Making Strong and Durable Wheels

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When building a bike, one important decision concerns the wheels. How do you get the best performance and still make your wheels strong enough to withstand 20,000+ miles of riding on rough roads without needing service?

By now, most cyclists know that spokes don’t break from overloading, but from fatigue as the spoke is loaded and unloaded when the wheel rotates. The wheel flattens at the bottom, which unloads the spoke at 6 o’clock. With each wheel revolution, every spoke passes through that spot, where it is slightly detensioned, and then tensioned again. Over time, that causes the spoke to fatigue.

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To get the maximum life out of your spokes, you want the detensioning to be as small as possible. That is what double-butted spokes (above) are for: They are thinner in the middle, so they can stretch more, which means that they don’t detension as much as a thicker spoke would. Yet the ends, where spokes fail if they break, are thick and thus will last a long time. It may seem counterintuitive at first, but the thinner mid-sections make double-butted spokes more durable than thicker straight-gauge spokes.

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Wheels tend to go out of true when you hit a bump and a spoke detensions so much that it goes slack. As the spoke is tensioned again, the nipple unwinds a bit. Now the spoke has less tension, so it will go slack more often, allowing the nipple to unwind more and more… For more information about the basics of wheel building, I recommend the late Jobst Brandt’s excellent book The Bicycle Wheel.

Now, let’s look at the specifics of building a strong wheel.

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How many spokes do you need? For many years, 36 spokes was the standard (above), then it became 32 as modern spokes became stronger. On my René Herse (top photo), I use a 28-spoke front wheel. I built the wheel six years ago and never touched it again. If the rim hadn’t cracked (different story!), I am sure it would still be going strong today.

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We can use fewer spokes, because the wider tires we ride today transmit far fewer shocks to the rim. Imagine hitting the bump above with a 23 mm tire: Even if you don’t bottom out, your tire is so hard that much of the impact will be transmitted to the rim. The big, soft tire not only transmits less shock to the rider, but also to the rim.

With smaller 650B or 26″ rims, the spoke bracing angle is greater, which makes the wheel stronger as well. That means that 28 spokes are plenty, even for rough roads.

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However, the SON Delux hub I usually ride on my Herse has very narrow flanges, which results in a smaller spoke bracing angle, negating the benefits of the smaller 650B rims. For the Oregon Outback 363-mile gravel race, I put on a wheel with an old SON20 generator hub that has wider flanges (above). When you negotiate rough terrain, your wheel can slip while it’s pointing sideways, then suddenly catch and regain traction. If the wheel is not strong enough, it can collapse into a potato-chip shape, and your ride is over.

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We wanted a wider spoke bracing angle, so we asked Schmidt Maschinenbau for the Wide-Body Delux hubs, which have the widest flange spacing possible and thus build into the strongest wheels. Compass now offers these hubs in 28 holes, in addition to the 32h and 36h that have been available for a few years. If I had a Wide-Body hub on my bike, I would have been perfectly happy with 28 spokes for the Oregon Outback.

shimano_disc_blogThere are cases when a front wheel with more than 28 spokes makes sense. With disc brakes, your flanges are more narrowly spaced to make room for the rotor – that is why there is no Wide-Body Disc hub – and the entire force of braking is transmitted by the spokes. In this situation, a 28-spoke wheel usually is OK, but 32 spokes gives you an additional margin of safety. The same applies for 700C wheels (larger-diameter rims result a smaller spoke bracing angle), or for very heavy bike/rider combinations. For tandems, I’d go with 36 spokes.

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Compass offers the excellent SON Delux Wide-Body hubs with 28, 32 and 36 holes, so you can choose the spoke count that is right for you. We also offer the Delux for disc brakes with 32 holes, both in quick release and thru axle versions (above).

What about the rear wheel? Here, too, the answer is: “It depends.” If you have a strong rim, then 28 spokes may be enough. When HED send us test wheels with their Belgium rims a few years ago, they used 28 spokes front and rear, and they held up fine even when we rode them on mountain bike trails. One reason is that the rear wheel never sees significant side loads.

However, the rear wheel has a much narrower spoke bracing angle to make room for the freewheel/cassette. That is why British builders often used rear wheels with 4 or 8 more spokes than the front. I did the same on my René Herse, which has 36 spokes on the rear. Most wind tunnel studies indicate that the rear wheel is in such turbulent air that its aerodynamics don’t matter much, and the little extra weight isn’t a big deal, either.

