Tagesarchiv: 26. Januar 2015

Luft im Reifen? Im Prinzip egal.

via Jan Heine, Off the beaten path


Of all our research on tires, the most revolutionary finding is this: Tire pressure has almost no effect on a tire’s speed. We did not believe it at first, either, so we’ve tested it numerous times. It’s been confirmed numerous times, with different methodologies.

The real revolution is not how you use your pump… What has totally changed our riding are the wide, supple tires, which only work because of this new insight.


First, let’s look at the data. Here is one experiment: We ran three different 25 mm tires (a supple clincher, a supple tubular and a harsher-riding clincher) at pressures from 4.5 and 9 bar (65 and 130 psi). These tests were done on very smooth asphalt (above), a surface where high pressures should offer the greatest advantages.


There is no relationship between tire pressure and performance in the tested range. (Lower and higher pressures are unsafe to ride.) The graph above shows some variation in power output (lower is better), but there is no trend. The CX tubular rolls fastest at 5.5 bar, the CX clincher is a little faster at 6 bar, while the Rubino is fastest at 9 bar, but almost as fast at 6.5 bar.

Take-home message: Don’t stress about tire pressure!


This finding has revolutionized our understanding of tires. In the past, we all thought that higher tire pressures made tires roll faster. And that presented a problem for wide tires: A wider tire puts greater loads on the casing than a narrow one. To compensate, you have two choices:

  1. Beef up the casing, which makes the tire less supple and slower.
  2. Lower the pressure, which we thought made the tire slower.

No matter which route you took, then-available science predicted that your wider tire would be slower. It was a catch-22, and for the best performance, you stuck with narrow tires, where you could have a supple casing and high pressure at the same time.

But after realizing that tire pressure doesn’t matter for performance, we were able to explore new possibilities. If lowering the pressure does not make tires slower, you can make supple, wide tires. You run them at lower pressures, and you don’t give up any performance on smooth roads. On rough roads, you gain speed, because the tire (and you) bounce less. And on all roads, you are more comfortable. Instead of a catch-22, you have a win-win-win situation.


It’s this research that has led professional racers to adopt wider tires. They are up to 25 mm now. (Wider ones won’t fit on their bikes!) For the rest of us, there is no reason not to go wider. I now ride 42 mm tires at 3 bar (43 psi), knowing that they roll as fast as a 25 mm tire at 6 bar (85 psi) – or 9 bar (130 psi), for that matter.


To get the most benefit out of these lower pressures, you need supple tires. A stiff sidewall takes more energy to flex, so the tire will be slower. And since the sidewall is stiffer, it also will be less comfortable. You could call it a “lose-lose” situation.

Professional racers have known this all along: As much as their equipment has changed over time, they’ve always ridden supple tires. They usually ride hand-made tubulars (above), but for the rest of us, supple, wide clincher tires now make it possible to enjoy the ride and speed of supple tires on any road.

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Eingeordnet unter Ingenieur, Mob

25 Jahre Shimano MTB Schuhe.

via Bike Rumor

DAS Problem mit den angeklebten Sohlen kann ich für meine Shimano MTB Schuhe, ca. aus dem Jahr 2000 bestätigen. Muss ich jedes Jahr beim Schuster neu kleben lassen, einerseits. Hält aber andererseits auch bereits fast 15 Jahre.

posted by Cory Benson – January 23, 2015 – 6am EST


It has been 25 years since Shimano first introduced their M737 mountain bike clipless pedal, and together with their M100 shoe, SPDs set the benchmark that all modern mountain bike pedals have been measured against. With Shimano Pedaling Dynamics, Shimano has since developed pedals that are lighter, better in the mud, and now adapted to everything from commuters and spinning classes to World Cup cross country and downhill racing. At the same time the cleat interface became the standard that the mountain bike cycling shoe industry has built itself on, as legions of other pedal makers have brought out alternatives.

To celebrate the SPD, Shimano is now releasing a 25th anniversary limited edition 5-series pedal and trail shoe combo, highlighting how the technology has evolved and both pedals and shoes have become specialized over the years. Join us after the break for a look at the shoes and pedals and to see how far they’ve come.


