Optimizing Tire Tread


Most tire manufacturers agree that supple sidewalls and a thin tread make a tire fast, but the role of the tread pattern remains poorly understood. Most modern tires have either a completely smooth tread (slicks) or a coarse tread pattern similar to car tires. Many high-performance tires are smooth with just a few large sipes. None of these tread patterns are optimized.

Car tires have tread mostly to prevent hydroplaning. With their wide, square profile, a layer of water can form between tire and road surface. The tread pattern forms channels so the water can be pushed out of the tire/road interface.

Bicycle tires do not hydroplane. Their contact patch is too small and too round for that. This means that car-inspired tread patterns are not necessary on bicycle tires. Does this mean that no tread pattern at all – a slick tire – is best? Any tread pattern reduces the amount of rubber on the road surface… In the lab, it does work that way: Slick tires grip best on smooth steel drums.

Real roads are not as smooth as steel drums. An optimized tire tread interlocks with the irregularities of the road surface to provide more grip than the pure friction between asphalt and rubber. This is especially noticeable in wet conditions, when the coefficient of friction is reduced by half, yet you can corner with about 70-80% of the speed you use on dry roads. (Unless the road surface is greasy…)

The ideal tire tread has as many interlocking points with the road surface as possible. The “file tread” found on many classic racing tires does this. The ribs are angled so they don’t deflect under the loads of cornering or braking.

Why do race cars use slick tires, and not a file tread? The reason is simple: It would be abraded the first time the car accelerates. However, bicycle tires don’t wear significantly on their shoulders – the part that touches the ground when you corner hard – so we can use a tread pattern that is optimized for grip without worrying about wear.

Each Compass tires has three distinct tread patterns, each designed for a specific purpose.

  • Center: Fine ribs serve as wear indicators. When the lines disappear, the tire is about half-worn. (The tread of our narrower tires is not wide enough for ribs, so small dots are used instead.)
  • Shoulders: When the bike leans over as you corner, the tire rolls on it shoulders. A chevron or “fine file” tread pattern optimized grip.
  • Edges: This part never touches the road (unless you crash). They serve only to protect the casing from punctures, so they don’t need any tread.


Supple casings make tires faster, but a supple casing is of little use when it’s covered by thick tread rubber. The fastest tire would have just a minimal layer of tread rubber, and many “event” tires are made that way. Unfortunately, that means that they don’t have much rubber to wear down until they are too thin to use. At Compass Bicycles, we call these tires “pre-worn”.

Compass tires have a slightly thicker tread in the center. A little more material there doubles or even triples the life of your tire, while adding minimal weight and resistance. (On our widest 650B x 42 mm tire, the added tread weighs less than 50 grams.) Once you have ridden the tires for a few thousand miles, they’ll be as light as the “event tires”.

On the shoulders and edges, the tread does not wear. So we made it much thinner to keep the tire supple and reduce its weight. The tread extends far enough down the sidewall that the casing is protect when seen from above. Extending the tread further adds little protection, but makes the tire less supple and thus less comfortable and slower.


Another important factor is the tread rubber. This is an area where incredible progress has been made in recent decades. In the past, you could either have good grip or good durability. I used to ride Michelin’s Hi-Lite tires, which gripped well, but rarely lasted even 1000 miles (1600 km).

Compass tires use Panaracer’s best tread rubber, which is amazing. Our tires are among the grippiest you can find, yet I just got an e-mail from a 230-pound rider who got 3786 miles (6093 km) out of a set of our 26 mm-wide Cayuse Pass tires. The wider tires spread the wear over more rubber, so they last significantly longer. (Don’t try to set wear records, but replace your tires once they get thin. The risk of flats, or worse, blowouts, is not worth getting an extra few hundred miles out of a worn tire.)

Tread color is another important consideration. Modern colored treads no longer are the “death traps” they used to be, but especially in wet conditions, the grip of tires with colored treads – including the Grand Bois Hetres we sell – is not quite as good as that of black treads. That is why we offer only black tread.

Click here for more information about Compass tires.

Update 9/25/14: Roadbikerider.com just published a review of the Compass tires. Click here to read it.



