Classified hub inventor Roëll van Druten

Classified's Origin Story with Dr Roëll van Druten

Ever wondered when, where and how Classified's Powershift Technology came into being? We sat down with the inventor of Powershift Technology, Dr Roëll van Druten, to discuss the origins of Classified, the journey from inception in 2013 to today, and what motivated him to reimagine the drivetrain as we know it.

Classified: Thanks for taking the time to sit down and discuss the origins of Classified. Firstly, please tell us a bit about yourself.

Roëll van Druten: No problem. My name is Roëll, I’m from the Netherlands, and I’m the CTO and co-founder at Classified. I have a PHD & Postdoc in Drivetrain & transmission technology, and I worked in the automotive industry for 25 years. And now I make bicycle drivetrain components.

When did you start cycling?

I’m Dutch, so I think I was about 3 years old! Mostly I’m more of an urban cyclist these days, riding my Powershift equipped E-bike.

How did you develop the first Classified hub? What year was it and where were you?

It was around 2013 when the first prototype hub was developed. Interestingly it was actually a mechanical actuation back then. Our first focus was to optimise the efficiency of a planetary gear set in the bicycle industry, as we knew this would be a crucial development for performance cyclists. We initially developed the hub at the High Tech Campus in Eindhoven. It is an ecosystem of 300 high tech companies and a research facility of Phillips, so a good place to develop a product. The first hub was actually intended for mountain bikes, before we started working on road and gravel. This is because Sram had just made the switch to 1x in MTB, starting the process of killing off the front derailleur.

How did you fund that early development?

It was self-funded, with a few small grants. I was still working in the automotive industry full time, for Punch Powertrain, so I only worked on the hub part time. I had one employee at that time so we were able to keep costs low. The first employee, Jeroen van den Brand, is a fellow engineer, a seasoned cyclist, and a confirmed bicycle geek! He is also still involved with Classified, which I think says a lot about the company. 

What was your motivation? Why did you feel the need to reinvent the bicycle drivetrain?

Sram’s move to 1x for their MTB drivetrains was the start. We didn’t like the large steps in gears and missed the ‘bail out’ option of a front derailleur. At the same time we were also fed up with the front derailleur and how often it would cause problems. However, removing the front derailleur without replacing it with a better solution removed key functionality and control. So we started to imagine what it could be like to have a front derailleur like shift change, but one that was much faster and more reliable. This would be the ultimate weapon for every type of cyclist. 

Your background is in the automotive industry. What have you taken from that sector into Classified?

I was the Chief Engineer for designing 2 new electrified dual clutch transmissions at Punch Powertrain, working with a team of 150 engineers. We took the automotive way of working into Classified. First we set requirements, then validated those requirements, then go through systematic design steps and do multilevel system testing. In the automotive industry you develop your testing process alongside your product, which is also how we do things at Classified. At Classified we must have designed 10 test rigs by now! And of course we use CAD optimisation tools and gear optimisation tools, just like the automotive industry. We also work together with automotive engineering and manufacturing companies for electronics and software development, as well as part production according to PPAP processes. We took some of the tools, processes and ways of working, and of course some good connections. The actual technical solution of the clutch system (in the hub) and the wireless connection is a completely new design for bicycles.

Do you have a lot of experience regarding patents?

Yes, I also have a strong background in building patent portfolios. It’s very important to have freedom to operate and to patent your inventions. So it’s crucial that we patented everything at Classified. It’s quite interesting, for both the automotive and bike drivetrain industries, that there are less than 10 main players when it comes to patents, but they're all very good at it, so it’s quite competitive. 

We knew from our automotive background that a 99+% efficiency was possible, we just had to prove it to the bicycle industry. We developed the product, we built the test rig, and then we measured it. We proved that the hub is 99.8% efficient in the 1:1 ratio (direct drive) and 99.2% efficient in the 0.7 ratio.

How and where did you meet Classified co-founder Mathias Plouvier?

Mathias and I worked together at Punch Powertrain. We worked together on a deal with the Stellantis group to supply all transmissions for PSA. We worked well together on that transaction, Mathias setting up the corporate work and handling the commercial side, and me as the technical lead. It was a big success, so we carried that relationship and those roles into Classified, with Mathias as CEO and myself as CTO. Mathias is a huge bicycle fan and has great connections in the industry, especially in Belgium. So we created a bicycle company that was both Dutch and Belgian - two huge biking countries. Our Headquarters is now located in Antwerp and our technology centre is in Eindhoven.

When was Classified created?

This was 2018, when the hub prototypes were more mature, including a wireless electronic actuation. This is when we founded Classified and took some funding to develop the product further and to bring it to market. We had 5 employees at this stage.

How did early development go?

Getting funding was crucial. Not only did it mean validation in the market, but it meant we were able to develop the test rigs and create a supplier base. Not many people know it but 90% of our parts suppliers are in Europe, which we’re very proud of. We set up assembly in Turnhout in Belgium (exactly half way between Antwerp & Eindhoven). In 2020 we launched the first product to the market. It took 2.5 years to come to market, not including the 7 years of development prior to that. We had 15 employees at this point, but we grew very quickly and were able to set up a sales and marketing department. And then in 2022 we outgrew our Turnhout ‘startup’ office, and decided to move headquarters to Antwerp and R&D to Eindhoven.

Tell us about testing the efficiency of the hub. It must be nice to see your theories proven in black and white?

Classified is the first bicycle company to take an internally geared hub to a sportive segment. We knew from our automotive background that a 99+% efficiency was possible, we just had to prove it to the bicycle industry. We developed the product, we built the test rig, and then we measured it. We proved that the hub is 99.8% efficient in the 1:1 ratio (direct drive) and 99.2% efficient in the 0.7 ratio (read the test summary here, and full white paper here).

