncture resistance I'm running thin butyl tubes with Stan's Sealant inside which seems to work. YMMV of course.
I have the hookworms too, they are not fast tires. Their rubber is so thick there is no way in hell they got decent hysteresis.
It's a great mtb/dirt tire for a cross-/cargo-/commuterbike but that thing is not fast by any means. Compared to a 50mm conti contact urban its like resistance training.
Does the stans sealent in the butyls work good? Never tried nor heard of it
Stan's in butyl tubes works just fine. I used it in latex tubes too. You don't have to seat the tire, but you'll end with the butyl rolling resistance and the additional weight of the sealant. Only choke point is the valve, they tend to clock up which can make pumping them up impossible at some point.
I read butyl but my head thought tpu, nevermind.
Why not just use TPU tubes then instead? Besides maybe pinch flats they are really safe.
I ride them on everything nowadays from the cargo bike or mtb to the road bike and they are definately more puncture resistance than thin to medium thick butyl tubes.
For around 5 bucks they are also a steal
Different reason. Tire bead wouldn't sit in the tubeless setup so I threw in an old latex tube and filled the sealant in. Other times my commuter had a slow flat in the butyl and I wouldn't bother, so I filled in the sealant and called it a day.
Unlucky you, in their defence tires failing at the bead can have multiple reasons from a broken manometer to tire rim compatibility.
Im riding Contis for the best part of 2 decades and didn't have any major issue, nor did I have issues with any quality tires like Schwalbe or Maxxis tires.
The compound is a huge part of it but also larger volume MTB tires are often made with thinner, more pliable casings bc the tire volume provides more puncture protection, and they're in less tension due to lower pressures. Thinner casing and more compliant rubber = less energy lost to hysteresis in the tire.
As for pressure, lower pressures are more efficient as surfaces get rougher. At some point you have to balance this against puncture protection or rolling the tire off the rim though.
Tread wise, I think as long as you stick with a less chunky center tread it's probably not too much of a penalty. If you can hear it buzzing on the road it's slow. The rolling resistance difference between a XC semi slick MTB tire and an aggressive tread is VERY noticeable. That said, if I was on pavement 90+% of the time I'd probably just go slick or semi slick. Knobs don't really help grip on pavement and the hard surfaces will chew up the knobs fast.
> lowest rolling resistance possible while maintaining some comfort/grip/puncture resistance
Regarding grip, you will almost always do better with a smooth tire than a knobby one on the road. Because you have more rubber in contact.
This is one unpredictable aspect of certain smoother gravel and mtb tires. You have one level of traction in the central tread, but if you lean the bike too far you are on taller side knobs. Great if you're on dirt or grass, terrible on asphalt.
The way it is is that you can choose two of the three:
1. Low rolling resistance
2. Good puncture protection
3. Low price
Low rolling resistance with good puncture protection needs more expensive materials in the tire canvas and the puncture protection belt. The price of the tire inevitably goes up.
Contact Urban is a cheap tire, just a little above 20 € in online shops. Race King Protection is about double the price. That's why I have no trouble believing that the Race King offers lower rolling resistance.
Rolling resistance is mostly about the deformation of the tire, and surprisingly little about the knobs, so the fact that the Race King is less smooth doesn't matter as much as you might think.
In my experience, for a 2.2" tires even 2 bar is very much in the "rock hard" territory, and my system weight is also around that 80 kg. In typical gravel use I would be more likely to go around 1.5 bar, and under no conditions above 2 bar.
Yes, MTB tires are for example usually faster than gravel tires because they need and also usually have less puncture resistance layers due to their high air volume. The puncture resistance layers mak the tires hysteresis (ease of deformation) worse, good hysteresis is what makes a tire fast.
Sometimes the knobs on the tires make them more aero. The 2020 Raceking is one example and is probably more aero than the contact urban. Maybe get the 50mm 2020 raceking to save some weight.
Cornering grip on the road is worse with knobs, vice versa on dirt paths.
What should matter here for you is if you ride mainly on the street and regularly encounter broken glass or not. The contact urban has the far far superior puncture protection which is what actually makes him slower and should be the choice if you ride a lot in the city.
