MYTHOS IXO STEM REVIEW

Review by Robert Johnston | Photography by Ian Linton / Robert Johnston

Manufacturing processes are constantly developing, and while the conventional processes like machining and forging do a fine job for the majority of bicycle components, there are limitations as to the geometry and structure that can be achieved. One of the newer crop of technologies that’s increasing its stake in modern manufacturing is 3D Printing (also known as Additive Manufacturing). Once a technology reserved for prototyping, nowadays the possibilities that 3D Printing offers are being realized for functional components, and thanks to improvements in the machines and processes, components can now be made with a better strength-to-weight ratio than is typically possible with conventional manufacturing methods. Exciting stuff, I think. I’ll preface this review by sharing that my previous job was as a design engineer for the parent company of MYTHOS, Metron. But believe me when I say that I’m more than happy to share with you the negatives as well as the positives of their first mountain bike product, the IXO 3D printed titanium stem (press release here).

THE LAB

The MYTHOS IXO stem is made out of aerospace grade titanium (Ti6Al4V), using an additive manufacturing process called Electron Beam Melting (EBM). This process uses a concentrated beam of electrons to selectively melt titanium powder, stacking up many thin layers (typically between 50 and 100 µm, roughly the thickness of a human hair) to create the selected part. The technology allows for each layer to have the exacting geometry the designer wishes, meaning that complex shapes can be created inside components, where machining operations would be unable to access. Designing to take full advantage of this process then allows engineers to eliminate excess material from where it isn’t needed, minimizing the weight of a component without sacrificing strength or stiffness.

In the case of the MYTHOS IXO stem, the design focus was to place material only in the areas that are subjected to the highest loads during aggressive mountain biking, which in turn boosts the stiffness and led to them obtaining a 16% gain in torsional stiffness and 11% gain in bending stiffness when compared with an equivalent alloy stem. MYTHOS tested the IXO stem to the typical ISO standards used for mountain bike components, alongside testing out on the trails, so you can rest assured it’s strong enough to take the abuse.  MYTHOS opted to go down the no-gap faceplate route at a later date than when my test stem was produced, making installation easier and giving a cleaner look.

The IXO stem is currently offered in a choice of 40mm or 50mm lengths, to fit a 35mm diameter handlebar only. However, MYTHOS offers a 3D Printed titanium adaptor (purchased separately) to allow for 31.8mm handlebars to be used with no loss of stiffness. Buyers can choose whether or not to have alignment marks on the stem at the choice of purchase, giving the option of a cleaner look or easiness of setup. The IXO ships with titanium hardware as standard, has a 38mm stack height on the steerer tube, and tips the scales at 136g all in. The MYTHOS IXO stem will run you £300 plus shipping, or roughly $310 plus shipping and taxes if you’re purchasing it in America. With this you get a 2 year warranty against any defects. So, it’s certainly not cheap to have this 3D Printed Titanium bling leading the charge on your bike, but how does it ride?

THE DIRT

The IXO stem had first been conceptualized when I was still working as an engineer at MYTHOS’s parent company, Metron. In the couple of years since I’ve left, they’ve moved fast in creating their new component brand and bringing their ideas to a reality. I was excited to receive the fruits of their labor, and finally get to ride something that came out of their 3D printer, instead of giving it away to world class athletes.

Knowing the manufacturing process well, and having had countless 3D Printed components come across my desk during my time in that job, I had a pretty good idea of how the MYTHOS stem would look up close and personal. If you take a close look inside the guts of the IXO stem, you may be a little surprised to see a slightly rough looking finish that doesn’t quite exude the quality feeling you may expect from a stem of this price. Unfortunately this is one limitation, or at least consideration that needs to be made with the 3D printing process, and this is after the considerable amount of hand finishing required to take the printed stem and turn it into the finished product that you see. You can take this roughness as character, and rest assured that any irregularities are more than accounted for in the long-time developed design processes that MYTHOS uses for their products. The proof is in the fatigue testing that MYTHOS conducted on numerous stems, during which they all passed with flying colors. 

The IXO stem mounted up to my test bike – a YT IZZO – with a reassuringly tight fit, and all bolted up smoothly. Being able to see through the stem plays with your eyes a little at first, but soon you get used to it and can instead appreciate the intricate design on the inside that’s only made possible thanks to the additive manufacturing process. It’s certainly a head turner, and I was asked about the stem many times throughout the test period. How did it ride? Well, it blended into the background. It’s a stem after all, and not an insanely light one at that. I can’t say I felt the increased stiffness compared to a standard aluminum alloy stem, with the trail conditions loose and the Fox 34 fork not quite in the upper echelons of stiffness itself, but it didn’t cause any issues or make me think about it at any point. In my head, that’s a compliment for a stem – it must be doing its job well if you don’t think about it.

I rode the IXO stem hard, laying down some wattage in some sprints up the Tweed Valley climbs and pulling hard for the trail center gaps that the YT enticed, and never once heard a peep from the MYTHOS stem nor experienced any slipping on the bars or steerer. Under hard riding in wet conditions with the inevitable cleanup missions that follow, it’s not uncommon for a stem to develop a creak before long, but this never manifested for the IXO. The open cavity and complex internal geometry means that once mud gets in there, it takes a bit of effort to get it out. I’m quite against pressure washing bikes, which would undoubtedly shift the mud, but otherwise you may have to resort to getting an (old) toothbrush involved to help shift any build up.

When it came to removing the stem from the bike, the stainless steel bolts fitted to my stem felt slightly sticky, requiring considerably more torque to undo than they were tightened to. This shouldn’t be an issue for customers however, as they are now shipping with titanium hardware instead, which they found to work better as well as shaving some grams. These titanium bolts will be supplied with a coating of copper anti-seize compound to further prevent any issues over the long term, so the IXO should be a set-and-forget piece of jewelry to hang off of the front of a worthy machine. Realistically you’ve got to want to buy into the technology or really like the looks to justify that high price tag – it’s an unfortunate reality of the cost of one of the most advanced manufacturing methods and premium materials. Knowing the passion and expertise that the team behind MYTHOS has, I think we can expect to see lots of exciting products coming out of these guys – this is just the start.

The Wolf’s Last Word

The MYTHOS IXO stem isn’t going to revolutionize your riding experience, it may not even change it at all. However, it performs as well as you could wish any stem to, looks great (subjectively, of course), and is a chance to get your slice of cutting edge design and manufacturing on your machine. 

Price: $310/£250 (plus shipping and taxes)
Website: mythos.bike