Like many cyclists, we love climbs, but we live for twisty downhills. The feeling of the bike leaning deep into a turn is something that is hard to explain, yet easy to enjoy.

This video clip was taken on a short descent toward Lake Washington. We know this road well, and even though we aren’t taking any risks, it’s always fun.

Obviously, one key component in making descents fun and safe are good tires. What makes a tire corner well? Here are some factors that determine cornering grip on pavement.

Most important is a round profile. That way, the tire’s behavior is always the same, no matter how far you lean the bike.

Some older tires were taller in the center – I believe the idea was that you’d roll on a narrower portion of the tire, which was thought to be faster. This caused strange transitions as the effective radius of the tire changed as you leaned the bike. Some tires have a squared-off profile. That is even worse, as amount of rubber on the road decreases dramatically as you lean the bike into the corner. Fortunately, most ‘road’ tires today are round.

Next in the order of importance is the rubber compound. A grippy rubber compound will make the tire stick better to the road surface.

In the past, we had to choose between grippy rubber that wore out quickly, or durable tires that provided heart-stopping moments when they suddenly lost traction and skipped sideways.

Today, the best rubber compounds combine excellent grip with long life, giving us the best of both worlds.

The width of the tire is also very important. More rubber on the road provides more grip – that is why racing motorbikes use wide tires.

On bicycles, there are two reasons why wider tires grip better. They run at lower pressures. This allows them to stay in contact with the road surface better. When a narrow tire skips over a bump, it loses traction. The suppleness of the casing plays a role, too: A tire that absorbs bumps better also has more traction.

Reason 2 why wide tires have more grip: The tread rubber interlocks with the irregularities of the road surface. A wider tires can interlock with more surface irregularities, so it has more grip. (No. 2 appears to be the main reason why racing motorbikes have wide tires.)

Tread patterns also contribute to the grip of a tire, or reduce it. Micro-knobs that squirm under cornering loads should be avoided. The most grippy treads are designed to provide as many interlocking edges as possible. This is especially important on wet roads, where the pure friction between rubber and asphalt is much reduced. But you’ll notice the effect even in dry corners.

Why do racing motorbikes use slick tires? Motorbikes are too heavy and too powerful to use fine ribs – they’d wear off immediately. Instead, they use very soft rubber compounds. The heavy weight and high speed of the motorbike pushes the tire into the road, thus creating the interlock with the road surface. The downside is that racing motorbike tires wear out very quickly.

Tire pressure is important, too. It’s a compromise: Pump up your tires too hard, and they’ll skip over bumps and lose traction. Run the pressure too low, and the tire can collapse during hard cornering. If your pressure is just a bit too low, you’ll just notice that the bike is running wide. If it’s much too low, the sidewall can suddenly collapse, which isn’t a good feeling at all. Fortunately, there is a wide range of ‘OK’ pressures between these extremes.

Temperature is important, too. Rubber becomes more sticky when it’s warm. On a cold day, the grip from your tires will be much reduced – even if you don’t run into ice.

Racing motorbikes warm up their tires for optimum grip, but cyclists are too light to generate significant heat when cornering.

At least as important as the outright grip of your tires is the feedback they provide as you corner. Narrow tires provide very little, but wide tires with good tread patterns give you feedback of how much grip you have in reserve. It’s subtle, but once you know what it feels like, you can sense whether you have a lot of grip in reserve, or whether you are approaching the limit. The best way to learn what this feels like is to ride on slippery surfaces – mud or snow – where you can slide at low speeds and (usually) recover from the slide. But that is a topic for another post…

In summary, to corner with confidence, you want a tire that is round, wide, supple, with a tread pattern that interlocks with the road surface, a rubber compound that grips well – and ideally, you’ll ride on a warm or hot day.

At Rene Herse Cycles, we love descending, so we’ve optimized our tires for all these factors – except the weather. You’ll have to provide that yourself.

Click here for more information about Rene Herse tires.

Working with Ted King, winner of last year’s Dirty Kanza gravel race, has added a new perspective to our R&D. We’ve got a lot of experience riding gravel, even racing it, but today’s mass-start races aren’t the same as exploring the Cascade Mountains on forest roads, or even racing the 363-mile cross-state Oregon Outback during the early days of gravel racing.

Like all racers, Ted wants the fastest bike he can get, and supple tires make a greater difference than almost any other component choice. Depending on the surface, Ted has been racing our 42 mm Snoqualmie Pass (Landrun 100, 2nd place), 35 mm Bon Jon Pass (Belgian Waffle Ride, 3rd place) and 38 mm Steilacoom knobbies (Epic 150, 1st place).

For Dirty Kanza and similar big events, Ted asked for a tougher tire. When you race in a peloton, you don’t see where you are going. It’s inevitable that you’ll hit some rocks and holes that you’d go around if you were riding by yourself or in a small group. And unlike the smooth gravel often found in New England (above), some of the rocks in Kansas are awfully rough and sharp.

How do you make a sturdier tire without giving up the speed and wonderful ride of our Rene Herse tires? For our new Endurance tires, we started with our Extralight casing, but pushed the threads closer together to make a denser weave for improved cut resistance. Then we added a thin protection layer all around the tire that further enhances cut-resistance and puncture protection. The darker tan color distinguishes this casing from our other offerings.

By using the same ultra-fine threads as our Extralight casing, the new Endurance tires give up only a little speed. In return, you get significantly improved resistance to rock cuts and flats. And since we start with the Extralight casing, the Endurance tires don’t weigh a ton either – no more than our already very light Standard casings. As part of our testing, Ted King has been riding prototypes with the new Endurance casing. In fact, he used them to win the Epic 150 gravel race a few weeks ago.

