Tagesarchiv: 18. Januar 2015

MKS. Pedale. Japan.

MKS, ist, ähnlich wie Nitto, Soyo, Kashimax, Hatta, DID, Honjo und Soyo einer der kleinen und wenigen traditionsreichen Hersteller von Fahrradkomponenten der die letzten zwanzig Jahre irgendwie überlebt hat. Die Produkte sind von ausgezeichneter Qualität, mal teuer, mal weniger, je nach JPY/Euro Wechselkurs und wenig innovativ: Nitto verwendet kein Carbon; MKS baut (fast keine) Systempedale, Hatta ist wenig präsent außerhalb von 1“ Gewindesteuersätzen und Vierkant Innenlagern und Kashimax – ich weiß es nicht. Alle Hersteller liefern in die japanische Keirin Szene, da sie NJS zugelassene Komponenten im Programm haben (bis auf Honjo, die machen Schutzbleche), aber ob das reicht um zu überleben? Diese Unternehmen haben einfach Glück, dass klassische Räder wieder in sind bzw. sind in andere Bereiche diversifiziert.

David von Positivo Espresso hat letztens einen guten Bericht über seinen Besuch bei Gokiso/Kondo Machinery geschrieben, hier liegt der Fall etwas anders da Gokiso traditionell in die Elektronik und Luftfahrt liefert und in Radkomponenten diversifiziere. Aber das Schema eine kleinen, japanischen Unternehmens mit vielen älteren und erfahrenen Angestellten, sehr unauffällige Gebäuden die Nischenprodukte in höchster Qualität herstellen ist ähnlich.

Anbei ein Bericht via Jan Heine von MKS aus Off the beaten path


During our recent visit to Japan, we had the privilege of visiting Mikashima Industrial Company, better known as MKS, the makers of bicycle pedals. We had expressed an interest in MKS to our trading company. Fortunately, the MKS’s president, Toshiyuki Ogino (right), had heard about Bicycle Quarterly and was also interested in meeting us.

MKS is remembered by many for making pedals for SunTour. Those wonderful Superbe Pro and XC Pro pedals (some even with Charlie Cunningham’s GreaseGuard grease injection system) all were made by MKS.

It was a 1-hour train ride from Tokyo to Sayama-Ga-Oka, where the MKS factory is located. We were picked up by our guide in a brand-new Subaru – he explained that MKS makes headrests for Japanese-built Subarus, hence all company cars are by that maker.

Before we started our tour, we were given MKS caps to show that we were legitimate visitors as we walked around the factory. (Employees all wear company shirts or jackets.)


We were surprised by the wide range of products that MKS makes. Bicycle pedals are only half their output. The remainder appears to consist of parts for the automobile industry.


We were asked to not take photos during the visit, which is too bad! It would have been nice to take you on a virtual tour of this impressive factory with its large heat treating ovens, huge presses, forging hammers, polishing machines…

As we enter the first building, one machine is stamping toeclips out of large sheets of steel. It reminds me of making shape cookies with cookie cutters. The toeclip shapes fall into bins, while the left-over steel sheet now has toeclip-shaped holes. It’s fun to watch.

Another machine is forging parts for truck diesel engines. We suspect they are fuel injectors, but it’s too loud in here to ask many questions. And what is “fuel injector” in Japanese, anyhow?

The polishing machines are impressive, with colorful stones rotating in cone-shaped barrels as the parts are polished. The heat treatment ovens are state-of-the-art, as Stefan, our Taiwanese engineer who has joined us for our meetings in Tokyo, confirms. (He used to install these ovens for a living before moving to Taiwan to work in the bike industry.)

The assembly building is much quieter. One room has an assembly line for the aforementioned Subaru headrests. The next room has a single employee assembling the top-of-the-line Keirin pedals. He is wearing white gloves, and next to his workstation are small bins with paper-thin shims. The pedals are equipped with cartridge bearings, but the end play is adjusted with these shims, in 0.03 mm increments. (That is 1/1000 of an inch!) The employee screws in the locknut, checks the play, then removes the nut and installs the next-bigger shim. He repeats the process until the bearing adjustment is perfect. It’s labor-intensive: While we watch, we see only a single pedal being completed and put aside for packing.


