Cyclotourist Magazine: The History of Randonneuring

Yesterday’s mail brought a nice surprise: the May issue of the Japanese magazine Cyclotourist, with an article I wrote about the history of randonneuring and of randonneur bicycles in France.

Unfortunately, I don’t read Japanese, but from what I can tell, they did a very nice job with the 6-page article. My article provides an overview of randonneuring and the many events associated with the sport, like Paris-Brest-Paris and the Polymultipliée de Chanteloup hillclimb race.

I always enjoy writing for other publications, as it provides an opportunity to introduce our research to new audiences. Bicycle Quarterly has many readers in Japan, but this article, which was translated into Japanese, overcomes the language barrier and provides a historical background for the bicycles that the Japanese admire so much.

Handlebar Bags: Which Size for Your Bike?

What size handlebar bag is best for you and your bike? Basically, the bag should fill the space between the front rack and the stem. To optimize the bike’s handling, the bag should be as low as possible, and well-supported on a rack just above the front wheel/fender. At the top, the bag attaches to the handlebars or stem to prevent the bag from swaying. When the bag’s top flap is level with the top of the handlebars, the bag contents are easily accessible while riding.

More space between the wheel and stem means that taller riders use bigger bags. Unfair? Maybe, but a taller rider’s clothes also take up more space. What if you don’t need that much luggage space? Then think of the bag as a fairing; it makes sense to size it so that the bag shields your chest cavity when you are in the drops or the aero tuck.

On some rides, my handlebar bag contains only a spare tube, tire levers and some money. I could just wrap those in a piece of cloth and strap them to the rack, but I don’t bother with that, just like I don’t take off the second bottle cage when I go for a ride that requires only a single waterbottle. In my car, I also don’t fill up the trunk on every trip. I think of the bag as an integral part of the bike.

If you look at the slightly bulging flap of my bag shown in the photo above, you’ll see that I often fill it to capacity and beyond. Sometimes it’s a day that starts chilly and warms up, and I need a place to stuff my extra clothes. Other days, I pass by the Farmers’ Market on the way home from a ride, and I am glad to have a place to put some vegetables and flowers. The photo above was taken after last year’s Paris-Brest-Paris ride, during a three-day trip across France to visit friends. The large bag meant that I didn’t need to bring the bolt-on rack flanges and panniers.

The largest Gilles Berthoud bag has 42% more capacity in the main compartment than the smallest bag shown above, yet it weighs only 11% more (not counting the superfluous stiffener). The weight of the bag comes from the leather reinforcements, pockets, straps and buckles, while the fabric is very lightweight. The larger bags just have a little extra fabric. The weight difference between the largest and smallest bags is 61 g, which is about the same as an empty bottle cage. As mentioned above, I don’t worry about riding with an empty bottle cage on my bike, either.

Gilles Berthoud makes their classic handlebar bags in three sizes. This range fits most bikes. If you need something significantly different, Phil Woosley of Loyal Designs, Guu Watanabe in Japan and others can make custom bags to your requirements. Click here for more information on the Gilles Berthoud bags, including dimensions and weights.

Mounting Tires on Rims with Deep Wells

Sometimes we get a call or an e-mail from a frustrated customer: “I have a brand-new set of your tires, and both wobble when I mount them on my rims.” In most cases, it is not the tires’ fault. Usually the problem  stems from the difficulty of mounting tires on poorly designed rims. However, there are some tricks for mounting tires on these rims.

Above, you see a correctly mounted tire. Most tires made today have a line molded into the sidewall (arrows). This line must be visible all around the tire, and parallel to the rim edge. The line not only helps seat the tire, it also serves as a visual indicator that the tire is concentric with the rim. (Usually, the line is a little higher above the rim, but always parallel to the rim edge.)

Above are three 700C rims, which all have the same outer diameter. However, the cross sections show that they are very different on the inside. Rim 1 is a proven design. Rim 2 has a shallower well (the place where the tire mounts). Rim 3 has a very deep well. Tires seat differently on each of these rims.

When you mount a tire, the tire beads need to go over the rim’s hook (above; the foam is used to hold the tire in shape). Tire beads are what holds the tire on the rim. They don’t stretch much – otherwise, the tire would just blow off the rim when you inflate it. The well of the rim has a curved bed. When you mount the tire, the tire beads drop into the center of the rim’s well bed. This provides enough slack to get the last bit of tire bead over the rim’s hook on the opposite side. As you inflate the tire, the beads slide up the rim’s curved well bed until they seat tightly underneath the rim’s hooks.

