Inviscid Design Speedfil R3 – Review

“One size fits all” usually doesn’t work quite as intended. However, it’s usually not because the products don’t deliver, but instead because there are always those situations that require a solution that is a bit outside the norm of the “one size fits all” standards. For those times, you need solutions that are highly specialized, or so highly adjustable, that they can meet the needs of even the most unique circumstances. The Inviscid Design Speedfil R3 definitely can claim the latter–for when your needs go beyond the abilities of a fixed rear wing.



The R3 is designed from the ground up to be the most adjustable and adaptable rear hydration system available. Want a single-cage mounted up tight against the saddle? The R3 has you covered. What about a dual-cage setup with integrated storage for CO2? The R3 can do that, too. Or how about a setup where the cages are mounted both vertically and high up against your back? Yes, the R3 can handle it.


The R3 is based around a dual pivot arm that allows you to place the cage(s) wherever you need them. Whether you are looking to mount the cages high or low, the arm can accommodate. More importantly, when you consider that many saddles today come with built in transition hooks that prevent most hydration solutions from fitting, the arm of the R3 can easily adapt.


Included with the R3 is a pair of cage mounting options. The first option is a simple, single-cage mount. The other option is a combination mount that is both the cage attachment point and the home for a pair of CO2 cages, an inflator, and built-in Velcro straps. The mount allows you to choose between going with a pair of cages or sticking with a single cage. One of the best features is that switching between the two cage mounts is extremely easy—simply remove a single bolt and swap the mounts. With the R3, you can have both a training mount with backup supplies and extra fuel, as well as a race mount with the minimal needed items.

Ride Impressions

We rode with the R3 in three configurations–single bottle mount, dual bottle mount with one cage, and dual bottle mounts with a pair of cages. We mounted the R3 to a Dash Cycles TT.7, Adamo Podium, and Cobb Fifty Five. Between these combinations we were able to test the R3 with saddles with and without transition hooks, as well as titanium rails versus carbon.


The R3 is as adjustable as advertised. For saddles where the rails go all the way back, we could easily fold the arm in to get the cage where we wanted it. More importantly, for saddles where the rails end early (such as on the Fifty Five) we were able to stretch the arm out and get a very useable position for the cage. This is becoming more useful as more companies release saddles with short rails meant to make use of built-in proprietary cage mounts (the Sitero, Tritone, and Fifty Five come to mind), the R3 allows you to use a common solution for all three.


On most of our rides we used the dual bottle mount with either a single or dual cage attached. This allowed us to also ride with a pair of CO2 cartridges to the mount along with a small bag using the built-in Velcro straps. When riding with a pair of cages, we found the mount to work exactly as advertised. Everything we wanted to carry was held secure and within easy reach. Our only difficulty was when we chose to use the dual mount with a single bottle. This resulted in a very long solution that tended to bounce both vertically and horizontally. Our training partners voiced frequent comments regarding our dancing hydration mount, which mostly revolved around the very real concern of a launched bottle. In our opinion, all of the weight at the end of the plastic was simply too much. Our advice: go with the single mount or use two cages with the dual mount.


The other concern we had was how the R3 attaches to the saddle. The R3 makes use of a sandwich solution where the saddle rails are placed between two pieces of plastic that are then tightened. Unfortunately we have found that this design (a design that is used by many companies) tends to not be as secure as other cage mount solutions. For instance, if it’s not tightened all the way it can easily loosen and dislodge. We had a particular issue with carbon rails. And no amount of carbon paste could prevent the R3 from sliding a little.

Final Thoughts

The R3 works exactly as advertised. It’s a highly adjustable solution that allows you to bring your choice of hydration on any ride. If you have a need that goes beyond the standard, or just want to switch from training setup to a race setup with a single bolt–take a long look at the R3.

12 responses to “Inviscid Design Speedfil R3 – Review

  1. This is not speedfil design , I believe they bought over the design from BG racing. I have been using this design for almost 2 years before speedfil launch

    • The SpeedFil and the Beaker Concepts solution are now one and the same. The BC Blaze is a great design that SpeedFil has made some enhancements to and both are now selling.

  2. Alvin – You are correct, almost! We,Inviscid Design, acquired the rights to the design from our friends at Beaker Concepts. We enhanced the design/engineering of the existing product and introduced an additional single mount not previously available NOR as a 2-for-1 mount in a single package. The result Speedfil R3 can deliver more performance than most other rear carrier systems on the market.

    Thanks for your comments and to the “Geeks” for this great review!

    Inviscid Design, Inc. – Speedfil

    • David,
      I have read that when the R3 was previously the Blaze under Beaker Concepts, the plastic portion that clamped to the saddle flexed upon tightening (which was supposedly how it was supposed to be and also required to minimize any dislodging).

      Can you comment if there were any large upgrades to the hardware portion of the R3 that mounts to the saddle rails? I’m a bit apprehensive of having non-metal clamps which may not be as strong.

      Thanks again!
      Great review as always Aerogeeks.

      • Hi Terry,

        We actually had the same concern with the R3. On one of our rides we did see slippage and lost a bottle (found we had more room to tighten down afterwards).

        We found the clamp worked best on saddles that did not have a large amount of room for the clamp to slip up and down on. BTW this issue isn’t limited to the R3, we have seen similar issues with other companies that use the “sandwich” clamp design.

        Hopefully this helps answer the question.

        • Thanks Aerogeeks. That is helpful information.

          Do you happen to know if the clamp hardware was upgraded at all perhaps to a harder plastic or even metal clamps?

          Did you have the seat post clamp “flexing” after tightening it up enough so it would not slip?


      • Sorry about the delay. We reached out to Inviscid, they just got back to us and let us know that the current version has no updates but future versions may as they experiment with new materials.

      • Thanks! I dropped them a message as due to the position of my seat (pretty far forward) there isn’t enough room to attach the clamp. If I don’t hear from them soon I might just try the blaze clamp and see if it works.

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