It’s hard to think that it has been two and a half decades since those first M100 shoes, but thinking back the designs and technology have come a long way. While the first shoes in 1990 were pretty basic, Shimano claims to have been one of the first to add ratcheting buckle straps and carbon soles, a couple of elements that have come to define high performance cycling shoes.

Shimano-mountain_bike_shoes_M100_1990 Shimano-mountain_bike_shoes_M163G_2015

Looking back through the design progression over the years from that 1990 shoe, it seems the new edition of the Trail/Enduro shoe takes more of its design cues back to a time when mountain biking wasn’t as divided into so many individual disciplines. The new SH-M163G shoe, which we covered back at Interbike (and before) in its all-black version, features Shimano’s latest shoe tech, including a Cross X-Strap to limit instep hotspots and a TORBAL reinforced polyamide midsole boosting overall stiffness. It looks to be both an affordable shoe and one that can perform well across a range of mountain disciplines.

Shimano_spd_25th_logo_grayscale Shimano_special-edition_PD-M530C_25Years_Pedal

The special edition PD-M530C pedal doesn’t differ from the standard SLX-level trail pedal either, except with a 25th anniversary logo laser etched on the body. And that’s not a bad thing. This is one of the best value pedals Shimano has made, with the slightly larger than average platform making it even more versatile.

With 25 years of design and technology behind them, that SPD cleat has remained the same, delivering a solid and reliable interface. With that the new limited-edition combo pack should deliver a functional and reliable shoe/pedal system. Pricing for the special edition set has not been released, but the standard M163 retails for just $150 with the M530 at just $65. Availability is slated for spring, so if you like the looks of the shoes and need a new set of pedals, reach out to your local shop and see when they can get you a set.

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Run. Forest. Run.

run forrest run

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Baramon. Keirin Track Bike.

3Rensho, Kalavinka und Baramon sind meiner Meinung nach die japanischen Keirin Rahmen Hersteller, die ein wirklich anprechendes Logo Design haben. Hier ein sehr schönes Baramon.

bara 2 bara 3 bara 4 bara 5 bara 6 bara 7 bara1 baramon 1

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Eingeordnet unter Gierige Räder, Japan, Mob

Keirin. Kumamoto. Poster

Verbindet den Stil eines klassischen Holzschnittes (Ukiyo-e) mit teilweise modernen Elementen aus der Jahrhundertwende 1900 mit dem Inhalt der Werbung für ein Keirin Rennen in Kumamoto im Oktober 2014. In einer Nebennopte wird angekündigt, dass das Stadium in Kumamoto das erste Keirin Statdium in Japan mit WiFi ist. Willkommen im 21. Jahrhundert.


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Eingeordnet unter Japan, Mob

10 Common Misconceptions about Randonneuring

via Jan Heine, Off the beaten pathPosted on by 


With Paris-Brest-Paris coming up this year, a lot of people seem to be interested in randonneuring. They like the idea of a challenging, but not competitive, sport. Many brevets feature great scenery, a sense of adventure, and wonderful people to ride with. Unfortunately, all too often, I hear people say: “It sounds wonderful, but I couldn’t do it.”In many cases, that isn’t true. Most randonneurs, myself included, are pretty average people. Here are ten common misconceptions about randonneuring:

1. It takes a huge amount of time.

Randonneuring is a sport that doesn’t require a lot of training. If you are a moderately fit cyclist and able to ride a century without much trouble, you can start randonneuring now.

Every year, the brevets are in sequence. The 100 km populaire is great training for the 200 km brevet. The 200 prepares you for the 300, and so on. Even if you do a “full series” ofpopulaire, 200, 300, 400 and 600 km brevets, that is only 5 rides a year. Most of them are one-day rides, with the exception of the 600. So your time commitment amounts to about 6 days a year, in addition to your normal riding and training. And if you don’t have that much time, you can just do the 200 and 300.

2. You have to be super-human to do it.

Riding 600 km in 40 hours may seem beyond what average cyclists can do, but like so many things, it just takes a little training. You build up to it, just like you built up to your first century. Fortunately, nobody starts with a 600, and the 200, 300 and 400 km brevets are great preparation for the “big one”. And remember that these numbers are in kilometers. Translate a 200 km brevet into 124 miles, and it sounds more do-able straight away.