The photo above shows Rim 1. The tire’s beads fit perfectly onto the well bed and underneath the hook. The tire will seat concentrically by itself as you inflate it. The bead seat diameter is 622 mm, as industry standards specify (ETRTO). This is how rims should work.

Rim 2 has a shallower well. The bead seat diameter is 624 mm, which makes the well bed higher than the standard 622mm. To seat correctly, the tire has to stretch by 2 mm in diameter. This translates into 6.5 mm (1/4″) along the tire’s inner circumference, which is a lot of stretch for a tire bead. Often, the beads don’t stretch enough, and don’t quite reach the rim walls (arrow). Then the tire will wobble on the rim. Putting talc (baby powder) on the tire bead may help it slide into position. A very thin and slippery rim tape also can be helpful.

The high well bed also makes the tire difficult to remove: It is difficult to insert a tire lever underneath the tire bead, because it is stretched so tight onto the rim.

Rim 3 has a very deep well. The tire is not supported by the well bed at all (arrows). The tire has to float. When you inflate this tire, it cannot just slide into position on the well bed. You will have to manipulate the tire until it is seated correctly.

Unfortunately, two common rims for wider tires, the Velocity Synergy and the Grand Bois, have overly deep wells. This makes mounting tires difficult. The sole advantage is that the tires come off the rim easily.

On their 650B rims, Synergy tried to “fix” the problem of poorly seating tires by increasing the overall rim diameter. In my experience, this has made things worse, because now the hook is in the wrong place. There is nothing to locate the tire: The well still is too deep, so the tire cannot sit on the well bed. And the hook is too high, so the tire cannot sit underneath the hook.

If you have rims with wells that are too deep on your bike, there are some tricks for mounting tires on them. There even is a “fix” that can overcome the problem of the overly deep wells to a large degree.

On all rims, even well-designed ones, tires often don’t seat well at the valve. The tube is reinforced here, making it stiffer, and it sometimes gets caught under the tire bead. Above, you see how the molded-in line moves away from the rim at the valve. (Often, this is more pronounced.) Not only will this cause the tire to wobble, but if the tube is trapped under the beat, it can chafe until you get a flat tire.

With the tube barely inflated (~5 psi), push the valve stem inward as far as you can. This usually frees the part of the inner tube that is trapped.

Harder to fix is the problem shown above: The line that is molded into the tire sidewall disappears into the rim (arrow). This often happens on rims where the wells are too deep, such as the Synergy Velocity shown here. (The Grand Bois rims we sell unfortunately are not much better.) It also can happen if the well is too shallow, and the tire bead does not contact the rim sidewall.

Push the tire to get it into the right place. Inflate it to about 15 psi, and use both hands to push it away from you, until the molded line appears. Go around the tire on both sides until the molded line is visible everywhere and parallel to the rim edge. This takes patience. It can be frustrating, and it’s the last thing you want to do when you have a flat on the road and all your friends are waiting for you to get back on the road.

To address the problem of the overly deep wells, you can add two layers of rim tape (or handlebar tape, which is the correct width for 23 mm-wide rims). This raises the bottom of the well. Now the tire should seat correctly without as much manipulation.

Do not ride a poorly seated tire! The tire could come off the rim and cause a crash.

Of course, it would be nice to have correctly designed rims, where the tires seat automatically as you inflate the tubes. We are working on this! In the mean time, Compass Bicycles is including extra rim tape with every set of Grand Bois rims we sell, so you can correct the problem of the overly deep wells.

Daniel Rebour

Even though Daniel Rebour retired almost 40 years ago, his drawings remain recognizable to many cyclists today. Rebour’s drawings distilled the essence of components and bicycles better than photographs ever can. He managed to make even the most mundane bicycle appealing, and his drawings greatly added to the allure of the wonderful machines made by the great constructeurs.

Rebour visited bike shows all over Europe and even in North America when he worked for the trade magazine Le Cycle. Over the years, he chronicled technological progress. Historians today turn to his articles and drawings to figure out, for example, the history of Campagnolo’s first derailleurs, the Gran Sport, through its convoluted gestation. Rebour was there, and recorded what he saw in his drawings.

Rebour was influenced by the French constructeurs’ emphasis on the “line of the bike,” and in return, his drawings influenced how the French saw bikes. Rebour did not dwell on intricate lug cutouts, but focused on the proportions and outline of the bike. His drawings look especially exceptional when they depict bicycles with good fender lines and nicely proportioned frames.

