geometry ⁽³⁾

With a fleet of six bikes, of which three are surface-agnostic SUBs, commonly better known as gravel, all-road, or adventure bikes, I didn’t need another one this year. But when I first spotted the Marin Gestalt X10 last November, I knew I had to get one. The bike is slacker than my FortyFour mountain bikes, with a 67.5º head angle. Reach is 63mm longer than my Nordest Albarda and 68mm longer than my Volagi Viaje. The Gestalt’s wheelbase is 95mm greater than the Nordest and an enormous 124mm more than the Volagi. It’s a massively different bike. And that’s the reason I bought one. Some time down the road, I’d love to design the perfect SUB frame for myself. It only makes sense to go down that path with years of cycling under one’s belt, which I have, and countless hours spent on a wide range of bikes. And that one can never have enough.

The bikes I ride on pavement or gravel are more than road, all-road, or gravel bikes. They are efficient, practical, surface-agnostic bikes that bridge the functionality gap between road and off-road. In this post, I want to look at the geometry of the bikes I have ridden in the last nine years.

The numbers below are from Bike Insights, from Stooge and from Kris' drawings I imported into QCAD, an open-source 2D CAD system. While some people totally geek out about bike geometry and could hold a 2-hour monologue on head tube angles alone, I'm really not a numbers expert when it comes to cycling. Whether the topic is frame geometry or watts and whatnot, I'm not the expert to talk to despite 36 years of cycling. I don't sit on enough bikes to have an expert opinion on what a slacker head tube or longer trail do to a bike. Sure, I have an idea about it, but with the rather small number of bikes I've ridden over the years, I'm still far from having earned the degree of "armchair geometry wizard." The 36 years in the sport have given me the ability to know what works for me; no more, no less. Changes I've made over the years happened gradually. Being limited to riding only the bikes I purchased, my experience and knowledge of the sport are fairly narrow. I know nothing about suspension and bikes equipped with it. I know even less about bikes powered by motors and honestly don't care to know anything about them. When the time comes to look for a new bike, and it's not made to measure by a bike builder, I usually compare the geometry to the bikes I already own. Often, I draw the frames up in CAD and overlay them for comparison. This also helps to figure out what stem to select to achieve a similar position on a new bike.