3. You need a special bike.

Bicycle Quarterly has done a lot of research on what makes an optimized randonneur bike, but you can use any bike for randonneuring. One of my friends rode several seasons, including PBP, on a carbon-fiber LeMond (above). Another friend rode a 1980s Trek on many brevets, including a 24-hour Flèche Vélocio. You can ride any bike.

A true randonneur bike will be a bit faster, quite a bit more comfortable, and probably more reliable, but you don’t have to have one. Unlike racing, where a poor bike choice will have you dropped on the first hill, randonneuring can be done on almost any bike.


4. It’s only for cyclists who are fast.

The most prestigious randonneur ride, the 750-mile Paris-Brest-Paris, requires an average speed of 8.3 mph (13.3 km/h). Most cyclists ride faster than that. Completing a brevet within the time limit has more to do with keeping your stops short and planning ahead than with riding fast on the road.

5. It’s only for cyclists who are slow.

Randonneurs ride at all speeds. It’s not uncommon for the first riders to average 22 mph or more, while others ride at half that speed. Whether you like riding fast or slow, you’ll find plenty of company among the randonneurs. And unlike racing, there is no ranking, and no implication that the faster riders are superior to the slower ones.


6. It’s expensive.

Compared to most sports, it’s remarkably cheap. Most brevets cost between $ 10-60 to enter. You can use almost any bike. You’ll need some money for food along the way. Assuming you have a bike, you could do a full randonneuring season on less than $ 300.

It’s often best to pack your own food anyhow, since the food choices in rural America are limited (above). Sometimes you are lucky, though, and volunteers at a control serve homemade soup or chili!


7. It’s all about riding more miles.

It’s true that most RUSA awards require you to ride more miles. But randonneuring is a big tent, and anybody can find their own challenges and joys. For some, it’s riding a 200 km every month of the year. For others, it’s reaching those mileage goals. Others challenge themselves to improve their personal bests through the Cyclos MontagnardsR80/R70/R60 program. And yet others just enjoy riding with friends and discovering new courses. All are equally successful randonneurs.


8. Sleep deprivation is scary.

Riding through the night is a new experience for most cyclists, but with a little bit of planning, there is no need to ride when your head drops and your bike veers. Many randonneurs sleep every night even during long rides.

I find that after a long day in the saddle, I really enjoy riding at night. The glare of the sun is gone, the wind usually dies down, and the sounds and smells are different. There is much less traffic. And mountain rides under a full moon are unforgettable experiences. If I get sleepy, I pull over and rest for a while.

9. It’s dangerous.

Like most activities, cycling can be dangerous, and randonneuring is no exception. There have been some accidents. In some cases, courses went on busy roads that see lots of drunk driving. Most organizers now try to stay away from those. A few riders have crashed when they became too tired, yet continued to ride. Most riders now know better than to ride when they are too tired to do so safely. So choose your courses carefully and don’t push beyond what is reasonable, and you should find that randonneuring is safe.


10. You need to worry about complicated rules.

Randonneuring does have rules, but they all make sense: Obey traffic laws and don’t get lost or take shortcuts, and you’ve already covered 90% of what you need to think about on the road. The rules are on the books so that things are clear, and there are no ad-hoc decisions, but most of the time, riders don’t need to think about them.

Here is what randonneuring is in a nutshell: Cycling with like-minded friends, on beautiful roads, while challenging yourself to ride better than you ever imagined. How you define “better” is up to you. Better can mean faster, more miles, more fun, more… or a combination of the above.

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Hotel Cycle. Onomichi.


Onomichi U2, ein Shopping Center in einer kleineren Stadt an der Südküste Japans zwischen Osaka und Hiroshima. Onomichi ist bekannt durch den Film Tokyo Monogatari von Ozu, hat eine Shinkansen-Station,so dass der Ort sehr einfach zu erreichen ist und ist der Startpunkt der Shimanami-Kaido, also der (Rad)Verbindung über diverse Brücken und Inseln des Inlandmeeres nach Imabari auf Shikoku.

Dort gibt es das Cycle Hotel.

U2 0 u2 1 U2 2

Günstig ist anders, aber die derzeitige Wechselkursentwicklung spielt einem in die Karten.

Ein Top Startpunkt für Radtouren in Japan.

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Eingeordnet unter Japan, Mob