Next, let’s talk about rims: Most rims today are stiff and strong. If rims crack, it’s usually caused by poor design or sub-standard materials. Once you’ve eliminated those problems, what you want from your rims is a good fit of the tires. With classic rims, it needs to be good enough to seat the tire automatically as you inflate it. And the tire shouldn’t come off even if you have a sudden blowout on the front. With tubeless-ready rims, the fit needs to be even more precise, so the tire seals easily and doesn’t blow off the rim despite lacking a tube that reinforces the joint between tire and rim.

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Compass offers three rims:

  • The Grand Bois rims are a proven classic, available with 36 holes. The polished finish is beautiful, and the tire fit is very good. However, they aren’t compatible with tubeless mounting.
  • The brand-new Pacenti Brevet rim combines classic appearance with tubeless-ready construction. Compass has them in stock in 28 and 32 holes.
  • The HED Belgium Plus is a modern, lightweight, wide semi-aero rim. It is tubeless-compatible, with a tire fit that is consistently excellent. A few of us have been riding them for a few years now (above Theo’s bike), with zero need for truing and easy tire mounting. Black anodized and available in 28 and 32 holes for rim brakes, and in 32 holes for disc brakes.

For each of these rim/hub combinations, we now offer spoke packages with the highest-quality, double-butted, superlight Sapim Laser spokes (2.0 – 1.5 – 2.0 mm) and aluminum nipples. That makes it easy to build a generator hub wheel that is perfect for your intended use: Just select your hub and your rim, and then order the spoke package that goes with this combination. (We also offer the spokes individually.)

Click here for more information about Compass wheel goods.

Posted in hubs/rims, Lighting | 52 Comments

Panaracer: Hand-Made Tires

A highlight of my visits to Japan is going to the Panaracer factory. It’s a magical place, where some of the world’s best tires are made largely by hand. It resembles a storybook factory: Huge machines emit hissing steam. Skilled hands assemble casing, beads and tread. Hot tires cool as they move along conveyors under the roof.

The main reason for my visits to the factory is to discuss ideas for new tires, and improvements to existing ones, with Panaracer’s engineers (above). These guys know more about making bicycle tires than almost anybody in the world. We bring them our ideas, they provide feedback and input, and together, we finalize new designs, like the innovative tread pattern of our Steilacoom knobbies.

During recent meetings, we’ve been talking a lot about tubeless tires. Tubeless is an emerging technology without real standards yet. We must figure out how to make tires that work on as many different rims as possible. When customers have problems, we try to diagnose and troubleshoot for them. We all share the goal of making the most of this exciting new technology.

Once we have finished our meetings, we often get to walk around the factory. Two weeks ago, we saw our Steilacoom, Switchback Hill and Snoqualmie Pass tires being made. It was the first time that my visit coincided with one of our production runs – great fun!

There is nothing really toxic involved in making tires at this factory – just steam and heat – so there is no need for protective clothing, not even earplugs. (Like many Japanese, the worker below wears a face mask for protection against spring-time pollen, not industrial pollution.)

Making tires starts with kneading the hot tread rubber in huge machines that look like they belong in a giant bakery. The rubber is rolled into thinner and thinner strips, until it has the right thickness for the tread.

The casing is stored in huge rolls, ready to be impregnated with rubber. Both the thickness of the threads and the amount of rubber coating determine how supple the tire will be. This is where the experienced workforce and time-tested machinery allows Panaracer to go a few steps further than most tire makers and use ultra-fine fabric and a very thin rubber coating to make the lightest and most supple tires possible.

The tires are assembled by hand. It’s a fascinating process, and I could easily spend a month photographing the factory. There is enough material write a book! But there are too many trade secrets, so no photography is allowed. Panaracer’s engineers would prefer if nobody knew what is going on in their factory.

Ever since I first visited this amazing factory, I’ve wanted to show our readers how high-end tires are made. It took us years to persuade the company to do a photoshoot last year. Each photo was carefully vetted before it was cleared for publication in Bicycle Quarterly. Knowing this, I feel incredibly privileged to be allowed to see everything and ask questions about anything when I am visiting.

