Denmark’s Principia just sent over these images of their new Revolution road bike, the first complete bike we’ve seen with thru axles front and rear, built with Dura-Ace Di2 and the just-announced Shimano hydraulic disc brakes.

Principia has been around since 1990, primarily sold in Europe with no current US distribution. The Revolution is a completely new frame for them, and Principia’s Andreas Hagbarth says the layup was designed to “achieve ultimate stiffness with the new axle system” while still offering an all-day comfortable ride.

Besides the new frame, it’s sporting plenty of the newest parts like the new FSA K-Force Light BB386 asymmetric crankset, which drives rolls on custom DT Swiss Revolution wheels designed around the 15mm front and 142×12 rear thru axles.


Up front is a tapered headset holding a custom fork designed for 160mm rotors and post-mount brakes with the DT Swiss 15mm thru axle.


The frame is Di2 ready. Hagbarth says it’ll work with either SRAM or Shimano disc brakes…we’re just not sure what you’d do with a SRAM mechanical drivetrain here.

The wheels were co-developed with DT Swiss using a 38mm disc brake only 700c full carbon rim. They’re laced with Aerolite spokes, and the hubs are based on 240s Classic with some customization to fit the frame and are 11-speed ready.

The complete bike specs:

  • Principia Revolution Frame+Fork
  • DT Swiss Revolution wheelset
  • Shimano Dura-ace Di2 front and rear mech
  • Shimano R785 shifters, brakes
  • Shimano 160/140mm disc rotors
  • FSA K-force Light cockpit and crankset
  • Di2 battery inside seatpost
  • Schwalbe ONE tires
  • Prologo saddle
  • Complete bike weight: 6,8kg (claimed)
  • € 7999

Should be in shops (in Europe) in January 2014.


  1. Thru axles are going to mess up quick wheel changes, I can’t see those catching on at the highest performance levels. Even amateur racers want to be able to get a wheel fast.

  2. The future has arrived… sprinters dream for sure. Hopefully road will get the standards worked out right away for neutral support wheel swaps. Large brands like “S” and “T” will most likely do their own standard… however hopefully they will see customer support benefit for road racing axle standard for wheel swaps. Great to see this finally happening for road bikes (front and rear TA). Good job Principia.

  3. @G-Man, I agree with you that TAs are not quicker than QRs, but they’re pretty necessary on a disc brake frame. Hopefully tires become even more flat-proof negating the need for changing flats anyway. I think they could’ve gone TA without going to a 142mm rear–is 135 too passe as well?

  4. Flats aren’t going away any time soon. There will need to be a TA design that allows for fast wheel changes before any real difference will be allowed in the pro peloton. Or maybe they’ll move entirely to switching bikes , and repair the wheels on the team car. 142 isn’t needed for now, but it certainly won’t hurt with keeping wheels strong, and allowing the space for future gearing improvements. Frames are pretty maxed out at the moment.

  5. @Honeybear: 135×12 are slighter harder to deal with. All 142 does is add a couple 3mm slots in the frame for easier wheel positioning. Same chainline.

  6. @Mindless, sorry, no. I can change a Q/R flat in under 40 seconds, with a new tube. The fastest TA design still takes me that long to get out of the frame. And chill out with the attitude, dude. It isn’t needed here. You can disagree without making it personal.

  7. @zenbike: Sorry, but you clearly did not try some of the new axles, like Manitou’s. TA are faster to setup. Especially on a fork. And 142×12 is faster to set in the frame.

  8. I think in discussions like this, the frame has more to do with the end result than the axle attachment. Sure, without aggressive lawyer tabs a good QR is amazingly fast – just open, and the wheel drops out. The problem with quick releases these days, especially on frames with disc brakes, is that there are massive lawyer tabs that require you to unscrew the QR after it is open – I’ve even come across frames where you ended up having to take the QR nut completely off the skewer to get the wheel out. In the old days you could just file down the lawyer tabs for fast wheel changes, though it’s not so easy with carbon. It is on these later frame that a TA would at least be just as quick, if not faster.

  9. bring it on! the possibility of time is possibly a good trade of when you look at all the variables which many racers/riders on the road will no longer need to worry about. I’ve seen to many carbon frames damaged from rough changes all the time. It is hard to fix and not warranty.

  10. Manitou’s TA design is as quick and easy as (if not more so) any QR out there, would be great if they’d license the design to road forks and create a rear thru axle version.