We searched the world over for a test rig to measure our hub, but we couldn’t find an accurate enough option. We had to develop our own test rig with an experienced test rig development company in Eindhoven, which also took two years. Our specialist test rig gives us a measurement accuracy of 0.1%. It is not possible to reach the needed accuracy to test the hub efficiency using standard rollers.

We believed that this technology could be brought to the bicycle market. We knew that small chainrings and sprockets should be avoided, so we created a system with a reduction gear, which means that the rider will always be on one, larger chainring. It is very satisfying to see our assumptions proven in concrete data. It’s been years of research and development. The team has worked very hard.

And it’s also very encouraging that we have had professional teams testing the hub for a number of years now, and their feedback has also convinced us that the complete setup is very efficient. Real life validation is important alongside the test data. But next to the efficiency improvements, one the biggest advantage is the lightning fast shifting under full load. It’s an extra weapon in every discipline, which is also something that the pro riders have also reported.

Updating the MTB Lexicon with a new verb:

to Power·shift [Powershifting] {Verb}:
(also: the new benchmark in shifting gears)

1. To shift gears under full load within 150 milliseconds
2. Maintain valuable momentum during climbs and transitions, or before an attack

Classified’s unique 2 speed gear hub allows riders to jump through 46% percent of the gear range, or the equivalent of 2 or 3 rear derailleur shifts, within 150 milliseconds. As such, ‘Powershifting’ is quickly becoming the go to term for maintaining momentum on the trails.

Tests undertaken with pro riders showed a far greater use of the powershift hub gear as opposed to the rear derailleur, leading to an overwhelming increase of momentum through transitions.

“The feedback of professional riders is very promising and brought us even better insights into the enormous potential the product offers. Extending our range further into off-road space with the mountain bike hub confirms Classified’s vision to be a technology that is compatible across all cycling disciplines. We are extremely excited about the possibilities the new product brings and its ability to enhance the existing MTB drivetrain market." says Mathias Plouvier, CEO and co-founder of Classified Cycling.

CTO Roell van Druten adds “we are very proud to bring Powershift technology to mountain biking. With an ultimate gear range of 530%, the Powershift Boost hub combines a high-grade, one-piece compact steel cassette (11-40t) with a larger chainring, improving the overall durability of the drivetrain.”

Van Druten goes further to explain the benefits of the new system: “Using the Classified hub with an 11-40t cassette and a 34t chainring results in the lowest drivetrain ratio of 0.58. To achieve this ratio with a traditional system the user would have to use a 30t chainring. Using a smaller chainring in a traditional system lowers the efficiency and durability of that system due to the higher chain forces. The more compact Classified cassette also allows the use of a shorter derailleur cage, increasing the robustness of the drivetrain alongside the efficiency.”    

The Ringshifter:

The next generation of shifting, this sleek, fully wireless handlebar control provides unrivalled shifting performance with the lightest flick of your thumb. The Ringshifter can perform 10,000 shifts before needing to be easily recharged with the provided magnetic USB cable.

Featuring a unique magnetic spring back mechanism, the Ringshifter delivers unparalleled durability and a smooth, responsive feel. The functionalities of the Ringshifter can be customized to meet the individual needs of every rider.

Can you tell us which pro teams are testing?

It is public knowledge that UNO X have tested Classified, and of course that Victor Campenaerts raced with Powershift Technology in the Classics. Others are testing, I just can’t say who yet!  All of our ambassadors also tested the system before coming on board. Some of the best cyclists in the world - Tom Boonen, Philippe Gilbert, Anna van der Breggen, Marcel Kittel and Ándre Greipel - they all tested the system before becoming involved. And they know a thing or two! And what’s interesting is that after testing, most asked to invest in the company. It was purely the strength of the product that convinced them.

Biggest challenge of the last 5 years

During Covid, there were massive disruptions to the whole industry. Both with very low stock to very high stock. It disrupted our business a lot, as we launched the product to market, and then the lockdowns happened. It was especially hard in the low stock days because we had to wait for integration with OEM brands. But we pushed through, and now we work with many OEM bike and wheel partners.

Removing the front derailleur without replacing it with a better solution removed key functionality and control. So we started to imagine what it could be like to have a front derailleur like shift change, but one that was much faster and more reliable. This would be the ultimate weapon for every type of cyclist.

What has surprised you about the journey over the last 5 years

We actually started developing the hub for mountain bikes, which is actually the heaviest application because it has the highest torque. An MTB rider doing 300 watts will create more torque than a pro road rider doing 1000 watts, thanks to the small chainring and big cassette and lower speeds. But in the end it turned out to be a good thing that we started with MTB, because when we switched to developing the road and gravel hub, it was already very durable.

Wheel development was also a surprise. We never set out to be a wheel company. But through wheel development and working with the great wheel partners in the world, we are able to supply some of the best wheels in the world, both through our own Classified wheels and also through our wheel partners.  

What’s your dream for the future of Classified? 

Building an excellent, international team of engineers and cycling enthusiasts, to make next level bicycle drivetrain products that enhance the rider’s experience. And then getting into every market segment with our hub technology, and partnering with the best companies and riders in the world.

What’s your dream for the future of the cycling space?

Maintenance free drivetrains will be the future. Highly efficient and light drivetrain components, which are connected to all of your devices and integrated in a complete bike ecosystem. There’s so much innovation still to do, it feels like we are just getting started!

Thanks Roëll. Finally, we always ask this of athletes and users, but what is your favourite thing about Powershift Technology

That’s an easy one. The smile on a rider's face when they do a powershift for the first time. It always happens, the same ‘this is cool’ reaction. I love it. So please enjoy your powershifting!

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