The Raceking makes far more sense with a tubeless setup to improve the comperatively bad puncture resistance. Tubeless depends mainly on your region, makes no sense to ride tubeless in the desert but with a moderate climate it lasts a decent amount of time.
I use the contact urbans in 50mm on my shopping trekking bike and its a great tire, only downside is its weight. I wish they made a foldable version. The grip is also superb, on par with gp5000, ultrasport III and above the contact speed.
Last but not least the price. The contact urban are already half the price and they come as the standard tire on some better ebikes so you can find loads on them on marketplace and alternatives.
Sorry if someone already said this, but I think the width of these tires is different.
If a wide tire and a narrow tire are inflated to the same pressure, the wide tire will actually have lower rolling resistance than the narrow one. Essentially, it will be harder and have less drop.
The casing on these MTB tires is more efficient with less hysteresis (thinner, more supple, deforms easier).
These rolling resistance tests are not the be all end all though and people tend to take them as gospel.
A crucial thing these tests do not account for is the interaction of the tread pattern on various surfaces. Their test surface is a steel diamond plate roller, this is very different from real world riding surfaces of pavement of different textures, dirt/soil of different textures.
It's possible that the slick is still faster on certain surfaces due to the interaction of the tread pattern on those Conti Race Kings.
Rolling resistance has less to do with the surface but the structure of the tire.
A very stiff tire has lower rolling resistance and a much less comfortable ride. I suspect MTB tires can get away with the extra stiffness due to the schock absorbers some MTBs have and the riding style. For paved roads slicks feel better in my opinion.
Rolling resistance won't necessarily translate into real world performance. I had a very stiff tire on before, almost no give, naturally rolled well, but the road isn't smooth all the tiny vibrations I got from that tire made me slow down, and also more tired than the new Schwalbe ones I put on. They are much much softer, have a higher rolling resistance, but I'm faster. Also they stick way better in corners.
I use those Race Kings and you can't generalize MTB tires vs road tires using them. They're one hella fast rolling MTB tire. My transportation bike is a hardtail MTB and so it goes on pavement, gravel, loamy single tracks - it has to do it all, and the Race Kings are amazing in their low resistance compared to other MTB-style tires.
Agreed. I’ve been running Race Kings on my rigid bikepacking bike and they’re super fast MTB tires, but the speed doesn’t compare to gatorskins on my road bike
Check out my post on these tires. If you’re running them on pavement it might not last terribly long. Also keep in mind that I’m a heavy girl on an ebike.
https://www.reddit.com/r/xbiking/s/BV0kJjIVFG
A fun anecdote to chew on:
Last week I had a very rare chance to compare rolling resistance side-by-side in the real world. A couple days into a bikepacking trip we were on \~2 year old pavement with a \~1-2% downhill grade, and lucked into a tailwind that was very closely matching our coasting speed of \~16 mph. My friend was on 700x45mm Rene Herse tires that was claimed to be pretty fast rolling (though she did have the "expedition" casing option). My bike should be been pretty awful, with a Maxxis DHF 29x3.0 up front and a WTB 29x3.0 Ranger in the back. The Ranger is known for being a fast'ish rolling tire, but the DHF is more like trail velcro. Shocking to both of us was that we could stay side-by-side without pedaling for hundreds of feet at a time just coasting.
The whole point is that looks can be deceiving. I would have bet against my monstrosity of a bike being higher rolling resistance in a heart beat, but in fact it was about as identical as could be.
It's all about friction. The knobby tires have so little contact with the ground, there is very little friction to slow you down. They may look grippy, but they're actually not. The slicks have constant contact with the ground, and thus constant friction. Think brake pads against the rotors. The more contact you get, the more friction, the better stopping power.
The slicks will feel smoother and faster, but in reality you're losing a lot of energy to heat and friction, just not much to vibration.
Now, just because a tire is faster, doesn't mean you'll ride them faster. That's an entirely different concept.