The Endurance casing is also a great choice for adventures where you don’t know what to expect. It’s a perfect complement to our dual-purpose knobbies that offer great performance on pavement, gravel, mud and even snow. Combine the two, and there is little your bike won’t be able to handle.

For the punishing conditions of the world’s toughest gravel races, we’ve developed the Endurance Plus casing. This uses much stronger, thicker threads, plus the same protection layer as the Endurance casing. This is a tire you might choose when the race will be a game of attrition… (Did I hear someone say Dirty Kanza?)

Gravel racers also tell us that they need wider tires, but most modern cyclocross and many gravel bikes only fit 44 mm tires (if they are smooth) or 42 mm knobbies. We already have our 700C x 44 mm Snoqualmie Pass, and now they are joined by the 700C x 42 mm Hurricane Ridge dual-purpose knobbies.

Hurricane Ridge is a great climb in the Olympic Mountains of Washington that offers two options: paved or muddy gravel. With the new dual-purpose knobbies, you’ll feel equally at home on both routes.

All this adds up to a lot of new tire models in the Rene Herse Cycles program:

• 700C x 38 mm Steilacoom Endurance
• 700C x 42 mm Hurricane Ridge Standard
• 700C x 42 mm Hurricane Ridge Extralight
• 700C x 42 mm Hurricane Ridge Endurance
• 700C x 42 mm Hurricane Ridge Endurance Plus
• 650B x 48 mm Juniper Ridge Endurance

With Dirty Kanza approaching, we’ve airshipped the first of the new tires from Japan to give riders and racers additional options as they prepare this epic (and other) events. Quantities are very limited for now. If you need your tires for Dirty Kanza, select an expedited shipping method and add “Tires for Kanza” in the note field, and we’ll send out your order as quickly as possible – usually the same day. (In fact, most orders are shipped the same day.)

All our other models are in stock, too. Together with the new tires, they provide a full quiver to suit most riders and most events. Click here for more information or to order.

Photo credits: Ansel Dickey (Photos 1, 3, 10), Landrun 100 (Photo 2), Dustin Michelson (Photo 5), Ted King (Photo 8).

It’s hard to believe that the first Oregon Outback, that incredible 363-mile gravel race, was just five years ago. It’s almost like we live in a different world now, so much has changed…

Back then, the idea of running a race that traversed the entire state of Oregon from south to north – on gravel roads! – seemed completely outrageous. So seemed the idea of riding the entire distance non-stop. And the idea of riding a road bike on these gravel roads. More than one rider told me at the start that they were astonished to see me on my Rene Herse for this grueling event. I am sure Ira Ryan, on his Breadwinner B-Road, heard similar comments.

A joyful crew rolled out of Klamath Falls on Memorial Day weekend in 2014. Most were on mountain bikes equipped with bikepacking gear. Nobody knew what to expect. Would it take two days or a whole week to reach the Columbia River at the other end of the state? There were few options for bailout; there was no support – this was a real adventure.

It did not take long for the race positions to shake out. By the time we reached Switchback Hill (above), there were three riders at the front. Ira Ryan was the favorite, having won the Trans Iowa race in his home state. He was riding on 35 mm tires – which was considered wide! Another strong racer was on a mountain bike. He had opted for narrower 700C tires. I was on the widest rubber, with our just-released 650B x 42 Babyshoe Pass Extralights.

I couldn’t match the speed of the other two, not helped by a broken hand that was still in a brace… With almost 300 miles to go, I settled into my own pace.

As the day wore on and the ground got softer, I could see Ira’s tracks swerving wildly from side to side. There was only one set of recent tracks, so I knew that the second rider had abandoned by now… Even on my 42 mm tires, I was struggling. And yet, on the (even softer) edge of the road, I could see the tracks of two mountain bikers who had come through here a few days earlier. Their wide tires had enabled them to ride in a straight line…

A few hours later, I reached one of the three towns on the route, where I met Ira Ryan’s camera crew. I learned that he was just 15 minutes ahead. Even though I had struggled on the loose surface, I had made up a lot of time – simply because my tires were wider.

The solitude of the long day on the road gave me time to think. I remembered how the Paris-Dakar Rally had fascinated me as a teenager. I could see parallels to the Oregon Outback: In the early Dakars, competitors used 4×4 trucks, which seemed the best vehicles to traverse the deserts of northern Africa. Then Porsche developed a four-wheel-drive version of their 911 sports car and won the Dakar in their first attempt (above).

Here in the Oregon Outback, it was obvious that the wide tires of mountain bikes provided an advantage on very loose gravel. Yet it was also clear that the mountain bikes themselves were holding back their riders on what really were roads after all. For the Dakar, Porsche had allied four-wheel drive with sports-car performance. Could we do the same and combine the wide tires of a mountain bike with the performance of a road bike?

By the time I climbed Antelope Hill, I had a plan: We’d take our all-road bikes beyond the 42 mm-wide tires that we’d been riding until then. I was certain that ultra-wide road tires would transform our bikes’ performance on gravel and other loose surfaces.

The last miles of the race went by in a blur. When I saw that Ira had written “Go Jan!” into the gravel, I knew I was on the home stretch. (Thank you, Ira, for encouraging me!)

After losing much time in the middle of the night – I back-tracked for more than an hour to make sure that I was on course – there was no hope of catching Ira. (He was faster anyhow!) My goal now was to finish in 30 hours. I redoubled my efforts and let the bike fly on the descent to the Columbia River.

I made my goal – and took the photo above after realizing that there was nobody at the finish. But I also wondered how much faster (and more fun) the ride would have been on wider tires.

Back in Seattle, I went to work on making road bikes with ultra-wide tires. My only concern was that nobody had ever ridden supple road tires that wide. Would they even be rideable? Or would the wheels bounce down the road like basketballs? Before we invested in tire molds, we needed to test this. So I asked the engineers at Panaracer in Japan (who makes our tires) to make prototype tires with our Extralight casing, using a mountain bike tire mold. A few weeks later, eight completely hand-made tires arrived. Now we had super-supple knobbies, but we wanted road tires.