Once assembled, the raw tires look almost like the finished product (above), but they are only loosely assembled. They still lack their tread pattern, too. All this comes in the next, most impressive step…

Each tire is vulcanized (above). That means it is placed in a mold that is engraved with the tread pattern. Steam heats the mold until the rubber partially melts. The tread rubber flows into the mold and is imprinted with the tread pattern. Since the tire partially melts, all its elements are fused together and become inseparable, making the tire very strong. When the tire emerges from the mold, it is no longer flat, but has the domed shape of, well, a tire. After it cools, it’s ready for quality control and packaging.

In the past, vulcanized tires were considered slow, and hand-glued ones were faster. That was because the casing material used in the factories that vulcanized their tires was stiff and not optimized for performance. With all tires, the casing is by far the most important factor that determines the tire’s performance and comfort.

Panaracer’s high-end tires use very supple casings, yet they are vulcanized. This combines the best of both worlds – the naturally round shape of the tire further optimizes the tires’ performance: As the wheel rotates and the contact patch leaves the ground, the tire automatically resumes its round shape.

Many hand-made tires are not vulcanized. Held together with strong glue, they look like the raw tires in the photo above – flat. When their contact patches leave the ground, tire pressure has to overcome the tire’s natural flat shape to make it round again. According to Bicycle Quarterly‘s testing, this makes the tire about 3% slower.(1) The very best tubular tires, such as those made by FMB, are assembled on an inflated casing. That way, the tire has the same round shape as a vulcanized tire. Why aren’t all tires vulcanized? Small makers don’t have the machinery that is required.

For the Compass Extralight models, Panaracer uses a casing usually reserved for their top-end racing tubulars. Panaracer doesn’t use this casing on their own clinchers. The company feels that their tires may end up with inexperienced customers, who may need sturdier tires.

We are glad that Panaracer’s engineers are willing to push the envelope a bit further for our Compass tires. We are confident that Compass customers try to avoid crashing into potholes and obstacles that could ruin a high-performance tire. In any case, the limits of what supple tires can do are quite high – witness the photo above showing a set of Compass Extralight tires in action. The tires survived the long and rough descent from Odarumi Pass in Japan without damage.

I cannot show you the factory, but if you are going to the North American Handmade Bicycle Show (NAHBS) in Salt Lake City, Utah, this weekend, you’ll be able to meet the people from Panaracer. Stop by their booth and tell them how much you enjoy the tires they make for us!

The full report on the Panaracer factory was published in Bicycle Quarterly 58. If you missed that issue, it’s available as an individual back issue or with our 4-pack of the last year’s Bicycle Quarterlies.

Click here for more information about Compass tires.

(1) We tested two tires made with the same casing and tread. One was assembled on an inflated casing, the other “flat-glued”.

Posted in Tires | 42 Comments

Mountain Cycling Club Hillclimb Race

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Tokyo’s Mountain Cycling Club reminds me of the Groupe Montagnard Parisien: almost unknown, yet fascinating and influential far beyond their limited membership. The French riders brought us the Technical Trials and modern randonneur bikes, while their Japanese counterparts co-invented mountain bikes.

The Mountain Cycling Club started exploring the mountain passes in the Japanese Alps decades ago. For their incredible rides on single-track or even hiking with their bikes on their backs, they developed “Passhunter” bicycles: wide tires, derailleurs, flat handlebars and cantilever brakes… meeting all the definitions of what makes a mountain bike.

Around the same time, Gary Fisher, Joe Breeze and all the others in Marin County started putting derailleurs on their “Klunkers,” so they could go up, and not just down the mountains. I’m still learning about Passhunters, but it’s clear to me that they were initially designed to go uphill, whereas mountain bikes started with the idea of going downhill… Imagine if the Japanese riders had been as ambitious in marketing their ideas as their Californian counterparts – mountain bikes might look quite different today!

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Natsuko has been a member of the Mountain Cycling Club for many years, and she introduced me to the club. Every year in late February, the club organizes a hillclimb race. That is why last weekend, we left central Tokyo at sunrise with our bikes in their Rinko bags and headed into the mountains by train.

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We assembled our bikes and rode to the start. The race goes up a pass that climbs more than 700 m (2300 ft) in about 8 km (5 miles). The road is paved, but this early in the season, there often is snow on the upper reaches. As you’d expect from the Mountain Cycling Club, this isn’t an ordinary race!

Riders show up on a variety of machines. This winter hasn’t seen much snowpack, and conditions were rumored to be dry, so two riders came on carbon-fiber racers. Others had brought cyclocross bikes, like this lovely Amanda (above), in case there was snow after all.