Rebour’s work reflects a true love of cycling and of bicycles. Bicycle Quarterly photographer Jean-Pierre Pradères visited Simone Rebour many years ago. He interviewed Simone and obtained access to Rebour’s archives. In Bicycle Quarterly Vol. 2, No. 4, Jean-Pierre related their fascinating story.

Daniel and Simone Rebour were active cyclotourists. For their honeymoon, the Rebours rode a René Herse tandem to a new mixed-tandem record in the 1948 Paris-Brest-Paris (above). They went touring by bike, but also entered competitions like the Poly de Chanteloup and the Brevet Randonneur des Vosges. In 1949, Simone Rebour set the women’s record for the 200 km brevet, with a time of 6:57 hours – faster than most randonneurs ride today.

Daniel Rebour also wrote an introduction to cycling (above) where he explained what to look for in a bicycle. The book was reprinted in several editions for almost 30 years.  Rebour’s second love was motorcycling, and he published many articles and drawings in Moto Revue under the pseudonym “Paul Boyenval.” He also wrote an introduction to motorcycling that is similar to his book on cycling.

It is thanks to Rebour’s many drawings, often titled “Nouveautés au Salon du Cycle” (“New Products at the Paris Bike Show) that we can piece together the history of bicycle components, both from the large manufacturers and from the small constructeurs. Above is part of an article from the 1960 Salon du Cycle, which saw the introduction of the Mafac “Kathy” cantilevers and the “Tiger” centerpulls.

Imagine this larger-than-life figure, working on his detailed drawings in his country house in Normandy, and then, at the end of a full day, getting on his Herse to go for a ride… what a way of life!

The full story of Daniel Rebour, with many photos and drawings, was published in Bicycle Quarterly Vol. 2, No. 4.

If it so good, why don’t the racers use it?

A common objection to some of Bicycle Quarterly’s findings is: “If xyz is so good, why don’t the racers use it?” Whether it’s wide tires at lower pressures or front-end geometries, some of what we find to work best is not currently used by professional racers. Don’t professional teams do a lot of testing and development of their equipment? Isn’t it safe to assume that their equipment is optimized for the job at hand? I believe the answer is: “Not always.”

No professional racer used aerobars before Greg LeMond famously won the 1989 Tour de France with them (above). Earlier in 1989, I heard people say: “If aerobars offer such an advantage in time trials, why don’t the pros use them?” After all, Francesco Moser’s scientific team just had done a huge amount of research on bicycle aerodynamics to set a new hour record. Their research had determined the ultimate aerodynamic bicycle (shown on the cover below). Professional racers were using similar machines for their time trials.

On July 23, 1989, Greg LeMond was desperate: Going into the final stage of the Tour, he was in second place. LeMond was 50 seconds behind Laurent Fignon, and victory seemed just barely out of reach. LeMond had nothing to lose and everything to gain, so he had his mechanic install aerobars on his time trial bike. The more aerodynamic position gave him the advantage he needed to secure victory by 8 seconds.

The “state-of-the-art” time trial bike had become outdated from one day to the next. People realized that you had to improve the aerodynamics of the rider, not the bicycle, for optimum speed. All the research that went into Moser’s hour record turned out to be a blind alley. If Moser had slapped aerobars onto a standard track bike, he would have gone faster!

Imagine if LeMond had not been in second place going into the last stage of that Tour de France: Would racers still use “funny frames” and cowhorn bars in time trials today? I doubt it – eventually, scientific advances become accepted by the mainstream.

Take wider tires run at lower pressures: VeloNews reported that in this year’s Giro d’Italia, many teams used 25 mm-wide tubulars even on smooth roads. For more than 30 years, 21.5 mm tubulars were the standard tires in professional racing. Back then, pro racers used 25 mm tires only on the brutal cobblestones of Paris-Roubaix, “The Hell of the North” (below in the mid-1990s).

What caused the change to wider tires? Most important was the realization that lower pressures don’t make tires roll slower. This means that wider tires – which have to run at lower pressures – can be as fast or faster than narrower tires. Once this was established, at least partially through Bicycle Quarterly’s research, equipment makers could test wider tires in the wind tunnel and on the road. And they apparently found that wider tires perform better even on smooth roads. A mechanic explained: “You get more grip, more comfort; the guys like it.”

So when somebody says: “If xyz is so good, why don’t the racers use it?” perhaps the best response is: “Give them some time, and they probably will come around.”

Photo credit: ©John Pierce, Photosport International.

