Foe's Racing Aluminum SheetsEvery bike begins here, with a water jet cut piece of aluminum

At a time when the cutting edge of mountain bike suspension technology features 2″ of supple elastomer based travel, Foes Racing was pioneering long travel suspension and helping push the limits of the downhill race scene. Leaving other companies to argue over the benefits of suspending the rider or the bike, Brent Foes helped push forward innovations by experimenting with the little understood field of suspension, and creating the distant ancestors of today’s modern “Enduro” bike.

Over twenty years later, Foes Racing continues to push the envelope. With suspension technology having finally caught up to the vision and capabilities of the bikes they’re paired with, the company can now focus on continuing the legacy of building burly aggressive aluminum frames for which they rose to prominence.

During a recent trip to Southern California, we had the privilege of stopping by the Foes Racing Factory in Pasadena to get a closer look at how these legendary frames are created from flat sheets of aluminum.

Foes Racing Hydroforming ProcessThe aluminum top tubes are formed into distinct shapes by a fifty ton press. The process involves placing the precut sheets onto dies, which are left and right specific. Brent constructs the original prototype dies from wood, but they can only survive maybe a dozen uses. Once they’ve finalized the design, they create aluminum forms.

This press was built in 1953 for aerospace manufacturer Lockheed Martin, but has since been converted for bicycle manufacturing. One of the advantages of this system is that different durometer pads can be substituted to alter shapes.
Foes Racing Stages of Hydroforming

From top to  bottom: Precut aluminum sheets, the final mold constructed by Brent, half a hydroformed top tube, and a tack welded top tube.

Hydroformed Foe's tubes waiting to be tack welded

The downtubes are hydroformed at a separate local facility.Foe's Racing Frame Jig

Brent builds a jig for every model. Foes Racing Aluminum Frame Jigs

The aluminum dies used to produce every model (both current and historic) are stored throughout the factory.

Foe's Racing Headtubes

Half the shop floor is dedicated to raw materials, partially constructed frames, and Brent’s welding station, while the other half houses American made Haas CNC machines.  Headtubes, linkages, and everything in between are formed here from raw materials.

In addition to manufacturing bicycles, Foes also produces an assortment of things for movie studios, which we’ll cover in Part 2 of our Factory Tour coverage.

Brent Foe's Working on frame AlignmentEach frame is then assembled and locked down in place on a welding jig.

Foe's Racing Frame Ready to Tack

Now that the various components have begun to take the shape of a bicycle, they are welded by Brent.
Brent Foes Finished Product

When we were at the Factory earlier this year, we heard rumors that the Brent was considering doing some  customized frame geometries for customers. Interested? Let them know in the comments

From afar, you might be tempted to assume that Foes racing is like any large production facility, but seeing the process up close gives you a very different insight into the process. Each frame is hand welded by Brent and the production batches are fairly small. For any given initial model run, they only make something like 10 frames per size.

Buying a Foes Racing frame is akin to purchasing a custom bike from an artisan builder. Not only is the craftsmanship incredible, but you also get the feeling that the bikes are built to last until long past the next big trend in mountain biking.

Curnutt Shock RoomThe Foes Factory consists of two buildings. One which houses the majority of the CNC machines and welding fixtures and the other where frame assembly takes place.

As we were saying our goodbye to the employees in the main CNC area and walking out towards the second building, we passed by a dark room that when lit revealed a full suspension assembly room. It may have only been presented to us as an afterthought during our tour, but a few years ago this was home base for the Foes in house suspension products.

Curnutt Air ShockWhile the company no longer really manufacturers Curnutt forks or shocks, they still have all of the tools on hand to work on them.

Foes Assembly Area and FramesThe neon monster green paint scheme on the right is a new custom color scheme they are now offering

Across the driveway there is a separate building which houses a 50 ton press, an assortment of metal working machines, a spare pit bike or two, and frames waiting to be assembled.

After Brent welds a batch of frames, they are sent to a local heat treatment facility. This is a two step process. In the first half, frames are heated and then put in a freezer to halt the hardening process. Then Foes employees hand check each frame to ensure there are no alignment issues, then the frame goes back into the oven for a second round of heat treatment.

Foes Assembly Area

After the final heat treatment, the frames arrive back at the Factory, where they receive another round of QC tests.

At the moment, Foes bikes are only available as a frame only option, but the company has plenty of fancy bits laying around to build up prototypes rigs, etc…
Foes Racing Guard Dog

And for making it this far, here’s Ruby, the Foes Racing Mascot

Stay tuned for Part Two of our Foes Racing Factory Tour, where we’ll explore some of the awesome projects Brent has floating around the office.

Foes Racing


  1. K11 on

    great article. (i had to remove the remainder of my comment, involving china carbon rim articles, because…well, my comment was removed)

  2. Devin on

    Awesome, I’ve always loved Foes bikes. Can’t wait to see the progress on his negative travel prototype. Keep up the good work Brent!

  3. Roy on

    It’s great to see the smaller side of US bike manufacturing. Ventana, Foes uhhhh, I don’t think there are any others left. Intense still makes alloy in house but no doubt 5 Made in China carbon models are having a massive impact on the bottom line, so hardly one of the smallest anymore. Brent has long made some of the best looking most well thought out purposeful designs in our sport. Chapeau!

  4. NCMTB on

    Brent how about some XLs, instead of the custom geo? I have always wanted a bike from you, but being 6’4″ they are just too small for me so I have went with Turner, Ventana and Lenz instead over the years. Really wanting a longer travel 27.5 and the FXR275 looks mean. Great article and love to see the US bike manufactures shops.

  5. CXisfun on

    Really cool video of hydroforming. I had no idea HYDROforming could be done without fluid of some sort, totally wild! Great reporting Bikerumor!

  6. django on

    @Alex – Thank you. You are killing it! I came here to say the same thing but it seems ample folks know what mechanical forming is.

    BikeRumor – Please stop. People are confused enough. You don’t have to add to it. Just. I mean. C’mon. Please?

  7. Al Boneta on

    The reason you didn’t see any Hyrdoforming in the pictures is because “The downtubes are hydra-formed at a separate local facility.”

  8. Psi Squared on

    At least Al Boneta was able to read the article with comprehension. Granted, the video title could use correcting, but it’s nothing that I’d get my panties knotted over. I guess the people put out by the error could ask for a refund on their subscription.

  9. CXisfun on

    “How Foes Racing Hydroforms their tubesets” is the title of the video, with nary a second of hydroforming shown. They may as well have titled the video “How Foes Racing likes dancing cat videos.”

  10. Antipodean_G on

    As @django said, there are plenty here who know what’s wrong with the terminology used and the ensuing confusion.

    For those that don’t…

    Mechanical forming (pressing, rolling swaging whatever), is when a blank sheet, or tube (in the case of swaging) is mechanically manipulated to become another shape. The mentioned “fifty ton press” in this case forms the two halves of the top tube, which are then welded together to form what is often referred to as a monocoque form; though in this case it’s just a fancy TT.

    Hydroforming is when a tube is placed into a die (aka tool) and fluid, usually an oil of some sort, is injected into the internal cavity of the tube under pressure. This process pressure forms the ‘blank’ tube to the shape of the die.

    The upside of hydroforming vs. say pressing, is that you can butt the tube prior and end up with a fully butted, formed, fancy thing that makes engineers happy and the consumer go ‘ohh, ahh, fancy shape’. The down side is that the tooling is expensive, so companies now say ‘let’s trump for carbon tooling instead….’. But that’s another story… 🙂


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