We pick up the pedal. Feeling the bearings spin oh-so-smoothly is an object lesson in quality. I want to get a set to keep on my desk and to play with from time to time, to inspire me to insist on the best quality as I am working on our own Compass components.


The pedals have many neat features. The cages are cut away to save weight, yet they support the feet in all the important places. There is a lock for the toe strap, so the old technique of twisting the straps as you feed them through the underside of the pedals isn’t necessary – the straps will stay in place no matter how often you open and close them. Even with a spindle made from strong CrMo steel, the RX-1 pedals are as light as the classic Campagnolo Super Record pedals with their titanium spindles. And the cages are replaceable, since they’ll wear over time where your cleats touch them.

Of course, these pedals are approved by the NJS (Japanese Cycling Association) for Keirin racing. NJS-approval is an interesting thing: it’s intended to keep the races safe and the playing field level. Every part of the bikes used in these track races must be tested for safety and approved. So for you as a rider, “NJS-approved” means that the pedals are safe even under the strongest riders. (NJS doesn’t say anything about performance or bearing quality.)

The next, much larger room houses the assembly for the less expensive MKS pedals. The contrast to the quiet, unhurried pace of the top-of-the-line pedal assembly is remarkable. The less expensive pedals are assembled by hissing pneumatic tools. The finished pedals drop into buckets with loud clanks. Even here, an employee checks the final bearing adjustment by hand. When we feel a pedal, it’s clear that these pedals will need to “break in” as you ride. The Keirin pedals, on the other hand, have silky-smooth bearings right out of the box.


“Right out of the box” – once you figure out how to open the box! You open the top flap, and then flip open the box like a book. Each pedal has its own little compartment. The smooth lacquered paper stock and tasteful finish ensure that you’ll find a reason to keep this box even after you have installed the pedals.


Keirin racers use toeclips and straps, so MKS also makes what I think are the best toestraps. (And yes, I’ve used Binda Extras and most other famous brands of the past.) Two layers of glove-soft leather sandwich a layer of anti-stretch Nylon. That way, you don’t have to cinch down your toestraps until they cut the circulation in your feet. Adjusting them to a comfortable snugness is enough to prevent your feet from coming out of the clips even when you climb out of the saddle (or sprint in a Keirin race).


MKS even makes cleats that work with modern 3-bolt LOOK-style shoes, removing one further barrier of entry into the world of toeclips and straps. (They also make more affordable toestraps with just a single layer of high-quality leather, as shown above.)

I am on the fence about toeclips and straps. On the one hand, I love the classic appearance and incredible quality of these MKS components. I have a set of touring bicycle shoes that work with toeclips and allow me to walk. But for all-out efforts, I prefer a more rigid connection to the pedal, which requires cleats that make walking difficult. So for randonneuring, I prefer SPD-style pedals and shoes.

If you have several bikes that you enjoy for their different feel and ride, at least one of them probably should have traditional pedals. I am tempted to put a set of the MKS Keirin pedals on my Alex Singer camping bike.


For riding in street shoes, half-clips are a great option. They locate your feet during the downstroke (which is where you put out all your power anyhow). And on bumpy roads, they prevent your feet from sliding off the pedals. MKS makes these lovely “Cage Clips”, which are welded from steel rod, rather than stamped out of flat steel sheet. Not only are they beautiful, but they also don’t have sharp edges that can scratch your shoes. And they are made from stainless steel, so they won’t rust even if you scratch them up a bit as you start from a stop with the pedals flipped upside down.