Dedication to Details

At Compass Bicycles, we tend to be a bit obsessive when it comes to our bicycles. “Good enough” usually is not good enough when we’re out on our bikes, and we apply the same exacting thoroughness to the components we sell. Take the Honjo fenders as an example:

When you buy Honjo fenders, you usually get a pre-packaged “kit” with bolts and hardware. Unfortunately, the eyebolts for connecting the stays to the fenders are 12 mm long, so they stick out a little over 4 mm beyond the nut into the inside of the fender (above right). Either you saw 4 mm off the eyebolts – be careful not to ruin the threads in the process! – or you risk having obstacles snag on the bolts that protrude 4 mm beyond their nuts.

Honjo actually makes 8 mm eyebolts (above left), but those are a special-order product and not available from their North American distributors. (Don’t ask me why!) To address this situation, we import the 8 mm bolts directly from Japan. When you buy your fenders from Compass Bicycles, we automatically replace the too-long eyebolts with the correct 8 mm bolts.

Getting the correct-length bolts is a bit of a hassle, and few people notice the difference, but that is beside the point. We don’t want our bikes to have protruding bolts inside the fenders, and neither should yours.

Rim Weight

At Compass Bicycles, we are not obsessive gram counters, but none of us want to carry extra weight on our bikes. A few grams here and there add up quickly to a couple of pounds, and that can make a difference not only in how the bike performs, but also how it feels when you ride it.

There are some components where you cannot save weight without undue compromises, and rims are a very good example. A well-designed clincher rim weighs about 450-500 g (650B) and 480-530 g (700C). To reduce this weight further, you only can remove material in four ways:

• Thinner sidewalls. Example: 1.3 mm instead of 1.6 mm. Savings: 30 g.* The rim sidewall abrades as you brake. You need at least 0.7 mm of sidewall thickness to keep the tire from exploding. With the thinner sidewalls, your rim can lose only 0.6 mm until it is worn out, instead of 0.9 mm. That means your rim will last only 2/3 as long.
• Narrower rim: Example: 20 mm instead of 23 mm. Savings: 24 g. On the down side, the rim no longer supports wide tires well.
• Thinner rim “floor” (the side facing the hub): Example: 0.9 mm instead of 1.0 mm. Savings: 11.4 g. Now there is less material to counter the stresses imparted by the spokes, and the rim is more likely to crack.
• Bottom of the well (the side facing the tire): Most rims already have the bare minimum here, so there are no further savings possible.
• Rim shape: A more triangular shape can save material over a traditional box section, but the brake tracks are much shallower. You will have to adjust your brake pads frequently as they wear, otherwise they will cut into the tire (with sidepull and centerpull brakes) or dive under the rim (with cantilevers).

None of these weight saving options are very appealing. In the end, a good rim has a certain weight, and there is little you can do about it.

If you really must have a lighter rim, just ride it, and it will get lighter every time you brake. Of the two rims shown above, one is 70 grams lighter. Both rims started out from the same extrusion (Mavic MA-2/MA-40). The rim on the left is brand-new. The rim on the right has been used for a few years. The abrasion of the brake pads has removed 0.7 mm from each sidewall. The rim has lost 70 g of weight, but it is close to the limit where it becomes unsafe to use.

Even if you are willing to compromise durability and tire support to save weight, all the potential savings add up to only 65 g per rim. If you use a disc-only rim, you save another 30-40 g, but the separate brake disc weighs more than you save on the rim. (And using “disc-only” rims with rim brakes is a bad idea for obvious reasons: the brake tracks are worn out from the onset.)

Here are a few better ideas to reduce the weight of your wheels:

• Folding tires: A Kevlar bead saves about 70 g per tire. Such a tire performs the same as one with a wire bead.
• Superlight Tubes. On a 650B x 42 mm tire, using a superlight tube saves about 45 g. The down side is that you’ll have to inflate your tires every couple of weeks, as the air leaks out of the thinner tube more quickly.

Together, the weight savings from lighter tires and tubes are more than you’ll ever get by using a “pre-worn” rim. Light weight components have their place, but they should not come with undue compromises.

* The circumference of a 650B rim is 183 cm, the sidewall is about 1 cm tall. The aluminum removed by making the sidewall 0.03 cm thinner is 183 x 1 x 0.03 = 5.49 cm3. There are two sidewalls, so you remove 9.98 cm3. Aluminum has a specific density of 2.7 g/cm3, so the savings are 9.98 x 2.7 = 29.6 g.