BlackCatBone Bikerumor Tech Speak (1)
David on the beach after EWS Puta Ala

When David first pinged us with an offer to feature his bike as a Reader’s Ride, what seemed like just another Di2 equipped mountain bike turned out to be anything but. It just so happens that not only is David half of the enigmatic BlackCatBone, but he is also the same David I have been following on forums talking about his electronic shift system that he has been using to race enduro.

We’ve featured some of BlackCatBone’s work before with their Lucy single sided, rigid fork, and their electronic grip shift prototype, but it turns out there is much more to BlackCatBone than meets the eye – like their very own electronic drivetrain currently in development, code named – Rollìa.

Check out electronic shifting, suspension control, radical road bike geometry and the evolution of the bike, all from BlackCatBone’s point of view after the break.


Bikerumor: What is the current state of BlackCatBone, and who all is involved?

BlackCatBone: Right now BlackCatBone is focused on engineering. We’re currently developing projects for other companies, most of them in the cycling industry, but not only. For example we’re also working for a steel manufacturer on an electronic wear control for metal sheets on construction trucks and mining machinery.BCB is just two people, Gerard and me.

Tech Speak: Talking Electronic Shifting, Suspension Control, and Bike Evolution with BlackCatBone

Bikerumor: Are you still selling the Lucy Fork and any other parts? What parts are currently available, and where can consumers buy them?

BlackCatBone: We’re not selling products to the general public at the moment, just small runs ordered by certain frame builders we used to work with. We’d love to do so as we still get lots of emails from people interested in buying things we developed three years ago.  All those products have been revised, we have refined them and there are test prototypes of them so we are sure they would be doing well in the market. Why then, we don’t just make them available to people?

Tech Speak: Talking Electronic Shifting, Suspension Control, and Bike Evolution with BlackCatBone
BCB 12 Bar Lefty steerer adapter.

The BCB Lucy, the 12Bar adapter to install Lefty forks on standard frames, the Vinyl rotors… all those products proved a real struggle to find metal workshops to be contracted to manufacture them. There were shops that simply weren’t up to the task, others would only do it if they were ordered in thousands of units, sometimes we got to a deal and arranged a deadline, and when the day came there was nothing done. So we are just making very limited editions for frame builders that can order and wait at least 3 months. Those are the runs we can reliably manage.

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BCB’s “Vinyl” Rotors

We always wanted to keep the production in Europe. Nothing against Asia, it’s just that the market has enough stuff that’s made there, wonderful stuff most of the time, but we wanted to offer something different. Apart from that, contracting in Asia is only realistic if you are willing to order, again, a large amount of units,  go there to make sure they’re doing exactly what you want them to do, etc… that is money, quite an amount of money, and BlackCatBone has been a self funded company from the start. We’re just two people, Gerard and me, with limited amounts of money to be thrown into this business, and we have suffered from the lack of venture capital available in southern Europe.

Would we have found investors or venture capital, we could have established a larger company, as that was planned from the beginning, but it simply never happened. That’s why by now we have decided to keep it small and only be an engineering company, but not selling products.

Bikerumor: It seems like you two have had your hands in all kinds of projects? Is there a focus to what you are trying to do, or are you just tinkerers that love bikes and work on anything that catches your attention?

BlackCatBone: That’s a very good question! If we had to define ourselves, both of us are cyclists and engineers. Both of us have been riding bikes since late 80’s. How could we not have our say about every single part of the bike?

In case we had found the funds needed to form a company that offered products on the market, we would have focused on parts like forks, frames, hubs and cranks. That was the plan. Apart from that, we wanted to put part of the benefits on the electronic shifting project, which is internally called “Rollìa”. That is a completely different beast, as we’re talking here about something that involves hundreds of different parts that have to be developed, tested and manufactured. The Lucy fork was a 7 part kit whereas the current state of the Rollìa rear derailleur alone has 84 parts. Rollìa needs some $150,000 to be market ready at least. So that was a project we wanted to work on but always considering that it was to be a much larger business in case someone wanted to give it a try.

In the meantime, we used the different prototypes we were testing to dress our own bikes, and that’s why sometimes things like the e-Grip or the di2 hack we are using as a test bench leaked.

Talking about leaks, it was very funny when we were using a hacked Campagnolo Super Record drivetrain, so 11 cogs, on mountain bikes with a single chainring and some months later the first Sram XX1 leaks appeared in BikeRumor and other media. There were lots of people emailing us, warning that Sram was “copying us”.