  11. not needed for everybody. unless you are over 170lbs and can really really hammer standing up, these are just an annoyance.

    i am at semi-pro level, 155lbs, can keep up with almost all sprinters at the line, but my strength is hammering the hills hard. i mean really hard, big gear hard. ok you get the idea.

    i cannot feel a difference in the two axle types. what i can feel is the wheel flexing, cranks flexing, some rear triangle flexing, even the tire getting some bounce. but the axle? no. no way.

    just another must have for the keep up with the pro’s money spenders. unless you are 220lbs and up then this will not make much of a difference. and if you are over 220lbs most of your bike parts are going to be flexing.

  12. @askar: The big stiffness benefit isn’t just the axle in isolation. Remember that, by connecting the dropouts at the front and rear with short, stiff axles that are integrated into the frame, you are stiffening up the fork and the rear triangle in a big way. I’m not a big guy, but I can definitely feel differences in stiffness between different bikes. I’ve never had a chance to A-B identical bikes with TA and QR rear ends back to back (I guess some Yetis and other bikes can do this), but I have ridden otherwise identical QR and 15mm TA 32mm forks from Fox, Rockshox and X-Fusion and the TA forks were shockingly stiffer every time. Not even close.

    Though it’s obviously silly to assume that axle flex is detrimental to most of our riding, rear triangle flex (as you say) and fork flex are pretty noticeable. Bracing the fork and rear triangle with a TA will keep those more under control, for sure.

  13. I’m with Max on 15mm thru axle benefit. Night and day difference between same year SID forks with and without the screw axle. Using an identical appropriate front wheel, I could immediately ride ruts confidently that were sketchy with the QR. Don’t know how much difference it will make on pavement though.

  14. There is no revolution. Principia is not the only one to come with this axle. BMC Racing have three models in there new 2014 Grand Fondo program, with the same setup and also discbrakes.

    After Principia closed down there factory in Denmark they are just another FAR EAST brand. Nothing new and nothing revolutionary. Back in the 80 -90 the brand was state of the art in producing aluminium frames.

  15. Disc brakes…check
    Front thru axle… check
    Rear 142 x 12 thru axle… check

    This bike has all the checks. The future is now.

  16. Brakes: there are two changes being made here:

    1. Hydraulic
    2. Disc

    Hydraulic is great, cables belong in the museum, but discs on a roadie? My 16 year old hydraulic magura rim brakes are superior in feel, control, and power to any hydraulic disc brake I’ve used or owned. A rim can be seen as a large disc, allowing much lower braking forces to be applied to the frame and wheel. IMHO that is more important on a racing bike than moving wear from the rim surface to a disc.

    Bring on the hydraulic rim brakes SRAM & Shimano!

  17. Nice point @andynoakes. Those hydraulic rim brakes are still a very sweet product, though I’ve never seen or heard of them on a racer till now.
    And, in the context of off-road riding and fork flex, I always had the impression that a bit of lateral flex between the two sides of a fork helped the front wheel keep a little more perpendicular to the ground in corners (with bumps esp) and that this meant the tyre had to do a little less work maintaining traction. ie: I’m not convinced stiffness is the be-all&end-all some seem to think. Maybe it’s just something engineers are getting better at that they want to sell us!

  18. Yes, a million times yes! The new gen axle are so freakn fast to take off the wheel. Turn counter clockwise, pullout and boom!

  19. Here is where the future standard lies for road cycling:

    Thru Axles: 15/100mm front and 12/142mm rear
    HYDRAULIC disc brakes (mechanical DB are just a temporary ‘bridge’)

    The removal of a wheel with a thru axle is not a biggie for neither the common rider nor hard core enthusiast. The DB forces essentially require them, as MTB as found. The benefits are huge and numerous regarding ‘ride’ but it also makes wheel alignment foolproof as 142mm are self centering; yet have the same flange spacing, chainline, bearing placement, etc. of 10/135mm QR.

    Once all the frame and fork manufacturers start incorporating this change or at least offering as an option (see Yeti convertible axle systems), every reputable hub/wheel manufacturers will certainly accommodate. And, with these particular thru axle sizes, hub makers can offer different end caps so people can choose the antiquated QR connection if that’s what the have or prefer.

    What will motivate the frame/fork manufacturers to get going on this eventual TA revelation? You and me, the consumers, that’s who!

    What will motivate the UCI to finally make the switch for the pros (as it rightfully should)? In my opinion, here is your answer:

    The Focus Rapid Axle Technology (RAT)

    You heard it here.

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