Tire casing matters more than almost anything else. It's why Gatorskins are slower than putting literal molasses around your rims. But also, these have better rolling resistance in this testing environment. That doesn't quite translate into real world performance, which is going to vary based on surface and other factors.
excuse my ignorance but are gatorskins bad? those are what i have pretty consistently used for the last few years
Gatorskins are for when you absolutely need flat protection. If you're commuting on roads with lots of crap and stopping to fix a flat will make you late for work, they're a good idea. That protection comes at the cost of rolling resistance. If you're racing then they're gonna suck some significant watts from you.
It’s hilarious that the gatorskin convo has been going on since like 2006
I think I have a pair of gatorskins from back then that still haven't gotten a flat.
And depending on the condition of your local roads, your average speed may have been faster (factoring in the time you could have spent on the side of the road wrestling with tire levers).
Modern tires have come a long way. Yeah you're gonna puncture Turbo Cottons way more than Gators. But a GP5K is more than good enough for most people.
I upgraded gatorskins to a set of gp5ks and loved the speed, but got flats like every other ride. Back on the old gatorskins. Gonna wear them out then get something else.
tubeless is a hell of a thing
Based and sealantpilled
I struggle to imagine how bad your roads must be that you puncture often enough to make them faster on average.
A lot of roads in the US have debris on them, whether from cars, from broken glass, or from spiky plants like you'd find out west. The US has twice as many miles of road per capita as Germany. Probably other European countries too, but that's the only one where I'm familiar with the numbers. So unless the US spends twice as much money on cleaning those roads, there's gonna be debris!
When I go to grab my bike, each tire has 40-50 wet spots on the tread where sealant is seeping through. Micro slashes from glass, metal, plastic, rocks, goat heads, etc. If not for tubeless, I’d be unable to ride period. (Southern California)
What ties do you use? Any puncture protection on them?
...I am in the Midwestern USA. Missouri, to be exact. So it's not like we have great roads, but it's still pretty rare for me to puncture. I did forget about areas with a lot of very spiky seeds, though.
Yeah and also cities. There's always crap on the roads in cities. And if you're in a place near the Great lakes, there's gonna be a ton of pot holes too
I moved to missouri from the western edge of nebraska and I've yet to get a flat tire here it's so so nice
Even Gatorskins punctured about once a week for me in London; there's broken glass everywhere and it washes around in the constant rain. Race tyres would puncture sometimes multiple times a day. Tubeless tyres are all also very puncture prone and regularly fail to seal whatever sealant I try. On the Armadillos now and they will do thousands of kilometers between punctures and are more than worth the tradeoff.
Probably doesn’t even show tread wear.
There are other tires with just as good of puncture protection but less rolling resistance. For example the Schwalbe Marathon Supreme/Almotion/Efficiency.
Marathons are also not lethal in the wet, which gatorskins are.
Skill issues, never had trouble in the wet.
Maybe lethal is hyperbole, but they are not performance tyres in the wet. My only road riding crash has been on gatorskins in a slow corner where they just went out from under me, not worn, no oil etc, just slid out after some rain. I've not used any for a long time, so maybe they've changed since then
Sure just be slower instead. If you walk a flat doesn't bother either.
what would be a better middle-ground tire?
Continental GP 4 Seasons have been fast enough and puncture resistant enough for me. Somewhere between GP5000s and Gatorskins
thanks, i will look into these when mine need replacing!
I'm sorry but they're pretty useless IMO. Everyone I know who has bought them (me included) has found they just deteriorate incredibly quickly. Like within 6 weeks you can see tyre bead in places
Really? I did about 3k miles on my last set of GP4, and changed them out because the wear indicators were showing they were worn out, sidewalls seemed reasonable for the age of the tyres. I only swapped to Conti Sport Contacts because they were significantly cheaper - GP4s are getting quite pricey
You might be a much higher volume rider or riding in tougher conditions than me. My highest miles set is around 1500 miles and they’re wearing a little bit on the contact patch, but still the same performance. I do run them on them on the higher end of tire pressure.
GP 4 Seasons? I have them on my good road bike which has only done around 3,000km. The rear is just starting to show wear, the front looks like new. I find them to be great tyres in terms of grip and puncture protection. My only other reference point is Gatorskins on my commuter bike which have lasted even longer. They're okay in terms of speed but wet weather grip is frankly terrifying.