All that happened is that when you have a certain level of understanding of how bikes work and, more important, how people use them, you find ways of improving them, and those conclusions can arise at the same time in different places.

We think bikes are so refined today that evolution will come not from the improvement of a single component as happened in the past (i.e. suspension forks, disc brakes) but from concepts that will involve different parts of the bike at the same time. Sram XX1 is a good example as an 11th cog allows a bigger cog spread, that makes possible getting rid of the front derailleur, and that allows a different rear derailleur design and has consequences in suspension design. That’s how improvement will be made from now on. Wheel size is another example since it changes the way the whole frame, suspensions included, work, and thus the whole bike has to be developed again.

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David’s early test bike, a Yeti equipped with electric drivetrain and suspension control

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Bikerumor: How did you get started in electronic shifting and suspension control?

BlackCatBone: Well, this is going to be a long one… I hope it’s easy to read. It all started back in 2009. At BlackCatBone, the company I was running with my mate Gerard. We were testing prototypes of what was to be our Lucy fork, the 12 Bar head adapter and the Rolling Stones hubs. I was racing marathon above all, and ran a M970 series XTR and sometimes a 2006 RockShox SID W/ lockout at the bars.

Bottom line is I was fed up of RD misalignment (XTR M970) and lockout with no remote on the frame (K2 Razorback Team) I had raced Marathon al the season and was planning using my ’07 Yeti 575 a bit more next season. The Yeti needed some upgrades. What to do? I decided to try to tackle the issue of ghostshifting and lots of suspension control which weren’t accessible on the fly, all in one go.

So I decided to build an electronic shifting and suspension control. As I wanted the system to go quickly from draft to prototype, I used RC servos. First day of field test was just a servo tester as shifter!

The system is as seen on Youtube. There were up to 5 servos which were RD, FD, Slow Compression, Lockout and TALAS. All of them had a control on the bars. Shift worked as usual, on button for upshifts, one for downshifts, both front and rear. Then on the left hand you had the TALAS trigger, one push changed the ride height. On the right hand there was a jog that controlled the slow compression setting and a trigger for the lockout.

Soon, I built a pressure sensor on the left brake lever that actuated the slow compression according to a preset, so once a certain amount of push was detected, the slow compression port was increasingly closed thus creating an anti-dive effect that was much needed on the FOX 32 150 RLC fork. This was July 2010, and the system, being just a roughly assembled prototype was proving strong and reliable, so much that I travelled to Canada and the States for a month without any issues in spite of the flight. That was when we decided perhaps it made sense to include among the things to be developed at BCB. We did so under the internal code “Rollìa”. Very soon we had a whole system modeled in 3D.

One of the things we were developing was the e-Grip, the rotating shifter that was seen on the video you published at BikeRumor. Then was when we started using the Shimano Di2 system as a mule, so we didn’t need to prototype a lot of different things at a time but we had a reliable test bench on which to plug the different stuff.

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NOX Parts ready to be assembled into a bike.

On to next year, 2011. I was planning to race some enduro events, so a new rig was needed. -then the Nox 6.5 FR with modified Dura Ace Di2 was built. It meant we were no longer using our own derailleurs, but this time the idea was racing above all, so I preferred not to take risks.

David's NOX

Furthermore, it was clear then that trying to make it to the market with something based on parallelogram derailleurs was going to need an approval or license from Campagnolo, as their patents from 1999 and 2000 covered all the possible configurations of such a system. The mods on the Shimano system were shifters, wiring and rear derailleur.

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Shifters, I did my own using APEM’s switches, waterproof and very reliable. During the season I have tested various configurations, from buttons to microlevers, to e-grips.

Wiring, bottom line is I got rid of the Junction under the bottom bracket, adapted the shifters soldering  them to the wiring and added extra external protection in the most exposed areas as the rear derailleur’s bend. Routing was internal in the right chainstay, and this year is fully internal.

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Rear derailleur: Obviously, a stock Dura Ace is not the best suited derailleur for an enduro rig no matter how many chain control devices you’re using. So first thing to do was using a stiffer spring around the attach bolt. Then we had the capacity issue. Standard Dura Ace is rated to a maximum of 28T cog. To reach a 36T sprocket I made a carbon fiber pulley cage with a larger upper pulley to pivot offset. While we were at it we made the pivot thinner so we could install a one way clutch bearing adding further chain control. This bike has been used in different enduro races in Frances, Spain and this year in the first race of the EWS at Punta Ala, Italy.