Posted in Tires, Uncategorized | 54 Comments

Cycling Books That Have Inspired Me


I recently thought about my favorite books. There are many, and they span a wide range of topics, from Saint Exupéry’s The Little Prince to The Art of the Motorcycle. Here are six of my favorite cycling books, in no particular order. This is not a “recommended reading” list; it’s a personal list of books that have inspired me. In any case, many of these books are difficult to find or written in French or Japanese.


From Repack to Rwanda was a gift from Jacquie Phelan. It’s a catalogue for an exhibit by the SFO Museum at the San Francisco International Airport. From Repack to Rwanda chronicles the development of the mountain bike and shows great studio photos of dozens of pioneering machines. It starts with the Schwinn Klunkers, then the first Breezers and Ritcheys, Cunninghams, the 1981 Specialized Stumpjumper, as well as wonderful machines like the Ibis Bow-Tie with its pivot-less Sweet Spot suspension. It’s by far the best book on the subject, and the fact that it was given to me by a mountain bike pioneer makes it all the more special. Thank you, Jacquie!


Bernard Déon’s Paris-Brest Et Retour really turned me on to the history of French randonneurs and their wonderful machines. I met Déon at the finish of my first PBP in 1999 and ordered the book shortly thereafter. The book’s reports from the early races and later randonneur events were fascinating, but I was equally impressed by the bikes. I realized that if riders like Roger Baumann had completed PBP in 50 hours through rain and wind in 1956 on René Herses, then the bikes must have been very good, and not mere show-pieces, as many assumed at the time.

I became determined to learn more about this event and these bikes. In a big way, this book was at the start of Bicycle Quarterly, Compass Bicycles and even my own randonneuring. Unfortunately, this book was printed only in a small run, so it’s almost impossible to find. And Déon’s style requires greater-than-average proficiency in French.


The Japanese have been excited about French cyclotouring bikes much longer than I have even been alive. They have published many wonderful books on the subject. My favorite is this gorgeous tome about Toei, the famous builders from Tokyo. Unfortunately, I cannot read the Japanese text, but the photos alone make this a favorite. It shows in great detail how Toei’s style developed over the years, until it reached close to perfection in recent decades. This book still is in print, and we may be able to import it and offer it in the Bicycle Quarterly Bookstore.


Simon Burney’s Cyclo-Cross is a great how-to guide for aspiring ‘cross racers. It was strongly recommended by a friend in the 1990s, who was the Master’s Women national champion. I tried to absorb every line of it, and if I had any success in cyclocross, it was thanks to Burney’s clear advice. Mine is the first edition, with Graham Watson’s action shots that add to the appeal of this excellent little book.

My copy of Paul Fournel’s Need for the Bike doesn’t have a jacket, so there is no photo here. Originally given to me by its English translator (and Bicycle Quarterly reader) Allan Stoekl, I greatly enjoyed this little book. Fournel is a philosopher, who writes about why we ride. On every page, I smiled and nodded my head. For example, Fournel writes about a spring on a descent. He’s never seen it, but he knows it’s there because he feels the cool air as he rides past it. This sustains him for miles afterward.

I lent my copy to a friend who was very ill and never got it back. I finally managed to track down a hardcover copy from a library sale. Need for the Bike is the only book on this list that is currently available in the U.S. (paperback).


Routes, Risques, Rencontres translates to “Roads, Risks, Encounters”. Its author, Lily Serguéiew, was an artist who decided to ride from Paris to Saigon in 1938, on her aluminum Caminargent bike. She took her time, learning the language in every country she traversed, drawing, and meeting the local people. Her adventures are both breathtaking and sweet.

In the former category is her trip through the desert of Turkey, despite being denied a visa, which led to her being chased by the police for several days. The sweet moments included being invited to participate in a wedding in Greece. Her trip ended prematurely when World War II started while she was in Aleppo (Syria). She returned to France, where her book was published in 1943. If you read French – the language is less complex than in Déon’s book above – I recommend trying to find a copy.


The final book here is Hilary Stone’s Ease with Elegance. This story of Thanet Cycles, the makers of the famous Silverlight machines, lives up to its name. Different from so much “cycling history”, it’s a well-researched yet engaging read. The “guv’nor” (Les Cassell) must have been quite a character! It’s a truly charming book that had me dream of a Thanet for years. I got my book directly from the author, Hilary Stone, and I believe he has some copies left.

What are your favorite cycling books?

Posted in books | 25 Comments

A great time was had by all!