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And then there were purpose-built machines like Makio-san’s old Toei, with 650A wheels, cut-off randonneur handlebars and low gears. This machine exists only to climb hills as fast as possible.

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At 11 o’clock, we lined up for the start. We could see the pass in the distance, looming high above and doing its best to intimidate us.

As the club has aged, there aren’t as many racers as in the past, but those who came were serious about the task ahead. In fact, two participants weren’t members of the club, but racers who had come just to measure themselves against the mountain. Natsuko, who was the only woman, had started 15 minutes earlier together with the oldest rider…

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The first few kilometers were on a moderate gradient, and the group rode together to warm up. Then the valley steepened, the road narrowed, and the race began in earnest.

Obviously, I didn’t have time to take photos while racing… I got a good start and opened a small gap on a short downhill section – the only one on the course – but then the two racers reeled me in relentlessly. As the road steepened to about 18%, I struggled as they caught me. Knowing the course, they accelerated before a sharp turn after which the gradient relented a bit. I didn’t have the legs to stay with them, and they vanished into the distance.

The course was un-marked, and twice, I reached forks in the road not knowing which way to go – until I heard the organizer’s trumpet from above. It was a very romantic way to guide me and the other racers in the right direction.

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After a final sprint to the top, I finished in 54 minutes and a few seconds. The winner was an impressive 4 minutes faster. When I arrived, he and the second-place finisher already were eating Oden soup that the organizer had cooked on a camping stove. Makio-san on his Toei hillclimber came fourth.

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One by one, the riders arrived. We enjoyed gorgeous views and lively conversation. Unlike most “real” races, this unsanctioned event had a great mix of competition and camaraderie.

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To cool down, I went across the pass. The other side was in the shade, and there, I did encounter snow and ice. Now I believed the stories of running through the snow, cyclocross-style, on the upper reaches of the climb.

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There was a brief awards ceremony – Natsuko was the fastest (and only) woman, while my third place made the fastest member of the club. Clouds were covering the sun, and it was getting chilly so high up in the mountains, so we headed back down.

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Only then did I realize how steep this road really was. The descent was twisty, technical, very fast, and great fun. When we reassembled at the bottom, everybody agreed that it had been a great day. I can’t wait until next year. Hopefully, I’ll be in Tokyo again for the race. Now that I know the course, perhaps I can improve my time?

Posted in Rides | 4 Comments

Berthoud Saddles and Bags

theo_bikeWe’ve been fans of Gilles Berthoud saddles and bags for many years. Above is Theo’s bike with Berthoud GB28 bag and Aspin saddle. These parts have been incredibly durable: I still use the very first Berthoud handlebar bag that he bought 17 years ago, and the prototype Berthoud saddle on my Urban Bike is still going strong after a decade of hard use. There simply aren’t better-quality or higher-performance bags and saddles anywhere.

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We’ve recently added Berthoud saddles to the Compass-exclusive bags we’ve been selling for years. Leather saddles have long offered the ultimate in comfort for long-distance cycling, because they shape themselves to your unique anatomy. Gilles Berthoud wasn’t satisfied with other leather saddles, because quality had declined over time. Most companies now try to get as many saddles as possible from each hide, without regard for irregularities and direction of grain. So, he decided to make his own saddles.

Berthoud saddles start with the best vegetable-tanned cow hides, which are dyed in-house. Each saddle top is then cut in the direction of the leather grain. While this results in fewer saddles from each hide, it ensures that the saddle doesn’t sag. The remnant leather is used to make fender washers and other small parts, so there isn’t any wasted material.

The leather is thick and initially firm, but Berthoud saddles are comfortable out of the box due to their excellent shape. Pre-softened to shorten the break-in, they will last many years with occasional treatment. (We recommend Obenauf’s leather treatment, which we now also carry.) Berthoud saddles rarely need tensioning, but when they do, all you need is a 5 mm allen key.

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Gilles Berthoud’s saddles use thoroughly modern materials and construction methods, while maintaining the advantages of a tensioned leather saddle. The composite frame is stronger than steel and absorbs shocks better. Berthoud placed the bolts outside the sitting area, sparing your cycling clothes from snags and abrasion. We’ve been riding these saddles for years and appreciate their quality and re-buildable design – every part can be replaced.

Compass offers three models of Berthoud saddles: the Aspin, Aravis and Galibier. Each is available in tan, (dark) brown, black or Berthoud’s distinctive cork finish (below).