After the factory tour, we meet with the engineers and the president of MKS. We decide to import some of the pedals, straps and cages that MKS already makes. And we hope to collaborate on future projects. Wouldn’t it be nice if we had a true randonneuring and cyclotouring pedal designed for long-distance comfort and longevity? The adapted mountain bike components we use today have mud clearance we don’t need, and the down side is a small cleat that puts more pressure on our foot and wears out quicker than is ideal.

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Neue Campagnolo Delta Variante entdeckt.

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Schaltung für Dummys.

via Cycling Tips

Beyond the big ring: understanding gear ratios and why they matter

There is more to the gearing on your bike than simply the size of your big ring. To get the most out of your gears, it serves to pay attention to the gear ratios produced by the combination of the chainrings with the rear cassette and tailoring them to suit your riding needs. In this post, CTech editor Matt Wikstrom takes a look at how to make sense of gear ratios.

Over the past decade, the number of gears on road bikes has steadily increased. Current groupsets now provide up to 22 gear combinations produced by two front chainrings and 11 rear cogs. That should be enough to contend with just about any terrain, but there is no prescription for perfect gearing. Rather, the individual must determine which gear ratios suit his or her riding style and needs.


Before the advent of the chain-drive, cyclists determined that the size of the drive-wheel had a profound impact on the speeds that could be achieved. Penny-farthings were not designed with a huge front wheel for aesthetic reasons — the massive circumference allowed higher speeds provided the rider was strong enough to turn the gear.

The introduction of the chain-drive improved the efficiency of the bike because gears could be used. By combining a large cog on the cranks with a small one on the wheel, a single turn of the cranks produced multiple revolutions of the rear wheel, so it could operate just like the massive drive-wheel of a Penny-farthing.

Calculating the number of wheel revolutions produced by a bike’s gearing is simply a matter of determining the ratio of the chainring to the rear sprocket. For example, when a 53T chainring is paired with a 12T cog, it has a ratio 53:12 or 4.42 — that is, the rear wheel rotates 4.42 times for every rotation of the crank. In contrast, a 39x25T selection produces a gear ratio of 1.56.


A road groupset can offer a variety of gear ratios ranging from 1.21 to 4.81 in increments of 0.15-0.40. Rather than trying to understand the significance of gear ratios directly, they can be transformed into more meaningful values in one of two ways.

The first method is to relate the gear ratio to wheel size by multiplying the gear ratio by the diameter of the wheel (Figure 1A). In the case of a road wheel, 27 inches can be used for simplicity although the true diameter of a 700c rim fitted with a 23mm tyre is more like 26.3 inches. The resulting value, gear inches, is the equivalent diameter for a direct-drive wheel (like the front wheel of a Penny-farthing).

Put another way, gear inches provides the diameter of a wheel that has a circumference equivalent to the distance a geared bike will travel with one turn of the cranks and the chosen gear ratio. Thus, riding a high gear ratio such as 53x12T is equivalent to pushing a wheel with a diameter of 119 inches. In contrast, a low gear ratio like 39x25T is equivalent to a 42-inch wheel.


The second method, meters of development, is calculated by multiplying the gear ratio by the circumference of the wheel (measured in meters, Figure 1B). This value represents the distance the bike will travel with one crank revolution. Thus 53x12T yields 9.28 meters of development compared to 3.28 meters for 39x25T.

Gear inches (or meters of development) are typically presented in a gearing chart or graphed so that various combinations can be compared (Figure 2). My introduction to gear charts came with BMX racing where they proved invaluable for fine-tuning gear selection to suit the track and weather conditions. Track riders will do the same, swapping the front chainrings and/or the rear sprocket to increase or decrease the gear ratio in increments as required.

The important thing to note is that even minor differences in a ratio (e.g. 1 gear inch) influence how easily the bike can be accelerated or the maximum speed that can be attained.



In practice, road riders typically don’t pay much attention to gear ratios due to the abundance of choices available to them. However, there is still considerable value in fine-tuning the range of gear ratios at your disposal to maximise their utility.