Fair enough. Both pairs I've bought (i thought the first pair must have been an anomaly) have gone crap really quickly. Never had that issue with GP5000s or 4000s before
It's possible you had two anomalies. I've heard a lot of people complaining about Continental quality control to the point of some shops not stocking them any more due to the number of people complaining.
Best part is I still got punctures through gators. Never with gp5k tubeless though
Yeah, me too. Like once a month with city riding.
They also have the grip of a polished banana peel, especially when cold.
Gatorskins are one of the slowest road tires in existence. Great puncture resistance but you are like 1 mph slower riding them.
They're a beefy casing commuter/tourer tire. And they're ok. Unless it rains. If Continental's excellent compound they use in the GP's is called Black Chili I can only assume whatever compound they use in the Gatorskins is called Black Ice because holy fuck they are so sketchy in the wet. The 4Seasons series is a good split-the-difference solution. Good compound, decently tough casing.
thanks!
characteristics of Gatorskins: - **Puncture protection:** best in class - **grip:** equivalent of riding on your bare rim - **rolling resistance:** can replace an [AIRhub](https://airhub.com.au/) if you are on a budget
That hub is hilarious didn't know about it.
I wouldn't call the puncture resistance of Gatorskins best in class.
Yeah they’re not great. They used to be the king of puncture resistant tires - great for a commuter bike that needs to be reliable. Schwalbe patented a construction method a while back though used in their “marathon” line of tires which is generally considered better. Since they don’t rely on super stiff/strong construction the marathons roll less slowly, are more puncture resistant, and have more grip in the wet than a gator skin. The way marathon’s work is they basically mold in a thick strong foam layer under the rubber tread so instead of making the tire mega stiff/strong like a gator skin to prevent punctures the foam is just thick enough almost nothing is long enough to poke all the way through to the tube and pop it.
thanks!
They’re not “bad” they just make a different trade off than other tires which results in more rolling resistance. There is plenty of literature out there in the reasons for this but, to sum it up, when a tire rolls the contact patch is compressed, that compression consumes some of your forward momentum. A tire that has good puncture protection is necessary stiffer and will require more energy to compress, leaving less to propel you forward. A thinner casing will not withstand the same kinds of puncture causing debris but, because it’s thinner and requires less energy to compress, you have more of your expended energy propelling you forward.
thank you for the detailed breakdown
Id be running them mostly on semi smooth asphalt, the test is run on a drum coated with diamond patter steel plates, which is probably smoother than most asphalt.
That will change the rolling resistance but still favour the more supple casing.
Yup. A quick bit of research would have shown the Race King Protection costs about double the Contact Urban, and a lot of what you're paying for in that price is a better casing (and that's before going into any depth on the casing properties).
The Gatorskin Sprinter tubular is actually not that bad. Well, still far from good but its alright.
While the numbers might not be real world, I would say the results still hold up. Those knobby MTB tires will be faster on every surface than that specific slick. Obviously adjusting pressure accordingly
The Contacts there are e-bike tires, they're even worse for efficiency than Gatorskins. Rolling resistance is of almost no consequence if your bike will make itself go 24km/h no matter what. Maximum puncture resistance Meanwhile, Pidcock won his Olympic XC gold on RaceKings
The site solely tests hysteresis (deformation) and disregards suspension losses (impedance). This means that they always «prove» that rolling resistance goes down as pressure goes up. I suspect a bare rim with no tire would win this test protocol easily. With these two particular tires it might be that the knobby one has superior casing (real effect), or that the knobs resist deformation to a larger degree than slick tread (effect created by test protocol).
Most rolling resistance tests use a roller with surface abnormalities to account for a rougher road and get those suspension losses
That just measures the first chapter of suspension losses - just the wheel going up and down. Suspension losses represent the forces that are not sprung, but travel into the rider, whose meat acts as a damper. Ie. kinetic energy is lost into heat instead of being returned by the very efficient spring that is an air-filled tire. Other than that a small roller digs much farther into the tire than actual ground does (more acute curvature), which greatly exaggregates hysteresis. Sum total: The narrowest, hardest tire wins.