Last weekend was the first Bicycle Quarterly “Un-Meeting”. The weather was perfect, about 25-30 riders showed up, and everybody had a great time. Aside from handing out copies of route maps, I was just another participant and was able to enjoy the meeting like everybody else. It was nice to see familiar faces and meet new people.


Most riders were from Washington State, but two had come from much further. George Retseck (on the left) came all the way from Pennsylvania. Many know George as the illustrator of the old Bridgestone catalogues. He has been doing some wonderful work for Bicycle Quarterly, too. Another rider came all the way from New York City!


The riding was wonderful. Instead of splitting up into groups, almost all of us decided to do the “intermediate” ride. We re-grouped a few times, and it seems that everybody enjoyed the riding and the company.


We had lunch at the historic lodge in Mount Rainier National Park, and then most of us climbed to Paradise.


That night, we congregated around a campfire. You can barely see the stars in the photo above. In real life, they were truly amazing. Sunday morning greeted us with more beautiful weather, and we set off for home.

We hope you are inspired to take up the idea and organize your own “Un-Meeting”. All it takes is figure out a few rides, make route sheets, set a date, and show up!

Photo credit: Andrew Squirrel (campfire).

Posted in Rides | 5 Comments

SKF Bottom Brackets after 5 Years


It’s been five years since Compass Bicycles started selling SKF bottom brackets, and three years since we became the world’s exclusive distributor. At that point, we extended the warranty to 10 years, since we had great confidence in the quality of these bottom brackets. They have patented labyrinth seals, and their oversize bearings run directly on the spindle and shell. There was no reason to doubt the claim of the SKF engineers: These bottom brackets should last 100,000 km of rainy riding. Since most of us don’t ride in the rain all the time, they should last even longer in real life.


Now the first bottom brackets that we’ve installed are half-way through their minimum expected lifespan. I am happy to report that they have proven as reliable as we had hoped. Both on our own bikes and on most customers’ machines, they simply do their job. Mark and I installed ours four years ago, and then forgot about them. They still spin as smoothly as they did on the day we installed them.

Out of several thousand bottom brackets sold, we’ve had fewer than a dozen warranty returns. Some were due to grit getting trapped in the outer seals. The seals did their job, and the contamination never reached the bearings, but the grit could be felt when turning the bottom bracket spindles by hand. While this isn’t a defect, we replaced the units for new ones.


There were three fluke failures, with the most bizarre coming from the rider who overhauled his bike, reassembled it, and the next morning, he found both cranks lying on the ground next to the bike. The spindle had broken on both sides! Since this was an ISIS “Mountain” bottom bracket, we replaced it with the “Freeride” version, which has a smaller hole in the spindle, and thus much stronger spindle. Considering the huge loads a bottom bracket undergoes, this rate of warranty returns is extremely small. It confirms that the confidence we placed in these bottom brackets has not been misplaced. We look forward to the next five years of selling and riding with these bottom brackets.

SKF bottom brackets are available with JIS and ISO tapers, as well as for ISIS cranks. They come in BSC, Italian and French threading. Click here for more information.


Posted in Bottom brackets | 35 Comments

Packwood “Un-Meeting” Route Sheets


Next weekend is the Bicycle Quarterly “Un-Meeting” in Packwood. The weather forecast is great: warm during the days, a little cooler at night, sunshine. Bring sunscreen! Here are a few things about logistics:

Getting there: Here is a route from the nearest train station in Centralia to Packwood.

For those riding from Seattle, there are several routes, either via the Green River Trail, Enumclaw and Cayuse Pass, or via Sumner, Eatonville and the Nisqually valley. We’ll probably take the latter, so we may see you out there on Friday.


Meeting is at 9 a.m. on Saturday, Sept. 13,  at the Packwood library (above, right in the center of town, across the street from the Hotel Packwood and the Packwood Campground).


Here are three rides in the area that we plan to do. Please be aware that the terrain is very mountainous and challenging. Don’t overestimate your capabilities! There is no cell phone service, and nobody to pick you up if you cannot make it.