The next step was to send the prototype tires to Peter Weigle, the famous framebuilder and constructeur. Years ago, he built a machine to shave the tread off tires, before we offered wide high-performance tires with just the right amount of tread. Peter shaved off the knobs to turn our prototype tires into slicks (above). The result were probably the most expensive bicycle tires ever made, but now we finally had 54 mm-wide, supple, slick tires that we could test.

Alex Wetmore had a 26″ bike that fit tires this wide, his Travel Gifford. We borrowed it and installed the new tires. If you look carefully, you can still see where the knobs were on the prototype tire above. It’s hard to describe our excitement: We were about to try something completely new.

Then we started testing the new tires. On gravel, the 54 mm-wide tires were amazing. The bike just cruised over stuff that would have meant serious ‘underbiking’ on 42 mm tires. It was fun!

What surprised us even more was the new tires’ performance on pavement. The grip was just incredible, both because there was so much rubber on the road and because the soft, supple tires no longer skipped over bumps. On this difficult descent in Leschi, you usually have to be cautious and brake for the bumpy turns. With the new tires, we pedaled as hard as we could, yet we weren’t able to reach the limits of grip. Did I say the testing was fun?

Knowing that the ultra-wide road tires worked as well as we had hoped, we ordered molds for two new tires: the Rat Trap Pass 26″ x 2.3″ and the Switchback Hill 650B x 48 (above). Both were revolutionary at the time, by far the widest high-performance road tires anybody had made in more than half a century. (Some very early pneumatic tires had been quite wide, too.)

There were no road bikes yet for such wide tires, so we worked with Firefly to make us a custom titanium road bike designed around the 26″ Rat Trap Pass tires. We took it to 13,000 ft (4000 m) on the Paso de Cortes in Mexico (above), where it performed even better than we had hoped. (Testing the new tires was definitely fun!)

26″ wheels make sense for tires this wide, but the 650B wheel size had more traction at this point – that is why we introduced tires for both wheel sizes. The next step was obvious: Bike makers needed an inexpensive OEM tire before they could commit to making bikes for tires this wide. As a small company specializing in high-performance components, this wasn’t something we were equipped to do.

Fortunately, others were taking note of our pioneering work. In 2016, WTB launched its Byway tires. Now there were ultra-wide 650B road tires at OEM price points. Bike manufacturers were quick to act, and before long, almost every bike maker designed bikes around this tire size. Today, the size introduced with our Switchback Hill tires has become a new industry standard.

It’s hard to believe that all this started just 5 years ago, with the first Oregon Outback, that incredible 363-mile gravel race.

• Watch Ira’s movie of the Oregon Outback.
• Riding back from the Outback to Seattle via the Cascade Mountains.
• More information about Rene Herse tires.

With wide tires, you can tune the ride of your bike to the terrain and to your personal preferences. This gives you options that simply did not exist in the past.

Gone are the days when we inflated our narrow tires to the maximum pressure and rode on rock-hard rubber. Even with narrow tires, you can lower the pressure a bit to get a (slightly) more comfortable ride. Of course, there is only so much you can do – the feel of the bike won’t really change. There is simply too little air, and you’ll get pinch flats if you reduce the pressure enough to make a real difference. The only way to transform the feel of a racing bike is to get different tires – that’s why professional racers have always run hand-made tubulars with supple casings (well, at least since the 1930s).

With wide tires, supple casings also make a huge difference. In addition, you can choose your tire pressure over a wide range: The 54 mm-wide Rene Herse Rat Trap Pass tires that Hahn is running in the photo above work great at pressures between 20 and 55 psi. That means you can cut the pressure to almost a third of the maximum, if you want. (For comparison, this is like running narrow 120 psi racing tires at 45 psi. Don’t try this with 25 mm tires!)

With wide tires, you can tune the feel of your bike by adjusting the tire pressure. The same tire will feel completely different depending on how hard you inflate it. This is something that you really start to notice with tires that are wider than 40 mm.

At 55 psi, my Firefly with its Rat Trap Pass tires feels firm and buzzy like a road bike on narrow tires. There is no noticeable flex in the tires, no matter how hard you corner, or how fast you sprint. You’ll feel every detail of the road surface almost unfiltered. The extra air does take off some of the harshness, and the extra rubber gives you more grip, but the feel is similar to a bike with narrow, high-pressure tires.

Why doesn’t the 54 mm Rat Trap Pass feel wallowy like a 25 mm tire at 55 psi? If you think of the tire as an air spring – a piston in a cylinder – then pressure is only one factor. The other is the diameter of the air cylinder. To compress a 54 mm tire takes more force than to compress a 25 mm tire, even if both are inflated to the same pressure.

Even with wide tires, you can get the feel of narrow tires, if you inflate them to (relatively) high pressure. But you also have options to tune your bike by letting out some air.

At first, not much is happening – 55 psi is far more than most riders will ever want to use in these tires. At 30 psi, you still get the firm feel of a ‘road bike,’ but more shock absorption and even better traction. This is the pressure I ride on very smooth roads.

At 25 psi, the tire has a lot more compliance. Now it really feels like an ultra-wide tire. It still corners great, but you can go over bumpy roads and really feel the suspension. This is the pressure I use on most paved roads.

On rough gravel, I let out even more air. At 20 psi, the tire really floats over the gravel. This is how I imagine a rally car with ultra-expensive shock absorbers feels: ‘breathing with the surface,’ gently going up and down over bigger undulations, but insulating you from the smaller bumps and vibrations. It’s an amazing feeling, and, without the bike bucking under you, you can put down power at all times. It’s fun to ride at ‘road’ speeds on rough gravel.

