I’ve had a couple of questions recently regarding what kind of bike to buy for some cross and gravel action and what is the difference between them. This is probably going to date as the genres progress but at the time of writing this is my take on it…

Bottom line, both are suitable for either (or either are suitable for both maybe?) and a gravel/cross bike will be a ton of fun, but there are differences, some of which you can change easily and some which you can’t. Some things also depend on the brand and the price point…
Things you can’t change:
- Geometry – the options are “long and low”, “high and tight” or in some cases somewhere in the middle. Euro cross bikes (eg Ridley, Stevens) have high bb’s and steep angles (“high and tight”) – they are designed to be fast round euro style cross courses (read mud, sharp bends). Being high and tight means they are also relatively not so stable at speed.
“Long and low” geometry (low bottom bracket, longer wheelbase and slacker geometry) has come out from the (more) west coast US style of cross racing (“grass crits”) where speeds and grip are higher and bikes can be laid into fast turns. Companies like, for example, Specialized and Santa Cruz offer bikes of this style.
Gravel bikes tend to be on the slacker end of the spectrum to handle faster descents often found on gravel routes with more stability.
- Tire clearance – manufacturers are increasing the clearance for their bikes these days so this is becoming less of an issue but 700x40c is pretty typical for gravel and there is no width restriction for cross either (for most racers racing at grass roots level). Some cross bikes do still have limited clearance though so that is worth watching out for. Some gravel bikes also take 650b wheels with capacity for MTB style (read 2″) tires. The outer diameter is similar to a 700c wheel/tire but the benefit is you have a lot more cushioning and with the right tire drag won’t be too bad either. Its personal decision if you want to go the 650b route, it will require 2 sets of wheels or you to make a decision on one size or the other though.
Things you can change:
- Gearing – cross bikes typically have 1x with a max 32 or 28 designed for flat(ish) cross courses, making it hard if you take it on big climbs. Switching to a wide ratio and/or 2x is possible (2x may not be possible depending on frame) so not the end of the world but can get expensive depending on what you are looking for. Gravel bikes have the big gear range but if 1x you have big jumps between the gears which isn’t so good for cross (or riding in a bunch), plus you tend to spin out at 30-35+mph if you want a gear small enough to get up steep climbs too.
- Tires – another changeable item – gravel bikes generally have 35mm wide tires (as a minimum, with a tread pattern more akin to semi slicks. These offer good shock absorption and roll better but have less grip. Cross bikes (still) tend to come with 32c intermediate tread tires which drag more on the road but grip better. Some cross frames have limited clearances for tire width so watch for that if that is important to you.
Tires have the ability to transform your ride for the better and/or the worse depending on choice so everyone is always looking for the “holy grail” tire, which of course doesn’t exist. When considering which bike to go with, a critical aspect is to make sure you have the frame clearances that will to enable you to ride wide tires. If you race cross, check with your local organizers but in socal, unless you are racing the few UCI sanctioned races you won’t be checked for tire width so a wide tire for cross can be the way to go.
Another point about gravel bikes vs cross bikes is that gravel bikes often come with utility functionality such as bosses for fenders, extra bottle mounts, rack mounts etc. To save weight, cross bikes are often striped of all of these features save one or two bottle cage mounts inside the frame triangle.
Whether you go for a cross bike or a gravel bike, you will of course be able to use that bike for the other discipline, it may not be perfect, but it will still be a ton of fun. And all this of course confirms the saying that the correct number of bikes to own is “N+1” (where N is the number of bikes you currently own).
Enjoy the dirt, there really is nothing like it.