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The Aspin (shown above) is a high-performance leather saddle with a medium width – designed for an intermediate riding position that most cyclists find comfortable over long distances. Named for the 1,489 m (4,885 ft) Col d’Aspin in the Pyrénées, the Aspin uses Stainless Steel rails for strength and affordability. The Aravis saddle, named for the 1,487 m (4,878 ft) Col des Aravis in the Alps, combines the same shape with ultralight titanium rails for lighter weight.

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Berthoud’s lightest high-performance saddle combines a narrow shape with titanium rails for a weight of only 346 g. Named for the 2,645 m (8,677 ft) Col du Galibier in the Alps, this saddle is designed for spirited riding in a stretched-out position, yet features the same thick, luxurious leather upper as Berthoud’s other top-quality saddles.

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Berthoud is best-known for their beautiful and functional bags. Handlebar bags place supplies within easy reach while riding, and keep your map, or cue sheet, in view. On a bike with suitable front-end geometry, they affect the handling less than a rear load.

In the early days of randonneuring, Sologne pioneered what we now consider the classic handlebar bag. When Sologne went out of business, Gilles Berthoud bought the patterns and know-how, so that these classic handlebar bags remain available today. With more than 50 years of experience, their bags are sewn in France from cotton and leather. While we love their classic appearance, we use Berthoud bags mostly for their superior performance: They are lighter and more waterproof than most “modern” bags.

Based on our decades of riding with Berthoud bags, Compass asked Berthoud to make small improvements to the “Compass-exclusive” bags: All our bags have shoulder straps, and we offer them also without side pockets for better aerodynamics and even-lower weight.

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We also offer Berthoud’s panniers with classic leather straps and springs for an ultra-secure mounting that doesn’t rattle against your rack (above).

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We sell these Berthoud products directly to our customers, and we now also wholesale them to bike shops who carry the Compass product line. If your local shop doesn’t have an account with us yet, please put them in touch.

For our complete line of Berthoud saddles and bags click here.

Posted in Product News, Racks/Bags | 30 Comments

Compass Centerpull Brakes for Bolt-On Mounting

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We now offer Compass centerpull brakes with a backing plate for bolt-on mounting, in limited quantities. Many customers have asked for this: Wouldn’t it be nice to get the superlight weight and superior performance of these brakes on an existing bike?

A backing plate connects the pivots with the fork crown, which makes it possible to bolt these brakes onto any bike with brake-mounting holes in the fork crown and in the rear seatstay bridge. You’d get much better performance than most other long-reach brakes, which often suffer from excessive flex and offer only poor braking performance.

For us, the problem was cost: A backing plate requires a new forging die, which is very expensive. We would have to sell hundreds of bolt-on brakes to amortize this cost. We could CNC-machine the plate, but then it would have to be much larger to offer the same strength, negating the light weight and elegance of the forged Compass brake arms. What to do?

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At this point, I was reminded of Preston Tucker, who introduced his revolutionary “Torpedo” in 1948 (above). Unable to get his new torque converter transmission ready in time for the car’s launch, Tucker’s engineers realized that transmissions from old Cords could be used in the new Tucker. So Tucker’s team scoured scrapyards to recover these transmissions, which were rebuilt with strengthened parts and installed in the first Tuckers.

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I realized that the backing plates we needed also were lying around in parts boxes and junk bins: They had come off old Mafac Raids when builders used those brakes with brazed-on pivots. In fact, I had a set myself, left over from building my René Herse way back before Compass brakes were available. The backing plates don’t wear out – any play in the bushings comes from wear of the aluminum arms, not the steel pivots – so the old Mafac backing plates remain as good as new. We found a number of these, and had them refurbished and polished by our friends at Norther Cycles in Portland.

Now we are offering the Compass centerpull brakes with backing plates. The brakes are sold individually, with all the hardware needed for bolt-on mounting. If your frame has recessed brake holes, you can either use the supplied bolt and nut, or you can modify the bolts and use recessed nuts.

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Of course, the backing plates add some weight and flex, so they’re not the ultimate solution. If you are thinking about repainting your frame anyhow, just have a framebuilder add the braze-ons and use our standard centerpulls. That is what Steve Frey did on his “hot-rodded” Trek (above), which we featured in the Winter 2016 Bicycle Quarterly. Or add braze-ons to the fork (as well as rack-mounting eyelets) and use a bolt-on brake on the rear, where you don’t need that much braking power.