And even at this low pressure, there is enough air to prevent the tires from bottoming out. Even with tubes, I don’t get pinch flats – unless the terrain is really rough and rocky and speeds are ultra-fast.

When you’re descending at very high speeds on very rough terrain, you’ll have to increase the tire pressure a bit to avoid bottoming out too often. Even if you run your tires tubeless, you risk cutting your tires and damaging your rims if you bottom out too often and too hard.

When you return to pavement, 20 psi isn’t enough. The tire starts to squirm and run wide in corners. When you rise out of the saddle, it feels wallowy as it compresses under the thrust of your pedal strokes. And if you really push the limit, the tire can collapse in mid-corner.

Back on pavement, I inflate the tires back to 25-30 psi. If my ride includes both pavement and gravel sectors in quick succession, I often just keep the pressure around 25 psi, so I don’t have to mess with it.

Tire pressure is not just about shock absorption – it also affects the power transfer of your bike. A frame that is too stiff for the rider’s power output and pedaling style is harder to pedal – a little compliance smoothes out the power strokes and allows the rider to put out more power. We call this ‘planing,’ but it’s hardly a revolutionary idea.

Usually, that compliance comes from the frame. That is why high-end, superlight bikes perform so well, even on flat roads where the weight doesn’t matter. The lighter frames use less material, which makes them more flexible. Conversely, ultra-stiff bikes can feel ‘dead’ and hard to pedal to many riders.

With wide tires, that compliance can come from the tires, too. When we tested the Jones (above), we found it to perform wonderfully with its tires at ‘gravel pressure.’ When we aired up the tires for a fast road ride, the bike suddenly felt sluggish. This is the opposite of what conventional wisdom might tell you, but when we lowered the tire pressure again, the wonderful performance of the Jones was back. This has nothing to do with rolling resistance – it’s all about how much power we could put out thanks to the added compliance in the system. The Jones ‘planed’ best with its tires at relatively low pressure. This means that you can use tire pressure to adjust how much ‘give’ you have in your bike’s power transmission. I’ve found this a useful tool to get the most out of many Bicycle Quarterly test bikes.

Speaking of rolling resistance – don’t tires roll slower when you let out air? At least with supple tires, tire pressure makes no discernible difference, not even on smooth roads. As long as you have enough pressure that the bike is rideable, your tires roll as fast as they do at higher pressures. And on rough roads, lower pressures will be faster, both because the suspension losses are reduced and because you can put out more power.

Tuning your tires is fun. It optimizes your bike for your preferences and for the terrain you ride. Of course, tire pressure first and foremost depends on your weight – the numbers in this post assume a bike-and-rider weight of about 80 kg (175 lb).

Tire pressure also depends greatly on the casing of your tires. The values in this post are for Rene Herse Extralight tires. With Standard or Endurance casings, you can run about 10% less pressure. With a stiffer casing, you run even less air, all the way to airless tires that run at zero pressure. As your tires get stiffer, you lose the ability to tune your ride, because air pressure plays a smaller role in supporting the bike-and-rider’s weight. The beauty of supple tires is that air pressure is the main component that holds up the weight of bike and rider. This makes it easy to tune your tires.

Rather than inflate your tires to a set number, experiment with tire pressures to see how this changes the feel of your bike. Also remember that the gauges on pumps aren’t always accurate – use them only to replicate a setting that you’ve found useful in the past, rather than try to inflate your tires to an exact pressure. Once you’ve found values that work, you can quickly change the feel of your bike based on where you’ll ride and how you want your bike to feel. This makes cycling even more fun!

Further information:

• Why high pressure doesn’t makes your tires faster.
• Why supple casings run at higher pressures and still are more comfortable.
• Information about Rene Herse tires

Our series of ‘Myths in Cycling’ continues with a look at rim width. It seems to make sense that wider tires should run on wider rims.

The idea is this: A wider rim makes a tire more U-shaped (left), rather than O-shaped (right) on a narrower rim. The sidewalls are more vertical, so they can better support the weight of the rider. This is said to make the tire flex less, so it corners more predictably.

When we first started experimenting with wider tires more than a decade ago, I was concerned: There weren’t any really wide rims available back then. I mentioned this to framebuilder Peter Weigle (above, in the center). His response surprised me: “I don’t think rim width matters. We used to race mountain bikes on narrow Mavic MA-2 road racing rims. I actually preferred how the bike handled with the narrow rims.” This came from the guy who won the cyclocross national championships on a mountain bike!

When I thought about what Peter said in the context of all-road bikes we were developing, it started to make sense. The extreme case of an O-shaped tire is a tubular: It’s perfectly round, and it touches the rim only at its very bottom.

And yet tubular tires are known for descending very well. Almost all pro racers in the Tour de France (above) ride on tubulars. If vertical tire sidewalls were essential for good handling, tubulars would have fallen out of favor long ago.

I realized that with supple tires, the sidewalls don’t really hold up the weight of bike and rider. It’s the air that supports the weight. And thus rim width doesn’t really matter. On my Firefly, I run 54 mm-wide Rene Herse Rat Trap Pass tires on 20 mm-wide (internal) rims without any problems (above). And the Firefly corners even better than a racing bike, because it has so much more rubber on the road. Like the pros, I never notice any squirm caused by the O-shaped tires.

When you look at the ETRTO chart for tire and rim compatibility, you can see that 54 mm tires on 20 mm rims are no problem. I could even go as low as 19 mm. (The values are internal widths in millimeters, and the ‘C’ stands for ‘crotchet’ rims.)

The chart shows that the real concern is at the opposite end of the spectrum: If the rim is too wide, tire pressure no longer pushes the bead strongly against the hook of the rim. This can cause the tire to blow off the rim. The ETRTO chart is quite conservative in this respect and recommends rims that are significantly narrower than the tires.

