by Jesse Schultz
When I look at a gravel bike, I see a rowdy-ready road bike, but I’ve heard it said more than a few times that a modern gravel bike is substantially a resurrection of the rigid steeds we knew as mountain bikes of the early 1990s...dressed up in 2020s price tags.
Flashback to 1992: I'm rocking a shiny new midlevel BRC mountain bike, egged on by my buddy. “Dude," he'd said, "this has you written all over it.” And, just like that, my hard-earned $900 crossed the counter. I was set to bend a town’s share of parts in the most awesome of ways.
That chunky piece of ancient awesome was rocking a pair of 26-inch wheels with 2.1" Panaracer Smoke and Dart tires. Bouncy parts were still just a magazine topic on the trails, so this bike was fully rigid. Yeah, I was livin' large!.
This bad boy was only marginally slowed by the latest cantilever rim brakes (cantis). I still believe their main purpose was to elicit enough fear in a rider pinballing down the tech that brakes would not be a factor in line selection. Instead, the action of squeezing the lever to the bar provided a modicum of stress release.
The gear spread was wide in the front (22-44 triple) and short in the back (11-28 9-speed). The rear cassette was from the road scene, while the front assembly was probably robbed from touring bikes.
The handlebar and stem geometry were constantly evolving: bars were cut down, but then the steering was too quick, so longer stems were bolted in to slow the steering down. Then we added bar-end grips, but now the bar was way too short, so we started all over and just ended up with the longest stem available.
Yeah, we had no idea what we were doing, but it gave us a place to dump our money.
So, where does that mental hairball from the past lead me?
Well, the biggest thing that smacks down the 90s-MTB-to-gravel-bike comparison is the drop bar. While super Johnny T [racing legend John Tomac] rocked a drop bar once at a smooth downhill race, it wasn’t a thing. A flat bar on any bike changes everything. This piece alone drops a water balloon on the candle of comparison.
Next up would be the wheels. Most current gravel bikes are rolling on 29er rims, while the ancients rocked big hucks on little 26” wheels. The tangential angle of a bigger wheel makes for faster rolling on rough ground and ‘monster trucks’ over roots and holes–think along the lines of a basketball vs a golf ball rolling over a golf hole: 26” knobby tires would never be the first choice for a 100-km road ride, while 700x40s are not bad. The difference in wheel size drops a wet towel on the comparison for me.
While wider tires are sweeping the gravel world, they are still not the same width or knobbiness of those 2.1 Panaracers or the 2.4s that came shortly after. This is like comparing apples to tomatoes: both are red round fruits, but...
The similarities of the drivetrains are that some gravel bikes are using a front derailleur, and the 90s MTBs also had a front derailleur. However, the derailleur of decades past had a 22-tooth spread across three chainrings whereas the current GRX FD has a paltry 17 across two chainrings. Close enough on that one.
Of course, in the three decades since those dreaded canti brakes, disc brakes have finally made it onto road and gravel frames. While these brake calipers are predominantly flat-mount style, the lite beer of the brake world, they are still considerably better than those 90s cantis of carnage.
So, here's where I get to my point. Current trends in gravel bike bikes are actually mimicking modern-day MTBs:
Steer tube angles are getting more slack–out to 70° in some cases. This makes for a more stable bike off-road when combined with short offsets. When you think of a hardtail MTB with a 65° head angle, realize that the fork will compress, so the head angle will be closer to 68°, whereas with a rigid fork, that angle is always 70°, so the difference, while not small, actually isn't that big
Longer chainstays offering better grip and putting the rider further forward for steep, loose climbs (MTBs have two schools of thought on chainstay length, but that is a different chat)
Drivetrains are essentially MTB derailleurs with clutches and wide-range cassettes with a single chainring
Some gravel brands are touting “MTB geometry.” This is essentially making a longer top tube and combining it with a shorter stem to move the rider weight forward.
Many seat tubes accommodate dropper posts
Proper suspension forks are available and can be retrofitted to most frames
Plus a number of components that span many types of modern rides, like disc brakes, threadless 1.5” tapered steer tubes, thru axles, a sloping top tube and tubeless tires
After all that, I offer my summarized response to the question, “Aren’t current gravel bikes just 90s MTBs?”
Not really. Given the differences in the handlebar layout, regardless of MTB era, and that suspension and dropper posts are becoming common on gravel bikes, I believe a current gravel bike has much more in common with a current hardtail MTB than it does with a 90s one.
Now, let’s go have coffee.