DE|EN

The most efficient
drive system in the world

more torque through pure muscle power -
without using electricity from the socket!

News

We are reinventing the wheel (drive)

With the unique Cyfly® drive system, we can increase the efficiency of the bicycle to an enormous degree. Using a gear which is directly connected to the crank, we can make better use of the cyclist's energy and produce noticeably more torque.

In principle, the foot pedal is no longer directly connected to the axis, but relies on a rear mechanism.

So we have a longer leverage without the requirement for a larger treadway. With Cyfly, we can achieve the torque of a foot pedal of more than 23 cm long with the pedal path of a standard foot pedal.

The torque obtained ensures both relaxed and rapid cycling.
Particularly in gruelling cycling conditions on mountains or when starting up, you can immediately feel the support of Cyfly. Even in low pedalling cadence, a good performance can be achieved with little effort. Long trips can therefore be mastered without the use of a battery and the daily commute to work can be handled without breaking into a sweat.

Cyfly is being developed for the market by our engineers. This year, however, the mechanism will go into series production, so it is expected to be commercially available in 2017.

Questions and answers about Cyfly

What is Cyfly?
Cyfly is a bicycle drive system which works in a purely mechanical manner and uses the cyclist's power more effectively to generate significantly higher torque. This means that Cyfly allows you to ride faster with the same amount of effort, or to ride with significantly greater ease at the same speed. The traditional gear train remains in use, and one simply uses a different ratio according to the riding conditions. Cyfly works entirely without electricity, so you achieve significantly higher performance under your own power.

How does Cyfly work?
Cyfly is a combination of gears and levers. In principle, one can say that Cyfly uses a lever extension to generate the same torque as an extremely long crank (with a length of over 200 mm). At the same time, however, the pedal only follows the path of a very short 165 mm crank. This allows you to achieve significantly higher torque at the cadence and pedal speed you are used to.

Where is Cyfly installed?
Cyfly is installed in the bottom bracket and replaces the complete crank unit of a normal bicycle. Cyfly comes installed with cranks, bearings and even the chainwheel. We take care to ensure that all components are produced with state of the art manufacturing technology.

Can I retrofit Cyfly?
Unfortunately a retrofit version won't be available initially, since the gear system requires some space for which we need a specially adapted bicycle frame. So Cyfly will initially only be sold as part of a new bicycle.

How much additional weight does Cyfly add?
After subtracting the weight of an XT crankset including axle and internal bearing of approx. 1000 grams, Cyfly comes to an additional weight of 1550 grams. In addition, we are currently allowing 350 grams of additional weight for the required frame connection. Thus the first series can be expected to have an additional weight of approx. 2000 grams. Thanks to the favourable weight distribution at the frame's centre of gravity, however, it has a positive effect on handling. And because of the significant increase in torque, this additional mass doesn't carry any weight in the truest sense, especially when going uphill.

When and where will I be able to buy Cyfly?
Cyfly is expected to enter production in late 2016 and will go on sale in 2017. But since this is a B2B product, it will first be shipped to the bicycle manufacturers (OEMs) and these will then decide when and where Cyfly will be available for purchase.

How much will Cyfly cost?
Since Cyfly isn't sold separately but as part of a complete bicycle, we are unfortunately unable to set the final price of the bicycle. But a look at bicycles equipped with gearboxes such as Pinion or Rolhoff gives you an idea of the expected future price category of Cyfly bicycles. Please note that Cyfly isn't a gearbox like the two aforementioned products, but rather a mechanical drive to increase efficiency.

Exactly how much more efficient is Cyfly?
Well, that's hard to say. Everyone applies their power differently when cycling, so we cannot specify a generally applicable increase in efficiency. But we are working on an empirical study with many subjects under medical supervision, in order to obtain an average value.
The tests performed internally to date, however, confirm a double-digit increase in efficiency and every subject notices the effect right away. This makes us very confident that the Cyfly product we developed really does provide a significant additional benefit for all cyclists.