Together with other tire and rim manufacturers, Rene Herse Cycles is working on expanding the chart to include wider rims. In our experience, it’s fine to use wider rims as long as the internal width is at least 20% narrower than the tire. For my 54 mm Rat Trap Pass tires, this means that I can run them on rims somewhere between 19 and 40 mm wide. On wider rims, the tires will get a little wider, but even that doesn’t make a huge difference – we are talking maybe 2-3 mm.

What if you run stiffer tires? Would you want a ‘better’ match of tire and rim widths to take advantage of the sidewall stiffness? When I was at Paul Camp a few years ago, I got to ride a wonderful Steve Rex monstercross bike, shod with mountain bike tires (above). When I first rode the bike, the tires felt very harsh. I let out air until the bike began to float over the rough gravel in Paul’s parking lot. I loved riding the Steve Rex, and I pushed it harder and harder.

When we reached some really technical terrain, the front tire’s sidewall collapsed as the tire hit some rocks. It was very sudden, and more extreme than I had experienced when running supple tires at too-low pressures.

When Paul’s mechanic saw this, he checked my tires and shook his head: “You need to run about 30 psi in those tires!” Now 30 psi (2 bar) is more than I run in my Rat Trap Pass Extralights. Perhaps the mechanic was overestimating my weight, or adding a factor of safety, but it appears that when you ride really hard, tires with stiff sidewalls may need almost as much air as supple tires.

Relying on the tire sidewall for support has a disadvantage: Once the tire starts to flex, it bows outward (right). It goes from U-shaped to O-shaped. The more it bows, the easier it becomes to flex. Once it starts to collapse, it becomes less and less stiff, and there is little to stop it. This is called a ‘regressive’ spring rate. It explains why the collapse of the tire was so extreme.

Using air to support the bike results in a ‘linear’ spring rate. No matter how hard you push on the tire, the air pressure doesn’t change: It continues to push back with the same force. (In theory, the pressure goes up slightly as the tire deforms, but the tire’s volume is so large that this isn’t significant.)

Mountain bikers have found that the best shocks have ‘linear rate’ coil springs. ‘Progressive rate’ air springs are a second option for those who want to save weight (air weighs less than a coil spring). Nobody would ever suggest a regressive spring rate, yet that is what you get when you use the tire’s sidewall as a spring.

This suggests that you might even want to run stiff tires on narrow rims: The O-shaped tire will be easier to flex and thus more comfortable. Without the tire ‘standing’ on its sidewall, you’ll have to run a little higher tire pressure, but then you don’t have to worry as much about the tire collapsing. When Peter Weigle mentioned that he preferred the ride of wide mountain bike tires on narrow rims, I believe he was talking about this.

With a supple tire, this effect is magnified: With mostly air holding up the bike, the spring rate is very linear, and you can run a lower total spring rate – less stiffness of tire and air combined. That means you get a tire that absorbs shocks better and is more comfortable. And because the supple casing absorbs less energy as it flexes, it’s faster, too.

What this means in the real world:

• Rim width doesn’t matter for supple tires. You can run our widest Rene Herse tires on relatively narrow rims or on wide rims. There will be little or no discernible difference in how the tires feel and corner.
• Don’t use a rim that is too wide for your tires. The tire should be at least 20% wider than the rim.
• Using the tire sidewalls to hold up the rider results in a regressive spring rate. This can result in the tire collapsing suddenly.

Further reading:

• Why supple tires run at higher pressures, yet are more comfortable.
• The other posts of the ‘Myths in Cycling’ series.
• More information about Rene Herse tires.

We developed the Endurance casings for our Rene Herse tires based on requests from gravel racers like Ted King (above), who need tires for truly harsh conditions. A race like Dirty Kanza traverses 200 miles of sharp stones in the Flint Hills of Kansas. The lead racers travel at high speeds in densely packed pelotons, unable to see the road ahead – and thus unable to avoid hitting big and sharp rocks. The event becomes a race of attrition. If you flat and are lucky, your plug holds, your CO2 cartridge inflates the tire, and you can chase back on. More likely, you see the peloton vanish into the distance.

It’s for this type of event that we’ve introduced our Endurance casing. It’s a beefed-up version of our renowned Extralight casing: We use the same ultra-thin and ultra-supple threads, but push them closer together to obtain a denser weave. Then we add a puncture protection layer from bead to bead that reinforces not only the tread area against punctures, but also the sidewalls against cuts.

For even tougher conditions, we offer the Endurance Plus casing with thicker threads for even more cut resistance, plus the same puncture protection layer as the Endurance casing. It’s probably overkill for most rides and races, but there are times where you gladly give up a little speed for the peace of mind of not having to think about your tires at all.

We shipped a small quantity of Rene Herse tires with Endurance casings as soon as possible, so racers could use them in Dirty Kanza and other races. This also allowed us to get valuable feedback from the field.

Ted King (leading the pack in the photo above) rode the Hurricane Ridge Endurance Plus to a formidable 8th place in this year’s Dirty Kanza against international competition of professional riders. In the past, the ‘King of Gravel’ had suffered from flats in every edition of this epic race – but not this year.

Others had similar experiences. One customer wrote:

“I used the Steilacoom Endurance tires and had no problems or flats on the DK200 course this year. I did not feel that I had to brake and descend with extra caution, but felt confident to just let them roll. I will now continue to ride these tires, dropping the pressure for added comfort and better rolling resistance, and see where the limits are.”

Another racer commented:

“I would like to let you know on how amazed I was in yesterday’s Dirty Kanza riding your Steilacoom tires with the Endurance casing. Hassle free. No flats, no nothing, all good, and supple riding!”

