People like puzzles. I was addicted to the NY Times daily crossword for years. I got cured when I moved to the middle of nowhere, beyond the reach of any paper that carried that damned crossword.
One puzzle triathletes are both intrigued in and bedeviled by is the puzzle of bike fit. We've got dozens of articles on bike fit archived here on Slowtwitch, and that's the problem. It would be much easier navigating your way around if there were only one or two.
Where to start? Which one should you read first, and what's the progression? Which pertain to you? Which should you skip? What you're reading here is an attempt to wrest order out of the confusion — to simply whelm you (lest you be overwhelmed). Hence, this is the "Tour de Bike Fit," that is to say, your guided tour of the Bike Fit section of Slowtwitch.
One thing you should know first and foremost, I suppose, is that there's a history and a pedigree at play here. The author writing to you now (me) is generally credited with designing and building the first tri bike. My "aha moment" occurred in 1988 and after two decades I obviously have a lot emotionally and financially invested in the idea. Forewarned is forearmed: You should consider how that might color and bias everything that comes hereafter. Steel yourself for a pitcher of the Slowtwitch KoolAid.
About that historical narrative: a bit of that was recounted here, in the logical starting point in our bike fit section. In this article we ask you to ask yourself what sort of rider you are. Should you pursue a road race bike (and position) for racing triathlons? Or, are you a good candidate for a tri bike?
Before you get into the tall weeds of X/Y coordinate systems and steering levers, I recommend you inoculate against the ear ticklers that hang around tri bike world like remoras. For many triathletes — pro and AGer alike — the best thing they ever read or heard is the most recent thing they've read or heard. But it's hard to avoid this foolish behavior if you're not conceptually grounded. To that end, and to help you parse between sound and systematic thinking versus the fad of the moment, we present an inoculant in the form of an article.
If you're a confirmed puzzler, you'll want to delve further into the subject of bike fit. But you might want to avail yourself of a primer on the subject, to familiarize yourself with basic fit and geometry terminology. If this article appealed to you, then you may want to read a deeper discussion specific to a tri bike's steering geometry.
If you're ready to embark on a quest for your perfect tri bike, what should you look for? Are you a good match for a Scott Plasma II, or a Kuota Kueen K, a Kestrel Airfoil or something offered by Javelin or Felt? A bit of that nuts and bolts breakdown is covered here. This article will give you your first inkling about how tri bikes differ one from another.
Now, "Wait just one no-draft minute!" you might complain, arguing that, "Tri bikes differ in other ways than just in their geometries! What about aerodynamics?!"
True dat. But here's what's even truer: Eighty five percent of what matters aerodynamically is your position on the bike; the other fifteen percent is important, and is worth :30 here and :45 there, but let's find those bikes that'll fit you, and that'll handle well underneath you. Let's do that first. Furthermore, you're now in the BIKE FIT section. If you want to know about tube shapes, saunter over to the tech section of Slowtwitch.
At this point, you might be wondering, "What do these Slowtwitch people actually believe about bike fit? Is there a systematic theology?"
In fact, there is. Are you ready for our Summa Theologica? It's the F.I.S.T. Method for fitting triathletes to their bikes, and that link will take you to the first of 11 articles on the subject, which ought to be read in order. Following that intro article come our Ten Commandments of bike fit:
1. F.I.S.T. axioms
2. F.I.S.T. protocol
3. Measuring conventions
4. Seat height
5. Cockpit length
6. Hip angle
7. Armrest drop
8. Tools of the trade
9. Your bike's "waistline"
10. Translating fit specs to bike specs
You'll note a mention in these articles of a new metric for measuring bikes, developed here, which we call Stack and Reach. We develop this theme further in a set of articles on the subject, and you can read about them in this series of articles:
- Stack & Reach Primer: Chapter One
- Stack & Reach Primer: Chapter Two
- Stack & Reach Primer: Chapter Three
Once you get your arms around the concepts of stack and reach, you'll find that bikes today are often sized by manufacturers in unhelpful ways that make little sense. We warn you to beware of T-shirt nomenclature, and further in a follow up article on the subject.
What about custom bikes? Are you a good prospect for one? How do you develop a geometry for your custom bike? One article that'll tell you if you're a likely candidate is about folks with long legs and short torsos.
When you get to the point where it's time to develop a geometry for your custom bike, we've got a custom tri bike geometry calculator online to help you in your quest.
Remember this: Discomfort you experience on your bike may not be related to bike fit per se. Discomfort is often due to point tenderness, or friction, and if you follow the links to those articles you might save yourself a lot of money by fixing only what ails you.
We've got articles describing things to think about if you buy a one-piece, stem integrated handlebar. And speaking of handlebars, we spend a fair bit of time on the subject of the shorty bar, a design you'll find referenced over and over again, specifically for those who choose to ride a road race bike, set up as such, in triathlons.
Let's say you've wrapped your brain around most of the subject matter above. There are some little helpers that might make your experience with bike retailers more substantive, such as our discussion of remote tri bike fit and if you want to go down deep and stay down long, here's a follow up specifically for retailers and manufacturers.
Finally, don't assume that it's just "fit" we're interested in here. How you ride your bike, technically and tactically, is just as important. But you'll be less likely to find those discussions in this section. You'll more likely see them in the Cycling sub-category of our Training section.
This is not an exhaustive list of the articles in the Slowtwitch Bike Fit section, but reading these articles will tell you most of what you need to know to make informed and effective choices. This is just the sort of stuff we teach retailers, coaches and manufacturers in our F.I.S.T. Tri Bike Fit workshops, and you can find a list of retailers who've been through these workshops, and who own the tools specific to these techniques, by searching our retailer database.