Matt’s V3 disc

Matt’s V3 disc

Matt wanted a fast road bike, and liked the V3 design with a carbon ISP and headtube insert. He also inquired if it would be possible to run all the hoses/wires fully internally. As it happened, FSA had just released their ACR system, which uses a special upper headset bearing, bearing cover and stem to route the front hose directly into the fork steerer. The rear hose and Di2 wire are sent into the headtube, and then travel into the downtube to head to the rear of the bike. A T47 BB shell gives room for the hose and wiring to continue their internal journey all the way to the caliper and derailleurs.

The build kit consists of Shimano Dura-ace Di2 for the shifting and braking, with FSA supplying the crankset, stem and handlebars (plus bottle cages). Zipp NSW wheels with Vittoria tires provide fast rolling.

Paint is by Colorworks, and the final weight came in at 17.5lbs.


  1. Lovely frame and build – amazing work as always.

    Am I right that you got away with a more svelte head tube than is seen on most of the ACR equipped frames by dropping the ACR/ICR assembly into an FSA external cup that uses the same bearing, something like a EC49 or EC44? Not asking you to reveal any trade secrets – was just curious about how this tech could work for bikes that aren’t carbon frames, other than using a much larger head tube than otherwise necessary.

    • Hi,
      I’d also be super interested to hear how you did this as am considering upgrading my custom titanium build to fully integrated, but I can’t fully work out how to do it!
      Any information gladly appreciated.

      • Hi John,

        You need FSA’s headset and stem (and maybe bar, depending on how far you want to keep things internal), a large hole internally from the headtube to the downtube for the hose/wires to route, and a fork setup for the hose to route internally up the inside of the steerer tube.

        Good luck!

        • Thanks Rob. Are you able to answer the question above about how you got the ACR headset to work with a narrower headtube? I am currently using EC44 – is there a way to make it work (it looks as if there is)!!

          • Sorry John, didn’t see the whole thread. FSA offer the ACR system in a EC44/EC44 variant. So you can use it to replace a ZS44/EC44 setup. But it will increase your stack significantly.

          • Sorry – couldn’t click on the reply button below. Thanks so much for the info, I’ll get in touch with FSA as I can’t see the 44 version. Thanks so much for your help!

    • Hi John,
      have you been able to get any info from FSA? Still cant find anything about an EC44 version on the internet except for this article.

      • I’ve found it on fsa’s website, it’s called NO.13/12B/44/ICR, and the sku number is 10100021000010.

  2. Hi Rob,
    Amazing build as usual.

    I was wondering, what fork did you use on this build? Custom? I can’t seem to find any information about a fork that is compatible with the fully internal routing of the FSA system like you have here.


    • Hi John,
      I used a Whisky fork – it was already open internally from the steerer to the blade, so I had Ruckus Composites remove the hose exit at the crown, and made it ready for the internal routing.

  3. Hi all, thanks for the amazing input on the headset. Does anyone know if he’s running a spacer between the stem and the headset? I’m trying to figure the overall stack and I believe the touchup is about 24mm while the stem itself is 30mm (for the clamp) I kinda sized the picture on my screen to measure out that way and it does look like there’s a 5mm spacer in between. Thanks for the help!

  4. Hi, great build! I would like to know the diameter of the seat tube, it seems bigger than 28.6 am I right?

    • Correct, 31.8 on this build.

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