I typically see riders deciding on their gearing on the basis of the largest or smallest gear ratios. Some will insist on an 11T cog, however the only time they ever use it is on a steep descent. Such thinking also fuels the debate on the merits of standard (53/39T) versus compact (50/34T) cranksets but the two offer comparable ratios. Indeed, pairing an 11-23T cassette with a compact crankset offers near-identical ratios to a standard crankset coupled with a 12-25T cassette (Figure 3).


There is a subtle difference between standard and compact cranks though. As shown in Figure 4 below, the rate at which the ratios increase is greater for standard rings than compact rings. For example, the ratios for the 11-15T cogs increase at an average rate of 7.0 gear inches/tooth for a 53T chainring compared to 6.6 gear inches/T for a 50T chainring. This difference defines the true distinction between the two cranksets by generating a different feel to the gearing at the high end.

Deciding on one over the other is difficult to do without some experience with each, but in general, the lower rate of development offered by compact cranks will suit novices and enthusiasts while racers will prefer the extra grunt offered by standard rings.


There is another consideration. Every crank and cassette combination suffers from some redundancy that reduces the number of discrete ratios on offer. A standard crankset paired with an 11-speed 11-25T cassette offers 15 discrete ratios (Figure 5A); by contrast, compact cranks paired with the same cassette afford 16 discrete ratios (Figure 5B). The difference is dictated by the combination rather than the size of the chainrings since 16 discrete ratios can be achieved by pairing an 11-28T cassette with a standard crankset (Figure 5C).



So what makes for perfect gearing? Ideally, you want a combination where every upshift and downshift delivers a change in gearing that perfectly suits your legs. Riders that like to spin are likely to prefer small steps while those with more strength and a preference for a slower cadence will want bigger steps.

Thus, the former will enjoy compact rings and/or a straight block (which provides cogs in 1T increments) while bigger chainrings and/or larger increments in the cassette are likely to suit the latter. Bear in mind though, the suitability of the gearing is subject to your form and the terrain.



Ultimately, gearing is a personal choice and every rider should have the freedom to decide the matter for him/herself, but it will involve some experimentation. Fortunately, groupset manufacturers offer plenty of choices with 11-speed transmissions and compact/semi-compact/standard chainring combinations. The latter is further helped by new crank designs that allow compact, semi-compact, and standard chainring combinations to be interchanged.

It is futile judging the value of a particular chainring and cassette pairing on the basis of a single ratio. A 53T chainring will always offer a higher gear ratio than a compact 50T chainring but the two offer different rates of development, which ultimately dictates how the gearing evolves over the range of the cassette. At the same time, devoting some consideration to the overlap in gear ratios between the big and small chainrings may extend the versatility of the gearing.


It won’t be long before bike computers are paired with electronic groupsets to collect data on how much time is spent using each gear ratio. At the same time, there is also the prospect of sequential shifting for road groupsets. Perhaps these and other innovations will usher in a new era of intelligent gearing?

What sort of gearing do you prefer? Compact or standard crank? Or perhaps a mid-compact? Why have you got the gearing setup you’ve currently got? Is it simply about the range of gears for you, or something more?

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Schnelle Räder. Leichte Räder.

via Velonews

Editor’s Note: This excerpt is adapted from the book FASTER: Demystifying the Science of Triathlon Speed by Jim Gourley and republished with permission from VeloPress. Learn more about the science of triathlon at freetrispeed.com.

Let’s clear something up. There is no such thing as a “fast bike.” Bikes are neither fast nor slow. Bikes are shiny or expensive. Bikes have a lot of mass or a little. Without a rider, they are stationary. Physics holds a bike in place until you get on it and start pedaling. Even then the bike may not necessarily be fast. Of all the equipment on your bike, your legs are the most critical component. There are plenty of nice bikes on the road that are being ridden slowly.

But more insidious than inaccurate vocabulary is a simple overestimation of how much bike weight matters for most riding.