And:

“Thank you for the expedited shipping so I got the tires in time for the race. You guys are as awesome as your tires…”

The first shipment of Rene Herse tires with Endurance casings sold out almost immediately. We’ve now received another shipment, and all models are back in stock.

We are also introducing two new models, the 700C x 44 mm Snoqualmie Pass Endurance and Endurance Plus with our smooth all-road tread. For dry rides and races where you won’t encounter mud, these tires are a great choice. They complement the knobby 700C x 42 mm Hurricane Ridge to offer a quiver of tires that will handle all conditions. They are ideal not just for racing, but also for adventures where you don’t know what you will encounter.

In addition to our Standard and Extralight tires, we now offer the following tires with Endurance and Endurance Plus casings:

• 700C x 38 mm Steilacoom knobby (Endurance)
• 700C x 42 mm Hurricane Ridge knobby (Endurance; Endurance +)
• 700C x 44 mm Snoqualmie Pass all-road (Endurance; Endurance +)
• 650B x 48 mm Juniper Ridge knobby (Endurance)

Click here for more information about our Rene Herse tires.

Photo credit: Dustin Michelson/Gravelguru (Photo 1).

Tubeless tires have changed what we can do on a bike. When the terrain is really rough, not having to worry about pinch flats allows us to run lower tire pressure for more comfort, more traction and more speed. (The speed comes from the lower pressure on rough surfaces, not from the tubeless setup itself.)

Setting up tires tubeless can be a hassle – and high-performance tires require more diligence yet. Everything that makes supple tires so fast and comfortable also makes them harder to set up tubeless: The ultra-thin sidewalls aren’t air-tight, and the tires are so floppy that the bead can be hard to seal against the rim. Supple tires need sealant to close those microscopic pores in the casing and to constantly seal the tire against the rim.

There are many tricks to setting up tires tubeless, and the right choice of sealant is one of them. Many sealants are intended for mountain bike tires with stiff casings that are covered with a thick layer of rubber, making them airtight on their own. The sealant is only intended to close small punctures, not to make the tire itself airtight and seal it against the rim. Those sealants can work OK with supple high-performance tires, but we wanted a better solution.

Over the last two years, we’ve worked with Panaracer in Japan to develop a sealant that is specifically formulated for the supple sidewalls of Rene Herse tires. (The sealant works equally well with Panaracer tires and other brands.)

The Seal Smart sealant uses natural latex and walnut shells to make the tire airtight and seal it against the rim. Thanks to these ingredients, it’s non-toxic and low in allergens. Clean-up is easy, too.

Most of all, it works really well. With every tire we’ve set up so far, the tire sealed almost instantly and held its air for weeks without re-inflating. We’ve tried it on tires that were returned under warranty because the sidewall didn’t seal. (This happens very rarely when the rubber coating is a bit too thin.) Bubbles appeared on the casing, and the tires continued to lose air. With the new Seal Smart, two tiny bubbles appeared at first, but the tires sealed fine. We wiped off the bubbles, and they didn’t reappear – the tires were ready to ride.

Of course, every installation is different, and we cannot guarantee a successful tubeless installation. Especially with supple tires, it pays to be extra-diligent when distributing the sealant inside the tire to make sure it goes into every crack. And make sure to shake the sealant vigorously for a minute or more to distribute the solids really well: If you’re just injecting white water into the tire, it won’t seal…

The new Panaracer Seal Smart comes in 1 liter bottles – enough to set up multiple tires and replenish your sealant frequently. It is in stock now.

Further information:

• Rene Herse tires and Panaracer sealant
• Tips for setting up tires tubeless
• Why tubeless tires aren’t faster than tubes

How fast are our tires? We know that the casing, and not the width, determines a tire’s speed. When I rode Paris-Brest-Paris on 42 mm-wide tires (above), I knew that I wasn’t giving up any speed over narrower rubber. But in absolute terms, how fast are our Rene Herse tires?

Manufacturers’ claims always are taken with a grain of salt… So let’s look at two independent tests of our tires. They still list the old ‘Compass’ name, but the tires tested were the same as the current Rene Herse models.

The respected German magazine TOUR found our Bon Jon Pass as one of the five fastest tires they’ve ever tested. TOUR tested the Standard model. The much more supple and speedy Extralight would have fared even better.

TOUR’s test rig is a pendulum that rolls the tires back and forth. The longer the pendulum swings, the lower the rolling resistance.

Like all tests that don’t include a rider, this test measures only losses due to deformation of the tire (hysteretic losses). In the real world, there are also suspension losses as vibrations are absorbed by the bike and the rider. Wide tires vibrate less than narrow ones, so they tend to roll even faster than these tests suggest.

In any case, the result is clear: In TOUR’s test, the Bon Jon Pass is one of the fastest tires in the world, closely matching the best racing tires. Being 9-12 mm wider than the racing tires doesn’t make the Bon Jon Pass any slower.

What’s the best gravel tire? – 10 models in comparison

How about comparing our tires to other wide tires? Gran Fondo magazine recently tested ten popular gravel tires. Rolling resistance (and puncture resistance) were tested by Schwalbe’s engineers in the company’s test lab.

Our Barlow Pass Extralight had the lowest rolling resistance (red bar) of all tires in the test. (100% is the best in the test.)

The engineers at TOUR and Schwalbe are among the most respected in the cycling world. Their tests show that our casings are among the most supple, and roll as fast or faster than the best tires in the world.

On real roads, the advantage of supple tires is even greater: Not only do they absorb less energy as they flex, they also vibrate less. And that reduces the suspension losses. Both effects work in tandem: Supple tires have less tire deformation and less vibration. As a result, the greater speed of supple, wide tires becomes very noticeable when you ride on real roads. When you try different tires back-to-back, you realize that tires are the biggest performance upgrade you can make to your bike.