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Electronics = no more parallelograms?

But the work only continues. We’re moving on from parallelogram derailleurs onto something radical that really takes advantage of the nature of an electronic system. We already have a model ready for prototyping of a radically new rear derailleur that is patent pending, and are looking for a financial or technological partner that allows us to build a prototype run of between 5 and 10 units to be race proven.

Rollía Box
Potential Rollía Control Box

Bikerumor: What is your/Gerard’s backgrounds that allowed you to jump into designing your own electronic drivetrains?

BlackCatBone: Gerard is a mechanical engineer and I am specialized in vehicle engineering. Mechatronics is one of the hot issues these days in both fields. We have a basic understanding of electronics, but we’re far from being experts on the matter.

Anyway, you don’t need to build your own electronic control unit these days. There are different programmable boards out there that allow people with basic knowledge like us to integrate an electronic control into almost any system. Take Arduino for example. You simply buy a board that has the number of ports you need and, when properly programmed, it can control motors, sensors, input buttons, displays…

That has been our approach to date. If someday a system like Rollìa goes to the market, you can always make the decision of keeping it open source so people can hack it very easily, or you can just design your own proprietary board with a processor that runs your code.

It has always been one of the possibilities we have considered to make the system open source.  Just imagine what would happen if we published the drawings of the different mechanical parts. I’m sure there would be people willing and able to machine the parts themselves, then others would program the boards… throw in 3D printers, we would be talking of a real revolution! The problem is most bicycle users still see electronics like something that doesn’t belong to the bicycle world. Would that change, and I think it will, with enough people interested on the matter it would be a way of taking Rollìa into the real world.


BCB VanVan Concept

Bikerumor: Is electronic suspension control something you’re no longer working on? The brake lever actuated anti-fork dive seemed like a really cool idea.

BlackCatBone: Rollìa has always been a project that combined shifting and suspension control. Once you have a battery and an electronic control on board, the interesting thing is to use it to control all those things that electronics can control more efficiently than a mechanical system.

There are two reasons why I’m not running electronic suspension control on my Nox: Counterintuitive as it seems, one is the mechanical part of the electronic suspension control is pretty straightforward. Instead of manual knobs, there are small servos integrated into the fork and rear shock. Compared to how complex and exposed the derailleurs are, it is a simpler problem so we rather have focused on the development of the shifting system.

The second reason is keeping everything as simple as possible considering I am the engineer, the mechanic, the rider… If there are too many things that can fail when you travel to a race it’s very likely you won’t finish most of them, more when everything is in prototype stage. So we have focused on developing the shifting part of the system as we feel we have a better grasp on the suspension thing.

In my opinion, electronic suspension control will change the way MTBs are designed. Take anti squat for instance: These days many manufacturers are opting for rear suspension kinematics involving an anti squat rate above 100%. I won’t get deep into the matter, but basically there’s no way you can do so without some pedal kickback, furthermore anti squat and pedal kickback tend to be tightly related and the ways of making them independent are not easy to implement on a bicycle.

BCB VanVan Concept

The reason why frame manufacturers are doing this is because like that you can run one setup for everything from climbing to pure downhill, instead of having to flick a lock or propedal lever. Turning knobs and levers is alright either if you’re riding relaxed or when there’s a clear frontier between “uphill” and “downhill”. But that doesn’t happen for instance in an enduro race in which the clock is ticking and suddenly there are climbs to be sprinted in which you need a different setup in the middle of a trail where taking your hand off of the bar is not an option.

The answer these days is more anti squat, so more pedal kickback. Call it what you want, a suspension that is less active the more you mash the pedals.

With electronics you could take another approach: 0% pedal kick back. It would be the electronic control which would adapt the compression settings to the conditions: Type of terrain you’re riding on (measured by both an encoder and a knock sensor on the fork and shock) and pedal torque (a chain tension sensor on the chain tensioner). You could program your own settings; you could even override the system on the go with a button on the handlebar…

It happened with cars, it happened with motorbikes, it will happen with bicycles. Mechatronics change the way chassis are developed.