Does this mean that I'll be twice as fast with Cyfly?
No, unfortunately it isn't quite that simple. Of course the increased efficiency has an effect on the speed. Applying the same amount of force as one would apply to a conventional crank generates a higher amount of torque, and one automatically selects a higher gear ratio and thus rides faster. However, air resistance plays a large role at higher speeds. One of test riders, for example, has an average speed of 24 km/h on a normal bicycle and a speed of over 27 km/h on the Cyfly on our track, and with the same heart rate at that. Taking all values into consideration, the difference suggests an efficiency increase of up to 40 %. Just look your performance values up at http://www.kreuzotter.de/deutsch/speed.htm, and you will see how much performance is required to increase your speed by just 3-4 km/h.
Of course one also feels the higher efficiency of Cyfly right away. Especially on hills or when starting out in a high gear and with a strong headwind, so whenever a lot of force is required.

What is efficiency anyway?
Efficiency isn't a term with a specific technical definition, but it's often used if we want to state that machine A has a higher performance under the same conditions as machine B. If one looks at the efficiency of a normal vehicle engine, for example, then the more efficient engine uses less fuel under the same driving conditions. Certainly there are other efficiency values, such as the efficiency often used in mechanical engineering. So if machine A has an efficiency of 30 % (to put it simply: output value = 0.3 * input value), and the efficiency is now increased by 40 %, then one obtains an efficiency of 42 %.
We actually use the term exactly the same way as in the engine example, in order to explain that one achieves a higher performance with the same "exertion" using the Cyfly, or respectively has to go to exert oneself less for the same performance. To put it another way, the Cyfly with the same gear ratio makes for a more relaxed ride, or one automatically selects a higher gear ratio and thus rides faster for the same heart rate.

Power or torque, what exactly is becoming more efficient?
In the cycling world one often talks about watts, so power. There are a few ways to measure power. A common method is using a strain gauge to measure the force transmitted by the spider. The torque can be calculated in this manner using the distance to the rotational axis. If one now takes the cadence into account as well, one can calculate the power: [Watt=N*m/s]
So torque and power are related and are very well suited to comparing the Cyfly with a normal crank.

How can it be that there is still so much potential for improving the crank?
Since the cyclist always pushes from above, the greatest amount of force is converted into motion at a crank position of 90° (3 O'clock). This is because the radial portion which acts on the bottom bracket bearings is lowest at this point. This is why most bicycle geometries are designed so that the muscles are working optimally and can apply the greatest amount of force at a crank position of 90°.
Cyfly makes significantly better use of the applied forces, especially at this important 90° position. At this position, the Cyfly is 1.4 times as long as on a traditional crank. Accordingly, a significantly higher torque is generated with the same amount of applied force. Now one could think that one could achieve the same effect by simply increasing the length of the crank. But this also increases the pedal travel, which in turn would increase the speed at which the foot travels. It is exactly this dependency which is the reason that standard cranks have a length of between 170 mm and 180 mm. In the Cyfly, however, the pedal nevertheless covers the same distance in one revolution as a normal short crank, so that the average foot speed remains unchanged.
This effect is easy to see by looking at a torque curve. In a static test, we measured the pulling force of the chain in relation to the angle while applying a constant load:

antriebeng

We give ideas wings

As engineers, we have a passion for improving the ordinary. That's why
we have been offering solutions at our engineering office since 2011 under the name Möve equipment & design, from concept to manufacturing from a single source. Our 25-person team brings our customers' wishes into reality on a daily basis. As passionate cyclists we are eager to bring our own ideas to realization with the Cyfly® drive and revolutionize cycling. Be a part of it!

You can find more news about Cyfly® and Möve Bikes at:

Contact

Möve Bikes GmbH i.G.
Felchtaer Str. 27
99974 Mühlhausen

T. + 49 (0) 36 01-88 88 70
F. + 49 (0) 36 01-88 88 769
E. info@moeve-bikes.de

Be the first to learn news about Cyfly
and Möve Bikes!