Reader’s Ride(s) – Al’s Custom Fillet-Brazed Fat-bike

Editor’s Note: Al originally sent us a couple photos of his custom built, fillet-brazed fat-bike that has some interesting specs so I asked him to tell us a bit more about it. Well, as you will read, this is not a bike that was just thrown together. The back story is about a guy who has owned several fat-bikes and found the best way to get what he wanted from the fat experience was to do  it himself!

I first demo’d a fatbike in the winter of 2010 – the venerable Surly Pugsley. With BFL’s, little-to-no experience with the subtle-but-significant changes that come from changing PSI, and no other appropriate gear, the experience was mediocre at best. In 2011, I demoed a Mukluk 3. I had more fun this time, and had a couple of great rides on snow, but I was still on the fence – it was a lot to spend on a niche bike – especially one that I was fairly certain I would only ride in the winter months. That next spring, I demoed a Pugsley again to try it out on dirt. The trails we ride here on the front range of Colorado are often full of great chunk and tech throughout, and I confirmed my assumption that, if a fat-bike were to enter the quiver, it would be primarily for snow only and put it out of my mind again for the summer months. The next winter, I realized I had a bunch of extra parts – most of a drivetrain, brakes, stem, handlebars and much of what I would need for a project bike if I could just piece together a frame and some wheels. I started browsing around and stumbled on an awesome deal for a 907 frame (135 rear) with a Carbon White Bros. fork and CK headset. I snagged it up. A month or so later, I stumbled on a set of Rolling Daryls for a great price and I was well on my way. By February of that year, I had this puppy built up (shown with Carver O’Beast):

DSCN0789The bike was awesome. Amazingly stable in snow of all kinds and incredibly capable. It was just what I needed to really get the bug and I drank the Kool-aid hard. I was riding and giggling with the one or two other friends who had picked up fatties at the time, but mostly, I was out in the winter backcountry, on my bike, solo. It was amazing. That next summer, I tried to take the 907 out on the dirt a handful of times – I kept wanting the fat-bike to be more than it was. For my style of riding, however, and the kinds of trails we have, it was just a 30lb rigid bike that was either kinda bouncy or pinch-flatted on jagged rocks. I found the front end too steep and the steering would pull/self-steer a lot with any kind of speed. I hung her up for the summer and, once again, accepted the fate that the fat-bike was a winter-only bike.

In winter of 2012/2013, I rode the heck out of the 907. Two close riding buddies finally picked up fatties and drank the Kool-aid big time. Adventures were abundant. The 907 continued to perform well, but a friend enticed me with a deal on a Fatboy and I couldn’t pass it up. I read about the geometry and the way the bike rode on dirt and thought maybe it could branch the gap to dirt a little better than the 907. Of course, the Fatboy didn’t come in until super late in the season and I only got a couple of snow rides on it, but I liked how it performed in the snow. Equal to the 907, and possibly a little better. I was excited to get it on dirt, but knew it would still be rigid and bouncy. Sure enough, my suspicions were correct. I hung her up for the summer. Then, mid-summer, I came across a Bluto for a great deal and thought I’d give it a shot- still searching for a fatbike that could rock in the dirt and chunk. With the Bluto, the Fatboy did much better than any fatbike I’d ridden on dirt, but the fork was set at 80mm and the head angle was still pretty steep and felt twitchy. The bike still handled great in the snow, however.

Over this period of time, I had also picked up a new hobby and was starting to hone in on a geometry for a fatbike that I thought might get me what I was looking for. With a Paragon 44mm HT, 67.5 degree HTA, 73 degree STA, and a 190 rear end, Ms. Fatbooty began to come to life:



I blew the Bluto out to 120 and changed the damper to an RCT3 and got her built up just in time to get her out on dirt before the snow fell. Eureka! I had found the magic sweet-spot! This bike absolutely slays on dirt. It climbs like a goat and descends like a full suspension rig (I was keeping up with my times on my FS bike). It’s still a 34.5lb hard tail, but floats more than any HT I’ve ever ridden (and I’ve ridden a few).



After a few snowy rides, I’ve also confirmed that she rocks in the white stuff as well.

Thanks for letting me share my story. Yay bikes!

4 Responses to Reader’s Ride(s) – Al’s Custom Fillet-Brazed Fat-bike

  1. Matt Gersib December 29, 2014 at 12:51 pm #

    Very nice work… That looks like a well thought out ride!


  2. Zachary Brown December 29, 2014 at 12:53 pm #

    Beautiful machine. That would be a fun project to take on building my own frame.

  3. JB December 30, 2014 at 9:26 pm #

    Centennial Cone aye? Nice frame!

  4. aaron w January 8, 2015 at 10:04 pm #


    I’ll be watching for you out there(even day chimnex loop..) to pick your brain…

    into the kool-aid,