Bikerumor: You mention you are looking for financial backers on your new drivetrain project, how should someone get a hold of you if they are interested?

BlackCatBone: By now, my email account dxvxkx@gmail is the shortest way. We’re working on a new blog in which we’ll publish the stuff we’re working on and will provide further detail.

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Bikerumor: Anything Else?

BlackCatBone: Sure! We didn’t want to give up on frame design. The customers that bought Ramblin’ & Tumblin’ frames are very satisfied and we have our own ideas on the matter. We also have always had our small carbon fiber workshop, so we’re setting up a frame building shop too. We will only build custom made frames for now.

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BCB Sheriff series #1

The first rideable [carbon] unit we’ve built is from what will be the BlackCatBone Sheriff series. It is a road frame that focuses on comfort and handling. This first unit was built for my dad, who uses a 47.5 cm size. The frame has a very long top tube (556 mm) and a very short stem (40mm) making the steering completely different from a traditional road bike.

TopForntGreen SideGreen

We think the only reason why we use long stems on road bikes is because it has always been like that. But if you ask the older frame builders alive in Europe why they will tell you like that they just could fit people with different torso and arm length into the same frame, and more importantly, using the same lug kit. All they needed was a longer or shorter stem. So the top tube length was intended to be complemented with the stem length, and most people fell somewhere between 90 and 120mm. That was about it. Then a long stem was installed in the minds of the people as one of the characteristics of a racing bike.

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You can build a bike that is as responsive and handles better with a shorter stem. A long stem goes against the kinetics of the front end, that’s why you never see a motorbike with a long stem.

Apart from that we will offer the R&T frame (made for short stems from the beginning too), but now full carbon, a CX frame and a couple of full suspension designs. All of them can be customizable as some parts of the frames are molded, and others are made tube to tube. Next year I’ll be racing a BlackCatBone enduro frame.

RD2 FDfront

A thought on electronic shifting. Not sure where it belongs…

Some people think electronics is going too far when it comes to bikes. They say it is complicating things too much. I get the point, but disagree.

If we’re talking about shifting, I think electronics are more useful in MTB than road bikes. Sure, the rougher environment makes it more difficult to implement and that, along with the fact that Campagnolo was the company that has been developing electronic shifting during the last 20 years, resulted in electronic shifting being marketed for road bikes first.

But if you ask which users are happier with electronic shifting, it results that CX riders are the ones that once have gone electronic never want to come back. It simply happens that electronic shifting works exactly the same when there’s mud and when there’s not.

BlackCatBone Bikerumor Tech Speak (20) Punta Ala Racing

It is the same with MTB’s: Last year I have raced enduro all the season with a hacked Dura-Ace Di2, and it simply stays in gear, no matter what. Furthermore, all you have to do to shift is click a button. It is a great difference from displacing a lever in the middle of a rocky technical section as the one in the 2nd stage (“Rock-Oh”) in the EWS Punta Ala race. I loved it there.

Then there’s the front shifting. Suddenly it is the same burden as shifting a rear cog.  I simply can’t ride a mechanical front derailleur these days, it’s XX1 or electronic, nothing else works for me.

But I feel we need a further improvement to make the rear derailleur stronger than ever. An electronic derailleur will always be more expensive, and breaking a rear mech on a MTB is possibility that’s never far from happening. Furthermore, the whole parallelogram thing makes no sense when going electronic. There are simpler layups when is a motor and not a cable that is actuating the mechanism.

That’s the where we are now, and we think we have something many riders would love from XC to DH.

That doesn’t mean all bikes have to be electronic in the future. There are people riding singlespeed these days, there are even fixies out there. Fixies are negating an invention Ernst Sachs patented in 1893!

There will always be pure mechanical bikes. Only if you’re willing to be the fastest guy you’ll need electronics.


  1. Fantastic. This guy is dead on with everything I’ve observed in the industry and the sport. If I had the scratch, I’d be first in line to ride his developments. Lets get a bike rumor ride report of his test mule, and some more reporting on what these guys are up to.

    As always, thanks Zach,

  2. while the nerd in me is super stoked on all this, the cheapskate dirtbag in me thinks that the time and money would be better spent on learning how to properly tune suspension, improve riding form, et al.

    that being said, i’d still love to take a rip on this.