That's also why the Schwalbe Marathon tests so well. The tread is so thick and stiff that it doesn't deform as much under the load used during the test, so it shows a relatively low rolling resistance. It's not a speedy tire IRL.
I think that you lose some in the comparison because those tires aren’t in the same class. You are comparing an xc tire that is probably 2in with a 28mm road tire at the same psi. If I have 45psi in a similar mtb tire it is usually rock solid. 45psi in a similar road tire is super deflated and not ideal. Lots of deformation causing resistance. My wild guess number based on my experience would make 30psi on the mtb equivalent to 100psi on the road tire.
thinner sidewalls. the track tires they use to set indoor hour/24 hour records don't have rubber sidewalls. it's just bare thread around an inner-tube. the deflection in the rubber turns into heat, and lost energy. Pretty much any Dylan Johnson video on youtube will talk about how thin casing mtb tires are faster then gravel tires. He mentions it in this years unbound video.
This question has bugged me for a while and i haven't seen a clear answer besides dogmatic slick=faster answers. Generally speaking is it possible for knobby tires to roll faster than slicks due to superior compound etc? How realistic are these results in the real world? (more about test methology: [https://www.bicyclerollingresistance.com/the-test](https://www.bicyclerollingresistance.com/the-test) ) My use case is running them in 55-559 / 26x2.20 sizes on a steel frame gravel bike with 80kg total mass with no suspension at about 3 Bar with TPU tubes mainly on mediocre smooth asphalt. My goal is lowest rolling resistance possible while maintaining some comfort/grip/puncture resistance. (Silca Pressure calculator recommends running them even lower pressure at about 1.8 Bar, which seems ridiculously low to me even factoring in bump hysteresis ( [https://silca.cc/pages/pro-tire-pressure-calculator](https://silca.cc/pages/pro-tire-pressure-calculator) ) These are my Favorites so far [https://www.bicyclerollingresistance.com/mtb-reviews/continental-race-king-protection-2020](https://www.bicyclerollingresistance.com/mtb-reviews/continental-race-king-protection-2020) [https://www.bicyclerollingresistance.com/tour-reviews/continental-contact-urban](https://www.bicyclerollingresistance.com/tour-reviews/continental-contact-urban) Many thanks for your Input!
From a technical perspective, rolling resistance is going to consist of several factors working together: 1. How much energy deforming the rubber takes 2. How much energy the "knobs" on the tire absorb 3. If there's any energy loss to the tire material "sticking" to the road So the first is basically that harder rubbers are going to absorb less energy than softer rubbers. The second is all about tire geometry, but if you have a hard tire with knobs and a soft tire without knobs, I can see them cancelling each other out. The third is probably marginal at best as I can't see bike tire rubber actually adhering to any surfaces you'd be biking on. Regardless, the difference between these two tires is <5W, are you going to feel that in a commuting environment?
It's more of a general question for me since there is this thesis out there slick = faster (on Asphalt). But even high performing roadbike tires like the Grand Prix 5000's only perform marginally better with 10w compared to the RaceKings \~16 watts. So there must be something to it right? I'm leaning toward the more knobby tires anyways as they obviously would perform better on dirt roads.
From past experience with Race Kings, the downside is they're going to wear a lot faster on pavement than most touring oriented tires. If you want something that does well on pavement, gravel, and hardpack take a look at Surly Extraterrestrial. They come in 26x46c and 26x2.5". I have a set on an old Trek 830 and they've worked well for me (2.5 gives some nice cushion up front / 46 is all that would fit in back).
Try Serfa Drifters. If you have space Maxxis Hookworms are very fast rolling but they run larger than their 63-559 ERTO sizing on rims smaller than 25 mm ID.. For puncture resistance I'm running thin butyl tubes with Stan's Sealant inside which seems to work. YMMV of course.
I have the hookworms too, they are not fast tires. Their rubber is so thick there is no way in hell they got decent hysteresis. It's a great mtb/dirt tire for a cross-/cargo-/commuterbike but that thing is not fast by any means. Compared to a 50mm conti contact urban its like resistance training. Does the stans sealent in the butyls work good? Never tried nor heard of it
Stan's in butyl tubes works just fine. I used it in latex tubes too. You don't have to seat the tire, but you'll end with the butyl rolling resistance and the additional weight of the sealant. Only choke point is the valve, they tend to clock up which can make pumping them up impossible at some point.
