This post originally appeared at Red Kite Prayer in 2016. We’re reposting now, because we talked about it on The Paceline this week, and because the geometry nerds among you will enjoy it. We also couldn’t resist serving you a piece with this title, 7+years after it was written.
I’ve got this hangup about accuracy. I hate seeing history rewritten, or the present adjusted to conform to the past. Case in point, most cycling fans claim they not only hate Lance Armstrong now, they always hated him. It’s a pretty convenient myth. Certainly it’s out of fashion to claim we enjoyed watching him put the wood to Jan Ullrich, Ivan Basso and Andreas Klöden, but for most folks to say they never liked him, well all those photos on Facebook of people wearing yellow bands would suggest otherwise. Most of us like watching him race; we needn’t be embarrassed by that.
I have the same reaction when people like to talk about how much they love the handling of Italian bikes, how they have always loved the handling of Italian bikes. I don’t fault anyone for saying that. The fact is, for anyone who thinks that, it’s because there are companies out there that have intentionally snowed us. The truth is Italian bikes today bear little in common with the steel rigs many of us cut our teeth on.
What follows is less a diatribe against any particular bike company and in truth an effort to give riders an accurate picture of how bike geometry has changed.
BEPO: Before EPO
The chart that leads off this piece is the geometry for what Eddy Merckx was riding circa 1970. The basics are unsurprising: 58cm seat tube, 56.5cm top tube, 73-degree seat tube angle, 40mm fork rake and a bottom bracket height of 26.5cm. What is unusual is the 72-degree head tube angle, which when combined with the 40mm rake yields a trail of 6.84cm (this last detail the chart actually gets wrong). The 72-degree head tube angle is why a bike with a 56.5cm top tube can possess a wheelbase of 100cm. Because BB height is dependent on the tire used and can be surprisingly variable, I’m going to talk about BB drop. The Merckx had a BB drop of 75mm.
This is a bike that turns only when you tell it to, and will rail down mountains.
Though Merckx was Belgian, his bikes were built by Italians—Masi, Colnago and DeRosa all supplied him with bikes at some point—and the geometry he rode was distinctly Italian.
Let’s fast forward to the 1980s. From the rise of LeMond through to those last five years that steel was the predominant material ridden by the pro peloton, little had changed from that early Merckx. Still common: 40mm rake, a 73-degree seat tube angle, a BB drop of 75mm. The big difference is that the head tube angle had steepened by a full degree to 73 for most Italian bikes.
Across the pond, here in the U.S., the bikes were quite different. Your average Serotta, Specialized or other race bike was likely to have a BB drop of 70mm—5mm higher, a 73-degree seat tube angle and either a 73.5-degree head tube angle paired with a 40mm-rake fork, or a 73-degree head tube angle paired with a 43mm-rake fork. Either way, you get 5.9cm of trail.
In short, you can sum up the difference between Italian rides and American rides this way: the Italian bikes had a lower BB and more trail compared to American bikes.
So why were the American bikes different? According to the people I’ve talked to, there is one big reason. The single biggest reason is domestic racing. Because Americans were racing criteriums and pedaling through the corners, the BB was raised and the trail decreased in order to keep the bike maneuverable. The Italians were designing bikes for racing grand tours—day in, day out, and in the mountains.
It’s the American geometry that was used when Asia began tooling up for carbon fiber bike production in the late 1990s. That’s because the American companies were the first to go to Asia to produce carbon fiber frames.
So what’s the difference between those two bikes, practically speaking? Talk to anyone who owned an Italian steel bike that was produced in Italy before Miguel Indurain’s last Tour win and they’ll talk of the bike’s handling in reverent tones. Telepathic, magic, confidence-inspiring; you hear the same descriptors used over and over. Nothing descended as well. And that was a function of the lower bottom bracket.
The America bikes, by comparison, were great for threading the eye of the needle, going flat-out through the last corner of a crit and going straight when you stood up to sprint. The higher the BB, the more it tracks straight when you stand.
It’s the move to Asia for carbon that caused an irreversible shift in the geometry of production bikes. Not for the American companies, but for all the European ones. Look at today’s European companies and their bikes have the same geometry as the American ones, by and large. You’ll see some variation in head tube angle and fork rake, but with few exceptions they run in the 68 to 70mm range of drop.
Over the years I have asked a number of people why the Italian companies changed their geometry upon sourcing carbon fiber from Asia and the only answer I ever received that seemed credible (partly because it was off the record) was that the guys who first made the trips from Italy to Asia for sourcing weren’t the designers; they were executives, usually in charge of sales and marketing and had no clue about the geometry of the bikes. The Asian companies ended up doing all of the design work and stuck with the American geometry because no one asked for bikes with a lower BB or more trail.
In a few short years Italian geometry went almost extinct.
Carbon fiber bikes produced today are notably different than those being produced in 2000. They are much stiffer in all the ways that are critical to handling. One of the reasons bikes in the 1970s had slack head angles, low bottom brackets and not much fork rake was that they were pretty flexible and you had to make those concessions in order to make a bike that you could handle with precision on a descent. Now that they are much stiffer, we’ve seen trail drop steadily, from 5.9cm to 5.6 and more recently to 5.3. On occasion, I’ve seen some big bikes with as little as 5.1cm of trail. Companies wouldn’t put bikes with so little trail on the road if the forks weren’t significantly stiffer than they used to be. You need precise handling in order to control a fork that steers so quickly.
Unfortunately, there’s a weird flip side to this. When you look at some European companies’ efforts to revive old steel models, in many instances they are building their steel revivals around current angles.
For riders who had a Colnago, Masi or Pinarello back in the 1980s or ’90s and have missed the way that bike handles, there are very few options other than going with a custom builder. Ironic that the easiest way to get that Italian stage race geometry would be to talk to an American builder, but there it is. There’s one final, notable wrinkle. The rise of the gravel bike, a bike different from cyclocross bikes, that has seen a return to that 1970 Merckx geometry with a slacker head tube angle and lower BB. The one difference is more fork rake. Where the Merckx had a 72-degree head tube angle with a 40mm rake fork, today we’re seeing some gravel bikes with a 72 or even a 71.5 head tube combined with a 50 or 55mm fork. The driver is that big tire and the need to avoid toe overlap, or at least minimize it.
So there; I’ve said it. Italian bikes aren’t Italian bikes anymore. Not in handling, and certainly not in construction. There are exceptions, but those exceptions are all produced by smaller outfits. If you miss those bikes of yore, talk to a custom operation.