  3. Great article! I must admit that when I saw the first picture of him standing with the Enduro bike, I pushed it aside thinking it was just another Di2 on a mountain bike. However, his take on derailleur design is very refreshing and outside the box. I see a whole lot of potential here.

    As for the whole mechanical vs. electronic, here is a proven fact. A dual-clutch transmission like those found in Porsche and VW will ALWAYS shift faster than a manual. Always, and the result is faster acceleration. Considering that electronic has many, many benefits over mechanical, why keep using cables?

  4. I like just about everything in the article but proper journalistic integrity has been completely disregarded…WTF is David’s & Gerard’s last names?

  5. @Evan- because not everyone wants to switch to a system that is significantly more expensive and less reliable and repairable. These are bikes, not Porshes. Electronic may have it’s benefits but you’re not going to be accelerating any faster because of it. It may get you all excited, but it’s not for a lot of people, and it takes a very narrow view of the cycling world to ask why anyone would continue to use cables.

  6. @docholiday,

    Really? At least form the sentence properly. IE: “WTF are David and Gerard’s last names?” Could you explain how the absence of their surnames undermines any of the content? It’s an oversight, but not exactly a cardinal sin.

  7. “We had emails that SRAM was copying us”

    Ummm yeah. Let’s keep in mind product cycles are planned out typical a year or two in advance minimum. Rumor has it Shimano is 5-7 years out on design internally.

  8. @sevo – sometimes longer. shimano was rumored to be tinkering with 10+ speed gearings back in the 90’s (up to 13 and 14 speed, and a crazy single sided chain to go with it)

  9. I’m sorry but I can’t take any of this seriously. With seats like on that road bike and suspension linkages from the 90’s. The new technology is great and all but pair it with proper tubing and maybe a speedy looking seat not something from the discount bin.

    • @Nick, that bike was built for David’s father. David even admits the parts aren’t the most photogenic, but it’s what his dad likes. Can’t fault him for having a favorite saddle can you?

  10. @Nick: Tubing that Sheriff frame is Columbus XLR8 Carbon. We think is a great tubeset. As Zach says, seat and components are what my father likes. He is 70 now, started racing when he was 16, so he has had plenty of time to develop his very own opinions. I must admit I disagree with some o»f them 🙂 , but he rides some 600+ km every week, so it seems to work for him!

    About the linkages on the VanVan project, it’s true that it can be considered a Lawwill system, but there ate a couple of details that make it work in a different way to a Schwinn or a Yeti from 15 years ago. First, the relation between the lenghts of the upper and lower links. That makes for a different IC migration. Then, there’s something round on the drawings that changes the way everything works.I am talking too much now :).

    Furthermore, each drawing shows a different configuration: one has linkages to create some decrease on the leverage ratio throughout the travel, thus being more gravity orients, other without those links being more linear but lighter, more to the liking of most enduro racers these days.

    @ColinAG that bike looks terrific! Great job there!

  11. While i agree 100% with the man i think he is a bit late to the party. Lapierre/Rosckshox E:I shox is already that and i think the E:I fork will be out in 1 or 2 year.
    On the rear electronic der why not but i don’t see how it solves the fact that the smaller cog are packed with mud and roots at one point (before that point, my sram X9 shifts just fine).

  12. colin – i certainly remember your project (i’m also an RM regular). but IIRC your project was only servo activated shifting on the gboxx2 (the servo ran the cables to the gboxx). What I am referring to above is having the actual gear changing mechanism inside the transmission be servo actuated.

    That being said, your bike is still my probably all time fav garage build.

  13. I was indifferent until I read about the road bike short stem geometry. A longer top tube with a shorter stem is the fit I need to avoid toe overlap. A shorter top tube with a long stem is why I have that problem. The road bike they made for their father looks cool to me, great job guys.

  14. I really liked everything covered in the article so thanks you. I would really like to see the electronic suspension come to life but we really just need to suck it up and move on from “traditional gear systems” i.e. : derailleur front and rear mech = cant really evolve much further because its been done to death, period. Fine for Road bikes but just messes with MTB frame design way to much no way around it. Chain slap, drop and missed shifts etc all sucks and could be transformed if big companies got behind development. SRAMs XX1 is great and all but in time will be seen as archaic. Go mechatronics

  15. One of these days I will read comments from one of these “BikeRumor Comments” engineers telling me how stupid the designs are and be shocked to find he has actually designed a bike, or built one.

What do you think?