After many years and many challenging projects, it is only fitting that our 350th custom frame would be something special and unusual. Since we began designing bikes with the Pinion Gearbox in 2012 we have always thought a fat-bike would be the perfect application.    Frozen derailleurs, slow unresponsive shifting and finishing a mid February ride in one gear always led us back to discussing the Pinion Gearbox as an alternative.  The folks at Pinion obviously heard our calls (and the desire to jump into the growing fat-bike segment didn’t hurt) and now produce a specially offset fatbike crankset and chainring spider allowing us to create the custom O’Beast you see below…

Pinion Gearbox Fatbike by Carver

The Ti O’Beast was the obvious choice for our first gearbox equipped fatbike.   Having previously built Ti 420’s  gave us a leg up with an already proven titanium mounting plate, allowing us to work with our builders and integrate the mount into our current Ti O’Beast frame.

Pinion Gearbox Fatbike Crank

For our first Pinion equipped fatbike we chose the P1.9XR transmission. The P1.9XR is the lightest transmission Pinion produces at 2200grams and features 9 real gears and a 568% overall gear ratio. More than enough to range to tackle the toughest New England singletrack.  Pinion also offers a narrow ratio 9 speed, a 12 speed, and even an 18 speed version, If you find you need to make some tweaks as you head into winter you can always play with chainring / cog combinations to find the sweet spot for your riding style.

Pinion Gearbox Fatbike by Carver

This custom O’Beast was built for a customer with all the latest Carver Bikes parts including our new Carbon Fatbike rims, Carbo’Beast tapered fork and the very popular Carver MyTi Carbon handlebar.

Using a Pinion transmission mounting plate gives us plenty of room to create chainstay clearance for the Dillinger 4 tires used in this build.   The chainline also worked out perfectly thanks to the new offset chainring spider and with a fixed chainline you will never have to worry about the chain catching the tire.

One of the coolest aspects of Pinion equipped bikes is that they use a simple single speed rear wheel. That means that you can use a single bike with a huge variety of different wheelsets. From Fat Bike to 700 x 23 road bike in the time it takes to do a Tour de France wheel swap. A true Swiss Army bike.

Pinion Gearbox Ti Fatbike by Carver Pinion Gearbox Fatbike by Carver

  • Vauban

    Beautiful Bike Davis!!

  • mikeetheviking

    Oh dear Lord! What a bike!

  • Have you built a version of this bike with a belt drive?

    • Forrest Carver


    • Fraser Cunningham
      • Amazing beast!
        What’s the bike cost?

        • Fraser Cunningham

          Kevin, as it is in the picture I have $6250 invested, $7000 including the set of ‘thin’ wheels, as the primary use is commuting. Those costs are based on my doing the wheelbuilding work, and scavenging some of the parts and building the bike myself.

      • newtonrj

        What the ‘fork’ is that? Love the bike. Thanx for sharing. -RJ

        • Fraser Cunningham

          RJ, HAHA! That truss fork was also made by Davis’ team, I spec’d that because the primary use for this bike is commuting, in all weathers. Corrosion resistance and ruggedness are primary requirements, and I also just loved the aesthetic of that design. Turns out (pun!) that the fork is quite compliant too, even more so than the early generation Carver carbon fork I had on my Moonlander prior to building this rig.

          • newtonrj

            Very excited. Have been planning a Carver Ti Obeast build for over a year. Now underway. Like yours it will have belt drive but instead of Pinion crank, the build will have a Rohloff rear hub. Fork is the Carbon Obeast. I’ll post a pic once it gets shipped and sized in. -RJ

          • Fraser Cunningham

            Nice! I really like the belt drive, near zero maintenance even in the nasty winter weather. I decided on the Pinion so that I can do easy/fast wheel swaps, to accommodate weather changes, not so easy with a hub gear (which I had on my previous commuter). I have a wheelset with 100mm rims shod with Surly Lou’s, and the other set has 24mm rims currently shod with Schwalbe Ice Spiker Pro tires. In the summer the ‘skinny’ wheels wear Schwalbe Marathon tires with Slime inner tubes, for high mileage and puncture immunity.
            I now have over 2,200 miles on my O’Beast, and it is just awesome!

  • Christian Zerafa

    What does it mean when you say “specially offset fatbike crankset and chainring spider”.?
    Does it mean that the Q factor is wider on the drive side?
    Like one has to ride it with one leg further away from the centre of the bike than the other leg?