A little more about the Gran Fondo test: The testers were impressed by the “superb levels of comfort” of the Barlow Pass and called it “almost as nice as flying.” They also were surprised how much grip the supple tires offered on gravel and dry dirt roads. Of course, reading that makes us happy, even if it just confirms what we’ve found in our own testing.

Further reading:

• Click here to read the full Gran Fondo article.
• Click here for more information about Rene Herse tires.

Autumn means colder temperatures and rainy weather, here in the Cascade Mountains and in many parts of the world. More than ever, the grip of our tires is on our minds. Why do all Rene Herse tires have black tread? Colorful treads can look nice, but black rubber offers the best grip.

That is one reason why all car tires today are black. In the early days of motoring, tires were made from natural rubber, which is white or gray. (That is why the famous Michelin man is white…) By the 1910s, it was becoming apparent that white rubber didn’t last well, and tire makers discovered that adding carbon black to the rubber made it last much longer. As a positive side effect, it increased the tire’s grip, too – and it made the tires black. Even today, you can get car tires in many colors, but they are considered a novelty and not intended for daily use, much less for performance driving.

It may come as a surprise that the color of rubber and plastic affects many other properties, too. For example, gray resins are stronger than black or colored varieties. That is why the frames of Berthoud saddles are gray. With rubber, blue appears to be the least durable – which is why the blue hoods for old Mafac brake levers are almost unfindable today. And red backpacks fade far more quickly than other colors…

The reason is simple: Colors are additives, and often, surprisingly large amounts of the colorants are needed to create the color. This often changes the physical properties of the raw material. The black color of tires works the opposite way: Carbon black is an additive chosen for its performance-enhancing properties, and it just happened to change the color to black.

Before we made our Rene Herse tires, we rode tires from many makers. When I was racing in the 1990s, Vittoria introduced their ‘Professional All Weather’ model with softer green rubber on the shoulders. This was supposed to be grippier when leaning the bike into wet corners. It seemed like the perfect tire for Seattle’s infamous rainy season.

We tried the ‘All Weathers,’ and immediately scared ourselves: They seemed to grip fine at first, while we were still riding on the black center tread. Leaning further, grip was lost very suddenly as we transitioned to the green rubber. Then TOUR magazine did one of their famous tire tests. They measured tire grip on wet roads and confirmed that the ‘All Weather’ was less grippy than Vittoria’s standard, all-black tires! We never found out what the Italians were thinking when they developed these tires. I recall a big marketing push with all kinds of colors around that time, but it didn’t last long. Today, all Vittoria tires have black tread again.

Later, we imported the first supple, wide 650B tires from Japan. Made to resemble classic French rubber, the first model was available only in red and white. We loved the supple casings, but we found that in the wet, the white version was noticeably lacking in traction. Riding the red model, we also felt the grip bleed away earlier than we expected. We requested a special run of tires with black tread, and those gripped much better.

Of course, black tread alone isn’t a guarantee for excellent traction. I recall one tire from a small company that would spin when accelerating from a stop on cold, wet (but clean) pavement. Clearly, not all rubber is made equal.

When we first talked to Panaracer in Japan about the tires we wanted to make, they showed us many beautiful colors. There was a very attractive tea green… When we asked about the performance, the engineers left no doubt: “Black has the best grip.” What about the colored treads? “It’s all about fashion. It allows small companies to offer tires that are different from the mainstream.”

There is nothing wrong with fashion, but for us, performance is more important. On the steep, twisty descents of the Cascade Mountains, we need tires that grip. And fortunately, Panaracer’s top-level tread rubber is among the grippiest you’ll find anywhere.

Of course, there is much more to making a tire grip than just the tread compound. Our herringbone tread pattern has many ribs that interlock with the road surface. When we tested the herringbone tread back-to-back with slick tires, the difference was very noticeable. A supple casing also grips better because it keeps its tread in contact with the road surface. A stiffer tire will bounce more and have less traction. For our Rene Herse tires, we’ve optimized all these parameters to offer you tires with more grip than just about any other tire – on dry and wet roads.

Even with the best tires, riding in Autumn and Winter requires extra caution. There are many factors that decrease traction when it’s wet and/or cold:

• Cold rubber is less grippy – your traction is reduced when the temperature drops. This is quite significant, especially once the temperature drops below 10°C (50°F).
• On wet roads, tread patterns that interlock with the road surface offer the greatest benefits. With the right tires, you can lean quite far into corners (top photo) – if the asphalt is clean.
• After the first rain, the water mixes with dust, oil and other airborne pollution to form a very slippery surface layer. Use extreme caution when it hasn’t rained in a long time.
• Your tires stay wet for a while after you ride through water. Remember this when you cross a wet patch on the road: Your tires may still be wet in the next corner, even if the road surface there is dry.
• Painted traffic markings on the asphalt can be very slippery in the wet. Metal surfaces – grates, manhole covers, railroad tracks, plates covering trenches at construction sites – are even worse. Avoid them if you can. If you must ride over them, straighten your bike before you reach them, so you aren’t leaning while you are on the slippery surface.
• Scan the road for shiny oil that has dripped from cars with leaky crankcases.
• Tire sealants that use latex – which means most brands – won’t seal when it’s cold. (Latex doesn’t cure well when it’s colder than 10°C/50°F.)
• Snow and ice require special considerations.

We enjoy riding our bikes year-round, so we’ve developed components that perform well in wet and cold conditions, not just when it’s dry and warm. With the right equipment and skills, riding in all weather can be safe and enjoyable.

Further reading:

• Why a herringbone tread provides more traction.
• More information about Rene Herse tires.

P.S.: I apologize for re-using the same opening photo. There aren’t many that show us cornering hard in the rain – when it’s wet and cold, we prefer keep going to stay warm, rather than stop for photos!