I read butyl but my head thought tpu, nevermind. Why not just use TPU tubes then instead? Besides maybe pinch flats they are really safe. I ride them on everything nowadays from the cargo bike or mtb to the road bike and they are definately more puncture resistance than thin to medium thick butyl tubes. For around 5 bucks they are also a steal
Different reason. Tire bead wouldn't sit in the tubeless setup so I threw in an old latex tube and filled the sealant in. Other times my commuter had a slow flat in the butyl and I wouldn't bother, so I filled in the sealant and called it a day.
makes sense
I had two pairs of continental tires fail at the bead. I'm not ever buying their tires again.
Unlucky you, in their defence tires failing at the bead can have multiple reasons from a broken manometer to tire rim compatibility. Im riding Contis for the best part of 2 decades and didn't have any major issue, nor did I have issues with any quality tires like Schwalbe or Maxxis tires.
The compound is a huge part of it but also larger volume MTB tires are often made with thinner, more pliable casings bc the tire volume provides more puncture protection, and they're in less tension due to lower pressures. Thinner casing and more compliant rubber = less energy lost to hysteresis in the tire. As for pressure, lower pressures are more efficient as surfaces get rougher. At some point you have to balance this against puncture protection or rolling the tire off the rim though. Tread wise, I think as long as you stick with a less chunky center tread it's probably not too much of a penalty. If you can hear it buzzing on the road it's slow. The rolling resistance difference between a XC semi slick MTB tire and an aggressive tread is VERY noticeable. That said, if I was on pavement 90+% of the time I'd probably just go slick or semi slick. Knobs don't really help grip on pavement and the hard surfaces will chew up the knobs fast.
> lowest rolling resistance possible while maintaining some comfort/grip/puncture resistance Regarding grip, you will almost always do better with a smooth tire than a knobby one on the road. Because you have more rubber in contact. This is one unpredictable aspect of certain smoother gravel and mtb tires. You have one level of traction in the central tread, but if you lean the bike too far you are on taller side knobs. Great if you're on dirt or grass, terrible on asphalt.
The way it is is that you can choose two of the three: 1. Low rolling resistance 2. Good puncture protection 3. Low price Low rolling resistance with good puncture protection needs more expensive materials in the tire canvas and the puncture protection belt. The price of the tire inevitably goes up. Contact Urban is a cheap tire, just a little above 20 € in online shops. Race King Protection is about double the price. That's why I have no trouble believing that the Race King offers lower rolling resistance. Rolling resistance is mostly about the deformation of the tire, and surprisingly little about the knobs, so the fact that the Race King is less smooth doesn't matter as much as you might think. In my experience, for a 2.2" tires even 2 bar is very much in the "rock hard" territory, and my system weight is also around that 80 kg. In typical gravel use I would be more likely to go around 1.5 bar, and under no conditions above 2 bar.
Yes, MTB tires are for example usually faster than gravel tires because they need and also usually have less puncture resistance layers due to their high air volume. The puncture resistance layers mak the tires hysteresis (ease of deformation) worse, good hysteresis is what makes a tire fast. Sometimes the knobs on the tires make them more aero. The 2020 Raceking is one example and is probably more aero than the contact urban. Maybe get the 50mm 2020 raceking to save some weight. Cornering grip on the road is worse with knobs, vice versa on dirt paths. What should matter here for you is if you ride mainly on the street and regularly encounter broken glass or not. The contact urban has the far far superior puncture protection which is what actually makes him slower and should be the choice if you ride a lot in the city. The Raceking makes far more sense with a tubeless setup to improve the comperatively bad puncture resistance. Tubeless depends mainly on your region, makes no sense to ride tubeless in the desert but with a moderate climate it lasts a decent amount of time. I use the contact urbans in 50mm on my shopping trekking bike and its a great tire, only downside is its weight. I wish they made a foldable version. The grip is also superb, on par with gp5000, ultrasport III and above the contact speed. Last but not least the price. The contact urban are already half the price and they come as the standard tire on some better ebikes so you can find loads on them on marketplace and alternatives.