  1. Packwood, Skate Creek Road, Longmire, Paradise (Mt. Rainier National Park). A scenic road, all paved except a short stretch of smooth gravel to get into the park (through the backdoor). 52 km/ 33 miles round-trip. Extension to Paradise (4500+ ft climb) possible, for a total of 90 km/60 miles round-trip. Lunch available at Longmire and Paradise lodges (sit-down restaurant). Return the way you came (preferred), or by descending to Box Canyon, Ohanapecosh, Packwood (last 8 miles on busy highway). Click here for map, and here for route sheet.
  2. Packwood, High Rock, Longmire, Paradise (Mt. Rainier Natl. Park). Same as 1, but going over the top of the ridge at High Rock, rather than in the valley at Skate Creek. Adds beautiful views, and gravel. 76 km/48 miles round-trip. Extension to Paradise (4500+ ft climb) possible, for a total of 117 km/73 miles round-trip. Lunch available at Longmire and Paradise lodges (sit-down restaurant). Return the way you came (preferred), or by descending to Box Canyon, Ohanapecosh, Packwood (last 8 miles on busy highway). Click here for map, and here for route sheet.
  3. Packwood, Walupt Lake, Babyshoe Pass, (Trout Lake), Randle. A long gravel climb, a beautiful mountain lake, Babyshoe Pass. Plenty of gravel. Possibility to turn around at Walupt Lake (73 km/45 miles round-trip). 145 km/90 miles with no services for most of the ride. Extension to the remote Trout Lake with its diner famous for blackberry shakes offers services, but full distance is 223 km/140 miles. Click here for map, and here for route sheet.

Please print the route sheets for the rides you plan to do, since we’ll only have a few at the start.

On Saturday night, there will be a campfire at the Packwood Campground. On Sunday, we’ll ride back to Seattle.

About the Bicycle Quarterly “Un-Meeting”: The “un-meeting” isn’t an organized event. There is no entry fee, no services will be provided, there are no rules, and there is no insurance or liability of any kind. The goal is to meet like-minded cyclists and to have a good time. We hope to see you there!

Posted in Rides | 10 Comments

Scouting the Bicycle Quarterly Un-Meeting


On Labor Day, I scouted the routes and logistics for the Bicycle Quarterly “Un-Meeting”, which will be held (or “un-held”) in Packwood on September 13. After a few rainy days, it was a gorgeous sunny morning. With my family, we had been hiking in the area, so I started in Greenwater with the climb up Cayuse Pass. It was sunny and warm, but a few clouds obscured the top of Mount Rainier.


The sign on top of Cayuse Pass became a casualty of avalanches or snowplows a few winters ago, so now the “proof of passing” is the road sign at the top.


I added the bonus climb to Chinook Pass – an out-and-back that was well worth the effort for the magnificent views at the top.


I wasn’t the only one enjoying the mountains. This VW Beetle-based Bugatti kit car roared down the mountain, making me a little envious of the fun its crew had. Except I had as much fun as we both roared down the long descent of Cayuse Pass. They stayed behind me for a long time, until I waved them past to get a better view.


The last miles to Packwood always are into a headwind, but they passed quickly. Here is the library, right in the middle of town. We’ll start our rides here at 9 a.m. The Hotel Packwood is across the street…


… and the campground is next door. The Bicycle Quarterly crew will stay at the campground, and we’ll have a campfire on Saturday night.


Packwood is nice, but its true attractions are the roads that radiate into the mountains. I went up Skate Creek Road, a perennial favorite that winds its way up a narrow valley.


Skate Creek Road is hard to surpass, but this small forest road is even better. It climbs and climbs at a moderate gradient, with views of the mountains from time to time.


I had no trouble finding the turn-off to Forest Road 84 – a good thing, since it’s part of one of our rides. Despite the sign that the road isn’t recommended for cars, the gravel was very smooth – more like hard-packed dirt than normal gravel.


For the first time, I came through here on a clear day (once I had been through here in a snowstorm, and twice at night). The view was as spectacular as I had imagined it, but I was disappointed that Mt. Rainier was still surrounded by clouds, with only the very top peeking out.


Then my attention was occupied by the descent. It’s ultra-fast if you let the bike roll, and great fun.


I re-joined Skate Creek Road in the Nisqually valley, and got another glimpse of Rainier’s summit – well, almost.


I entered the National Park through the back door. (I have an annual pass, and this route is 10 miles shorter and free of traffic.)


I always enjoy the old suspension bridge at Longmire, but even more today…


…since this was my big dinner stop. I had to wait 30 minutes for the restaurant to open, but it was well worth the wait. (I wrote some postcards in the mean time.)