We like Road.cc, the British web site, because they really ride the products they test. They’ve got a number of testers, and their opinions are refreshingly unbiased and honest. At the end of each test, they ask their reviewers “Would you buy this product?” and “Would you recommend this product to a friend?”

Recently, they reviewed our Juniper Ridge dual-purpose knobbies, and tester Stu Kerton replied “Yes” to both questions. His summary explains why:“The Juniper Ridge has been designed to work just as well on the road as it does off the beaten track. I was sceptical, but to be honest they are pretty good, giving a boost to your average speed on those tarmac sections between the tracks and trails.”

Grip on gravel and in mud impressed him, too: “Cornering on hard-packed gravel, the Junipers had just the right level of grip for the knobbles to dig into the gravel so you could blast round at speed. […] They grip well on soft mud and the tread doesn’t seem to hang onto any dirt either, shedding it before it can become compacted between the knobbles. The only place they did suffer a bit was on wet, sticky chalk, which could clog up the tread.” But then, I suspect that any tire will clog up in that type of sticky mud…

It’s exciting when testers enjoy our tires as much as we do. Rather than tell you more about the test, why not read the full review for yourself at road.cc?

Rene Herse tires are available in many widths, with two tread patterns and four casings. All this so you can find tires that are ideally suited to how and where you ride. Today, let’s look at the different casings. Which is best for you?

Our standard casing is the workhorse of the Rene Herse tire program. It features the supple casing that has made our tires famous. That means it’s comfortable and fast, yet it’s also strong to withstand considerable abuse. It’s the tire most of our customers choose, and it’s also our most economical one. You can’t really go wrong with the Standard casing.

The Extralight casing is our ultimate: Ultimate in speed. Ultimate in comfort. Ultimate in light weight. It’s an extremely fine and supple casing that you’ll otherwise find only on hand-made tubulars. Riding the Extralight will make you fall in love, and riding your bike will never be the same.

All that supple performance makes the Extralight’s sidewalls a bit more fragile. If you scrape along rocks (or curbs), the sidewalls will abrade or cut more easily than other tires. Is that a problem? Not if you’re running tires that are wide enough for your terrain, and if you ‘ride light’ on your bike. Descending Japan’s highest pass road (above), I took the bike to the limit, yet my Extralights were none the worse for wear. If your daydreams revolve around supple tires, then these are the tires for you.

We’ve developed the Endurance casing for gravel racing. When you are riding in a peloton at 30 mph, you can’t see where you are going, and you’ll hit big rocks at high speed. In that situation, you’ll give up a little speed for extra sidewall protection. Because gravel racing is first and foremost a race of attrition: To win, you need to be in the lead group when you approach the finish!

The Endurance casing uses the same extra-fine thread of our Extralight, but pushes them closer together for a denser weave. It also adds a protection layer on the sidewalls and under the tread. Both greatly increase the resistance against punctures and abrasion. It makes the tires easier to set up tubeless and works better with hookless rims, too. If you’re heading into the Flint Hills of Kansas to get dirty in the front pack, you’ll want your rims shod with Endurance rubber.

The Endurance Plus casing is a totally different animal from our other tires. It uses thicker threads for even more strength and resistance against cuts and abrasions. It has an even stronger protection layer on the sidewalls and under the tread. If the Superlight casing is the sportcar among our tires, the Endurance Plus is the off-road racing truck. It’s as tough as it gets, yet still as fast as possible.

This is your tire when you are heading into the unknown. If you’ll plunge into deep rivers during the Rift Iceland (above) or traverse the mountain ranges of Kyrgystan, the Endurance Plus is designed for you.

Which tire is right if you mostly ride pavement? Both the Standard and Extralight casings work great on the road. They entice you to seek out scenic lanes with little traffic. They filter out the rough pavement that hasn’t been replaced in decades. The Standard casing will make you smile with every mile. Riding the Extralight, you will make you understand why generations of pro racers have used handmade supple tires, even if they have to buy them with their own money.

If you have to ride on the shoulders of busy highways or in the gutter of city streets, glass and little steel wires will be your enemies. If you get too many flats, the Endurance casing is your friend.

Whichever casing you pick, you’ll enjoy the speed, comfort and grip for which Rene Herse tires have become famous. You’ll be surprised how much of a difference a great set of tires makes. You’ll fall in love with your bike all over again!

Click here for more information on Rene Herse tires.

Photo credits: Natsuko Hirose (Photo 3), SBTGRVL (Photo 4), Ansel Dickey (Photo 5), Donalrey Nieva (Photo 7).

You asked for it… Many customers requested our Barlow Pass with the Endurance casing. It makes sense – 700C x 38 is a versatile size. If your rides are littered with glass, steel wires or goatheads, the Endurance casing is going to be your friend. You get a tire with much of the speed and comfort of our other Rene Herse tires, yet it’s considerably tougher than the Standard or Extralight casings.

The Antelope Hill is another prime candidate for the Endurance casing. Call it 700C x 55 or 29″ x 2.3″ as you wish – it’s a tire for monstercross and mountain bikes that are ridden on gravel roads (and paved ones, too).

Most of the time, the sheer volume of this tire (and associated low pressure) will ward off sidewall cuts and punctures. Yet by their nature, the Antelopes invite you to take them places you wouldn’t go otherwise. And then the extra protection of the Endurance casing can be great reassurance…

These Rene Herse tires are available with Endurance casings:

• 650B x 48 Juniper Ridge (knobby)
• 700C x 38 Barlow Pass
• 700C x 38 Steilacoom (knobby)
• 700C x 42 Hurricane Ridge (knobby)
• 700C x 44 Snoqualmie Pass
• 700C x 55 Antelope Hill

Quantities of the new models are limited for now, until production catches up with demand. Click here for more information.