Feel the Power

We have created the Extendable Crankset. A unique crank design that increases pedaling power. How much?

Between 25% and 35%

How does it work?

Drag over the image to see how our patented system works:

With the help of Custom4.us we have carried out an in-depth evaluation of our system.

We compared the performance of a bike with the traditional crank system and another with two variants of our system. The test was done with a trained cyclist who tried our cranks for the first time.

Custom4.us obtained records of simultaneous measurements on loads of 2, 3 and 4 w/kg. These measurements were made with specific equipment for torque analysis, EMG and kinematics

Some more data.

Torque: “the maximum and minimum torques during pedaling increase with respect to the system for the same power demanded in a very significant way (25-35%)”.“The system of extensible connecting rods manages to manifest more force throughout the entire pedaling cycle, which would be equivalent in the case of maintaining the power to reducing the cadence, or vice versa.” Muscular electrical activity: “the electrical activity is not significantly different, so we can confirm that this system generates more force with the same average electrical activity, although the maximum is greater”. This report analyzes other factors, and makes some recommendations aimed at improving results, fields of application and possible guidelines in future tests.

What are Extendable Cranks?

The pedals with our Extendable Cranks allow you to increase between 25% and 35% the pedaling force, or in other words, reduce the same percentage energy (effort) required when pedalling.

This is achieved by the simple application of the law of the force of the lever but also, making it compatible with a round pedaling (perfect circumference), and therefore without harming the cyclist’s biomechanics.< /h3>

What advantages does it have?

Our system in detail

Numerous media have been made echo of our Extendable Cranks System

We are looking for stores, distributors or specialized companies interested in our product.

If you want to be part of Cranks Extensible, do not hesitate to contact us.

We will be happy to answer any questions.

You can also call us or write to our contact email.

BIKE INNOVATIONS, SL., Polígono I. Mutilva Baja,
Calle V, nº 26, 31192. Mutilva. NAVARRA – ESPAÑA

Technological Partner:


Fernando Irujo manages to make the pedaling of a bicycle 35% more powerful thanks to his invention: extendable connecting rods that he has already patented. “With that, anyone can win the Tour de France,” he tells ALnavío. And it’s not just him saying it. It is also said by a biomechanist for the International Cycling Union.

The trick of this Navarrese is something much more sophisticated. Something that he himself invented and patented. An extendable crank that increases pedaling power between 25% and 35%.

Irujo , raised among tools -his grandfather was a blacksmith, his father a mechanic and he a mechanic-electrician-, devised a pedaling system to help a sister-in-law climb a hill with her bicycle. That sister-in-law had polio, a disease that affects mobility, so with a normal bike it was impossible for her to climb a slope.

Then Irujo began to think. Round and round came the eureka: the solution to his sister-in-law’s problem was the law of the lever. “The longer a lever is, the less force you have to apply,” he explains.

To apply that law of the lever, Irujo, inspired by the mechanism of a liquid pump, got the pedals to enter and leave the circumference that holds them. In this way, the diameter remained the same in all parts of the route. This is how she achieved the extendable connecting rod and that her sister-in-law could climb the desired hill.

I don’t know Don’t worry if you don’t get it, because no one did at first. “No one. Not even the engineers.” And it is that in addition to the law of the lever, Irujo relied on other rules of physics to promote his invention.

Comment that another of the things that enhance the system is the distribution of forces. This is not the same as a traditional bike. Some traditional pedals generate a 360º circumference. 180º forwards and another 180º backwards. With the extendable connecting rod, the front part is longer. It exceeds 200 degrees, thus being the highest speed.

Its use is universal for both vehicles and users: “The same is for disabled bicycles, for road bikes, mountain bikes… And for anyone who has a bicycle”