The early dinner was followed by the long climb up to Paradise. While it’s a significant climb, it’s not very steep, and the gradient varies, so whenever you start to get tired, it relents, and you get a little rest. I stopped on the bridge over the Nisqually River and looked at the glacier (barely visible, covered with rocks, up the valley). The clouds above were a bit disconcerting – I had to hurry to get over the top before it got dark and really cold.


Looking down gave me a vertiginous view of the river… better to get going before I got dizzy.


The Paradise Lodge was as beautiful as ever, with a piano player and guests lounging after a day exploring the mountain. I resisted the temptation to stay for dessert, since the sun was setting outside.


And what a sunset it was, with the mountains glowing in orange and pink.


Just to tease me, there was another “almost” view of the mountain as I passed Reflection Lakes. It was twilight here, and I encountered a young black bear leaping onto the road about 40 feet ahead of me. I braked hard, and we both were equally surprised as we faced each other at close range. By the time I got my camera, the bear had disappeared into the undergrowth.

The super-fast descent to Box Canyon had me shiver a bit on my bike, but the climb up Backbone Ridge warmed me up alright. It was dark now…


… and as I looked back, I finally got a view of the summit free of clouds. I’d been chasing this view all day over four mountain passes, and here, in the fading light, the mountain finally revealed itself.


One mountain pass remained, but even the climb up the long side of Cayuse Pass wasn’t as challenging as it had been when I last rode it after 500 km during the Volcano-High Pass Super Randonnée.

It was 10 p.m. when I crested the pass. The ride back to Seattle was another 100 miles, but it passed quicker than I thought. In the still night, my bike seemed to fly, and even a few light rain showers didn’t dampen my spirits. Leaving Enumclaw on small roads, not a single car passed me for the next two hours, nor did I meet anybody during the next hour on the Green River Trail. I arrived home at 4 a.m., a little later than planned. It was a lovely ride, and I honestly can say that I enjoyed every minute of the 19 hours I was on the road. I just hope that the weather will be similarly nice next Saturday, except with fewer clouds over Mount Rainier!

About the Bicycle Quarterly “Un-Meeting”: The “un-meeting” isn’t an organized event. There is no entry fee, no services will be provided, there are no rules, and there is no insurance or liability of any kind. All that happens is that the Bicycle Quarterly crew will be doing a few rides starting at the Packwood Library at 9 a.m. on Saturday, September 13. Distances will range from 40 to 80 miles, and anybody is welcome to join us. In the evening, there will be a campfire. The goal is to meet like-minded cyclists and to have a good time. On Sunday, we’ll ride back to Seattle. We’ll post the route sheets in a few days, so you can print them out and bring them along. We hope to see you there!

Posted in Rides | 12 Comments

Autumn 2014 Bicycle Quarterly


The Autumn 2014 issue of Bicycle Quarterly is at the printer. It will be mailed soon. We are excited to share a variety of topics with our readers.


The Oregon Outback was an exciting gravel event, and we bring you right into the action with two features. One brings you the atmosphere of the ride, while the other examines what makes a perfect gravel bike.


Speaking of bikes, we test the Ritchey Swiss Cross. Can a cyclocross bike keep up with a good road bike on smooth pavement, yet also tackle gravel roads off the beaten path?


The Toussaint Velo Routier is an affordable 650B frame. We take it on a ride to find out how it performs.


Junzo Kawai, long-time chairman of the board of Suntour, died recently. We look at his life and how he led Suntour toward remarkable innovations that we continue to use today.


We visited Tokyo and here report on the cycling culture of this amazing metropolis. Among many surprises, we found double-decker bike racks and juvenile wanna-be outlaws on bicycles with neon lights and batman wings.


Tokyo also is home to Honjo, makers of the world’s most beautiful fenders. We take you on a tour and show you how metal fenders are made.


Fenders are great to keep you and your bike dry and clean, but they also can cause accidents. We look at how to make your fender-equipped bike as safe as possible, so you don’t have to worry about your fender folding up and throwing you over the bars.


Product tests in this issue include SRAM’s revolutionary 1×11 drivetrain (above) and a minipump with a neat pressure gauge (below).


Click here for more information about Bicycle Quarterly or to subscribe.

Posted in Bicycle Quarterly Back Issues | 11 Comments