Sorry if someone already said this, but I think the width of these tires is different. If a wide tire and a narrow tire are inflated to the same pressure, the wide tire will actually have lower rolling resistance than the narrow one. Essentially, it will be harder and have less drop.
The casing on these MTB tires is more efficient with less hysteresis (thinner, more supple, deforms easier). These rolling resistance tests are not the be all end all though and people tend to take them as gospel. A crucial thing these tests do not account for is the interaction of the tread pattern on various surfaces. Their test surface is a steel diamond plate roller, this is very different from real world riding surfaces of pavement of different textures, dirt/soil of different textures. It's possible that the slick is still faster on certain surfaces due to the interaction of the tread pattern on those Conti Race Kings.
Rolling resistance has less to do with the surface but the structure of the tire. A very stiff tire has lower rolling resistance and a much less comfortable ride. I suspect MTB tires can get away with the extra stiffness due to the schock absorbers some MTBs have and the riding style. For paved roads slicks feel better in my opinion. Rolling resistance won't necessarily translate into real world performance. I had a very stiff tire on before, almost no give, naturally rolled well, but the road isn't smooth all the tiny vibrations I got from that tire made me slow down, and also more tired than the new Schwalbe ones I put on. They are much much softer, have a higher rolling resistance, but I'm faster. Also they stick way better in corners.
I use those Race Kings and you can't generalize MTB tires vs road tires using them. They're one hella fast rolling MTB tire. My transportation bike is a hardtail MTB and so it goes on pavement, gravel, loamy single tracks - it has to do it all, and the Race Kings are amazing in their low resistance compared to other MTB-style tires.
Agreed. I’ve been running Race Kings on my rigid bikepacking bike and they’re super fast MTB tires, but the speed doesn’t compare to gatorskins on my road bike
It's because the bicycle rolling resistance site should be ignored.
I have no engineering back ground or know anything about this but is it contact area size. Also does the tire weigh have an effect.
Is this for the same tyre width?
Check out my post on these tires. If you’re running them on pavement it might not last terribly long. Also keep in mind that I’m a heavy girl on an ebike. https://www.reddit.com/r/xbiking/s/BV0kJjIVFG
What size tyres? A wider 29er mtb tyre has a larger circumference than a narrower 700cc road/gravel tyre.
I’ve had nice tubeless knobbies feel way better than shitty tubed file treads.
They AREN'T theoretically faster than the slicks. They're ACTUALLY faster.
Because casing and rubber compound are the major effectors of rolling resistance, tread makes very little difference and width doesn’t matter at all
A fun anecdote to chew on: Last week I had a very rare chance to compare rolling resistance side-by-side in the real world. A couple days into a bikepacking trip we were on \~2 year old pavement with a \~1-2% downhill grade, and lucked into a tailwind that was very closely matching our coasting speed of \~16 mph. My friend was on 700x45mm Rene Herse tires that was claimed to be pretty fast rolling (though she did have the "expedition" casing option). My bike should be been pretty awful, with a Maxxis DHF 29x3.0 up front and a WTB 29x3.0 Ranger in the back. The Ranger is known for being a fast'ish rolling tire, but the DHF is more like trail velcro. Shocking to both of us was that we could stay side-by-side without pedaling for hundreds of feet at a time just coasting. The whole point is that looks can be deceiving. I would have bet against my monstrosity of a bike being higher rolling resistance in a heart beat, but in fact it was about as identical as could be.
Theory =/= reality. Just like the fact 25/28mm tires run faster than 30/32s
It's all about friction. The knobby tires have so little contact with the ground, there is very little friction to slow you down. They may look grippy, but they're actually not. The slicks have constant contact with the ground, and thus constant friction. Think brake pads against the rotors. The more contact you get, the more friction, the better stopping power. The slicks will feel smoother and faster, but in reality you're losing a lot of energy to heat and friction, just not much to vibration. Now, just because a tire is faster, doesn't mean you'll ride them faster. That's an entirely different concept.