Quantities of the bolt-on centerpulls are limited by our supply of backing plates. And if you have a spare set of Mafac Raid backing plates (distance between pivots: 75 mm), or a spare set of bolts and hardware for bolting the backing plates onto the frame/fork (all models), please get in touch. Like Preston Tucker, we are paying good money for what otherwise would be useless parts.

Click here for more information about Compass centerpull brakes.

Posted in Brakes | 18 Comments

Riding with the Compass Crew

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Most of the staff at Compass Cycles consists of avid cyclists. In fact, we knew each other on the bike long before we started working together. Occasionally, Compass has a “company ride”.

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Our last ride went north. It was one of those perfect mid-winter rides. The snow-covered mountains were crisp and clear, full of promise for our summer adventures. Conversation alternated with working together in a paceline. We enjoyed the steep, curving descent into the Snoqualmie Valley (above).

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While we enjoyed pastries in Snohomish, our trusty steeds were parked outside. Left to right: Theo’s MAP randonneur bike, my Firefly fat-tire racer, and Gabe’s Pelican city bike. Very different machines, and yet similar in many ways: All are designed for performance, with low-trail geometries, Compass tires and René Herse cranks.

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We rode through the bucolic Snoqualmie Valley, enjoyed a second food stop at our favorite taco truck in Monroe, and then headed home on beautiful backroads (above). It was nice to get out of the city, and we still made it back at the office for the 3:30 Fedex pickup… Now we just wish we could find time for a Compass ride every week!

Posted in Rides | 13 Comments

When to Use Knobby Tires

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Compass has long championed the use of “road” tires on gravel. More and more gravel racers agree: When gravel is sliding on gravel, knobbies are of little use.

So then why does Compass offer a knobby tire, the Steilacoom 700C x 38 mm? Knobs are useful in mud. They dig into the surface, and since the mud is viscous (gooey), it provides something for the knobs to push against. That is why cyclocross bikes use knobby tires.

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It’s important is to space the knobs widely, so the mud is ejected as the tire rotates. Otherwise, the tire just clogs up, and soon you are riding on slick tires again, except that their tread is made of mud instead of rubber. What you want is a muddy bike, but clean tires (above) – the tires pick up mud only briefly before it is flung off.

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Snow is a different story again. Depending on your speed, it behaves differently. At high speeds, you glide through the snow almost as if you were skiing, and tread patterns make little difference. At low speeds, you compact the snow and create the surface on which you ride. Knobs dig into that surface and give you extra grip. Even a herringbone tread works OK. Slick tires or longitudinal ribs act like the runners of a sled – they just slide and offer very little traction.

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What about ice? Ice is too hard for rubber tread to dig into. You need metal studs that bore into the ice to find traction. Sometimes, snow compacts to ice (above). I prefer to walk rather than risk a fall when I see ice on the road. (Unfortunately, I don’t know of a good method to see “black ice” before it’s too late.)

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Back to mud, where knobbies make the biggest difference: Designing a good mud tire isn’t hard – space your knobs widely, and the tire will self-clean as it rotates. The downside is that it’ll be buzzy and slow on pavement. I love the FMB Super Mud tires (above) on my old ‘cross bike (our Steilacooms don’t fit!), but their secret isn’t in the tread pattern – the extra-supple casing makes them wonderfully fast and contributes to their great traction. The tread is incredibly buzzy on pavement. It’s good that most ‘cross courses include no more than a few meters on pavement.

The knob shape itself makes little difference. “It’s all about ‘design'” a Panaracer engineer confided.

dual_purpose_tireDesigning a knobby tire that rolls OK on pavement is not too hard, either. Space your knobs closely, and the tire will roll fine. But when it gets muddy, the tire will clog up, depriving you of the advantages of a knobby tire. You get only the disadvantages of knobbies, without many of the benefits.

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Designing a tire that rolls well on pavement and grips well in mud is much harder. If you also want the tire to corner well without knobs folding over and suddenly losing traction, it seems almost impossible. And yet… with the engineers at Panaracer, we spent a lot of time analyzing and testing knob designs during the development of our Compass Steilacoom 700C x 38 mm knobbies. We found a few things that can greatly improve a knobby’s performance on pavement, without detracting from its ability in mud. More about that in a future post…

Click here for more information about Compass tires.

Photo credit: Wade Schultz (bottom photo)

Posted in Testing and Tech, Tires | 33 Comments