In FASTER, I show the math that explains why just a degree or two of incline makes riding a bike feel so much harder. Riding up a hill, it may seem more important than ever to dump any and all extra mass we can from our bikes. That’s the allure of a carbon fiber bottle cage, an upgrade to carbon fiber cranks, handlebars, stem, carbon saddle rails, or wheel spokes. Five grams here, 10 grams there, it all adds up, right? Pretty soon, you’re 500 grams lighter. That’s half a kilogram!

True. But such upgrades could easily total $500 or more, which is also half a grand. Is it worth it?

Not exactly.

A good approximate difference between an entry-level aluminum bike with a decent set of components and a top-of-the-line carbon model with some of the lightest components on the market is just shy of 3.25 pounds.

Was the weight loss worth it?

Let’s find out. Take a hypothetical rider and have her ride two bikes up a hill at the same speed. The first bike weighs 15 pounds and the second bike will shave off the 3.21 pounds to weigh in at 11.79 pounds. For each test, we’ll have her ride at 15 mph. Everything is constant, except for the bike, so what we ought to see is a reduction in the power required to get up the hill. That’s the real test of your savings.

Refer to the second image, above, for a graph of the results.

If you’re having trouble telling what the difference is, save yourself the eyestrain, because there isn’t much — that’s the message.

But pro athletes use the lightest equipment they can, so there must be something to it, right?

Remember that professional athletes operate in an entirely different environment than the rest of us. They are all very close to each other in terms of fitness, and they are also all very close to being the absolute best a human being can be.

Beyond that, our result also makes intuitive sense: 3.21 pounds is just over 2 percent of the total weight of our 150-pound cyclist and 15-pound bike. Ten watts is 2 percent of the 500-watt power requirement to maintain speed up a 10 percent grade. Because the weight-to-power savings ratio is linear, we should expect that one-to-one relationship.

The implication is a bitter pill, though. If you want to reduce the power requirement by 1 percent, you have to reduce the total mass that’s moving up the hill by 1 percent. And because you’re moving both your body and the bike up the hill, a measly 1 percent equates to a whole lot of grams before you see returns on your carbon investment.

In short, you’re much better off upgrading your legs and dropping body fat through proper training and diet. In fact, losing unnecessary weight would have a dual impact on your power and speed. As weight decreases, the amount of power required to maintain a certain speed will also decrease. At the same time, the amount of power you are capable of generating should actually increase. This is because oxygen uptake is related to body mass and improves as fat is lost.

Wattage vs. time

If the power argument doesn’t quite satisfy you, we can look at it another way. Let’s answer the question you really care about: How much faster does it make me? After all, you win races by saving time, not watts. Let’s see what will happen when our hypothetical rider rides bikes of varying weight up different hills. We’ll hold power at a constant 200 watts and have her ride up a 1-mile climb at seven different grades (1–7 percent).

Let’s look at the difference between 15-, 16-, 17-, and 18-pound bikes, with the 18-pound bike serving as the baseline. Because of the complexity involved, we’ll eliminate air resistance and analyze the impact of weight reduction only. How much time do we save?

A graph of the results is in the third image above.

Read it and weep, weight watchers.

Look at the far right of the graph. Take 3 pounds off your bike, pedal at a constant rate of 200 watts, and you’ll get to the top of a 7 percent climb a whole 7.5 seconds ahead of the competition. A 1-pound advantage only puts you ahead by 2.5 seconds. Over the course of an hours-long race, a few seconds per climb is not a significant advantage.

Keep in mind that the advantage only holds when the climbs are long and steep. Courses with fewer and shorter ascents will keep the difference small.
Read more at http://velonews.competitor.com/2014/08/news/bike-weight-myth-fast-bikes_339880#5Z4PyRiZJd6WOBRQ.99

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Speichen Windup

Typisches Einspeichproblem und eine gute Lösung dafür.

via Velo News

Es gibt von Velo News eine ganze Reihe von hilfreichen Videos , einige besser, andre schlechter.

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Factory Five. Kettenblatt.


via Factory Five

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Presta zu Autoventil.

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