Handlebars have been trending wider for many years. Few of us are riding the 580mm-wide Answer Hyperlite bars that were the rage fifteen years ago, but that doesn’t mean you should rush out and buy a handlebar that’s wider than a Honda Civic just because it’s what your favorite pro downhiller is riding.
If you're thinking about going wider, do it for function, not fashion. And before doing it at all, weigh the pros and cons.
Specialized fit professor Aaron Post recommends balancing biomechanics with terrain and riding style to find your ideal handlebar width
The Evolution of Wide Bars
Like the rest of the components we ride, handlebars have evolved dramatically since the early days of our sport. In the beginning there were just ‘mountain bikes,’ today we have all manner of species of knobby-tired machines—cross-country, trail, all-mountain, enduro, freeride, downhill—along with components designed specifically for these breeds.
Noel Buckley is the owner of Knolly bikes. He has a background in engineering physics and has seen the mountain bike market diversify over the past two decades. “The changes in riding style, advances in full suspension bike geometry and suspension travel, the rise of new applications (e.g. downhill bikes) have allowed handlebar manufacturers to go wider than the standard cross-country bar of 20 years ago,” said Buckley.
His engineering background lends itself to an analytical view of handlebar width, though he admits there’s no hard science to finding one’s ideal handlebar.
“There are no simple answers here: even making a table of rider height versus frame application versus suggested bar width would be difficult and probably not overly useful. Local factors such as trail design, trees, rocks, and the balance of climbing versus descending might sway a given rider's preferred bar width by 25-50mm,” said Buckley. "The obvious argument towards using longer handlebars is that they give you more leverage (or torque) to steer the front wheel: this is supposed to make controlling the direction of the bike easier. In general, this is correct. At the end of the day, it is very difficult to say anything more than wider bars = shorter stems, smaller riders = narrower bars, and low and slack bikes can typically get away with wider bars than steep, tall bikes. But even these dogmas are being challenged by the increase of 710-740mm bars in the trail bike market—bar widths that were decidedly DH oriented less than half a decade ago."
Wider Does Not Necessarily Equal Better
Like most things in life, handlebar width is best approached with an eye towards moderation and practicality. If your trails are very tight, heavily wooded, and lack high-speed sections then a wider a bar may be a hindrance. If your handlebar is so wide that you are riding with your arms extended and your elbows locked you will find it very hard to react to obstacles. Likewise, if you’re slight of frame with narrow shoulders, wider bars may cause discomfort.
You shall not pass!
Aaron Post is a fit professor with Specialized. He notes that while there are tangible benefits to going wider, wide bars are not for everyone, and my have little to no benefit, depending on how and where you ride.
“The wider trend has come from riders who are riding very technical, very fast terrain, where the trail is literally starting to pull the bar out of the rider’s hand. If your trails are not particularly technical the need for a wider bar diminishes. More often than not, it is biomechanically easier for a rider to support themselves with a narrower bar, you would want to go wider as the terrain dictates,” said Post.
Post uses push-ups as an example. It is much easier to do a push-up when you hands are placed just to the outside of your shoulders than it is when your arms are splayed out to your sides. Signs that you may have gone too wide include pain or discomfort between the shoulder blades and upper back.
Handlebars, Stems, and the ‘Golden Ratio’
As your handlebar length increases your reach decreases. A wider bar will shift more of your weight forward. Hence the need to run a shorter stem to keep your weight centered.
A stubby stem helps to keep your reach relatively consistent when running a wider bar
The general rule of thumb is to maintain a 2:1 ratio of handlebar width to stem length: for every 20mm increase in handlebar length you should reduce your stem length by 10mm. So if you’re running 660mm bars with a 100mm stem and want to try a handlebar that is 700mm wide you will need to pair that 700mm handlebar with an 80mm stem to maintain a relatively consistent position on the bike.
Like most rules of thumb, this is 2:1 ratio is by no means absolute. And, as Post points out, it is only useful if you’re starting from a comfortable fit position. “If you’re already unhappy where you are all bets are off."
Test Many Times, Measure Twice, Cut Once
It’s important to remember that just because you bought an 800mm-wide handlebar does not mean you’re locked into this length.
“Manufacturers often try to make the bar a bit longer than required to give users the option to shorten it to the correct length. Riders may mistake this extra length as being appropriate for their height, bike setup and riding application,” said Buckley.
Work outward from your existing position to find your ideal width
It’s easy to experiment with handlebar width, particularly if you are running lock-on grips. With a wider bar installed, mount your controls in the same position they were on your narrower bars and gradually move them outboard until you find a position that’s to your liking. (This may require the use of several different stems, too.)
So spend a couple hours experimenting with fit and be sure to install bar plugs before taking to the trails!