I've been using 44 cm bars for years with total comfort except for the standard drop/reach being a tad far but that's all we had until shallow drop/compact came out. I'm switching to a shallow drop and was wondering if I should go to a 46cm? I guess that would open my chest a bit for breathing yet be less aero in exchange for it--maybe other advantages/disadvantages? 44cm has felt fine all this time and my bike was pro-fitted with a 44cm as was an older bike. I should add that I mtb a lot and am using a much wider bar than I used to use. Thoughts?

What size suit jacket do you wear? The jacket size in inches will approximate a suitable bar width in centimeters.

Approx is correct. As an example, I wear a 42-Long jacket (6-1 with a long torso/arms) but two bike fitters spec'd me with a 44 bar. I used to use a 42 bar and it did feel narrow, so I liked that they moved me to a 44. Is going to a 46 even better based on my points in above post?

Only you can answer that, but a 46 cm bar is huge. There is nothing about drop and reach that relates to width. They are independent of each other. It may be right for you, but what would a really big guy use? Try it if you want. You can always resell it on ebay if you have to.

I went from 44cm to 46cm bars on one of my bikes. I've made it work, but if I had to do it again I would have stuck with the 44cm width.

Not really. As long as the bar is not too narrow, going wider won't really open your chest any further. And going narrow doesn't really restrict breathing anyway - you use the diaphragm for efficient breathing, not the expansion of your upper chest - and your elbows and upper arms don't have to be in line with your wrists and forearms. On mountain bikes, wide handlebars are used for control primarily. The only relevant factor for road bicycle bar width is what feels comfortable.

This is true.

You don't know what you're talking about, so don't go there. Volumes have been written about correct and complete breathing. Your statement, in particular the part about chest expansion, is just plain wrong.

OP, unless you're having problems breathing, don't think about it too much.

Talking about personal experience only - as long as I'm not trying to make my elbows touch, the width of my arms is not restricting my breathing. I am so very deeply sorry for using layman's terms to explain how this feels for me. I will not be posting on medical or sports science forums any time soon.

FWIW, I find breathing no less or more easy on my 44cm road bars compared to my 71cm MTB bars..

A significant minority of pros are starting to use extremely narrow bars, like 38 cm bars. Trust me, if they could go faster, climb faster, time trial faster, etc, on wider bars, they wouldn't be trying narrower bars. Not only that but many pros are shying away from super wide bars. Lemond at times used extremely wide bars for his shoulders. Nowadays you don't see those 44s or 46s in use like that.

Although you may consider comfort, etc, for wider bars, the pros will regularly ride 5-7 hours. If it was that uncomfortable they'd use a different bar. It's not like they're paid to use a narrower bar, as long as it's the right brand (in most cases).

My shoulders are probably appropriate for 43-44 cm bars but even the batch of 42s I've bought/tried this year seem super wide. I prefer the old 41 cm bars that I've used for decades. I'll be trying 40 cm bars over the winter in preparation for 2014.

Having said all that I'll sometimes switch bars in the off season, for those long, steady, low-moderate effort rides. I'm not doing major efforts so I spend most of my time on the tops. For those rides I prefer a wider bar, like a 42. On our tandem I have 42s because sometimes you need that leverage. 44s felt a bit big so I stayed with 42s.

Your mention of closely sized 41 cm bars and 42 cm bars reminds me that folks need to know how the bars are being measured, center to center or outside to outside. It makes a big difference, about 2 cm. So the difference in just how the bar is being measured can be bigger than the size difference between two bars. Most bars are measured c-c, but I do see some reference to o-o sizing occasionally.

With the exception of Chris Horner, who seems to prefer outrageously wide bars for a guy of his size, 46cm or something like that.

Personally, I think the idea that wider bars "open up your chest" and allow you to breathe better is basically a myth. There may be some bar width so narrow that breathing is impeded, but I think the arms-outstretched riding position prevents this from being an issue, at least at the widths in which handlebars are typically available. If a rider is having breathing issues related to fit rather than health issues, I would look at handlebar reach and drop (from the saddle) long before looking at handlebar width. Running narrower handlebars will, if anything, make riders slightly faster because the aerodynamics are better. Although I wouldn't recommend going to narrower bars in the hope of buying some free speed, as the differences are pretty small and comfort is a much better guide to handlebar width.

There's been a tiny but visible movement out there that believes wider drop handlebars are inherently more comfortable than narrower ones. This point of view is more prevalent among the Rivendell/Velo-Orange/randonneuring and/or pseudo-randonneuring type of cyclists (I'm trying not to dis anyone here, I don't mean to suggest there's anything wrong with these people). It might be true for some people, and it might especially be true if you tend to run your drop handlebars above the height of the saddle, and therefore with less weight on your arms. For me, personally, I discovered after a couple of years of experimentation with 42 and 44 cm bars that I actually find wide drop bars to be quite uncomfortable and am much more comfortable with 38 and 40 cm bars, keeping in mind that I'm a slightly-built guy with fairly narrow shoulders.

Just curious how my extemporaneous correlation between suit jacket size and bar width works for you. You say you are slightly built with narrow shoulders. What size suit jacket do you wear (if that is not too personal a question)?

TT guys breath OK with their elbows nearly touching. IMO, where your arms are does virtually nothing to your breathing as they they hing in the shoulder sockets which are outside of the ribs and chest. And, if your riding with your elbows bent (as you should) then the angle of your upper arms is going to be wider than your forearms.

How do hipsters breathe with their narrow @$$ bars?

Narrower bars impede the amount of torque you can put on the bars in a sprint. Wider may be uncomfortable. Comfort being important, especially the longer you are on the bike, is where the importance of the shoulder measurement.
If you imagine sprinting, you are pulling up on one drop & pushing down on the other. If the bar is wide you are stretching further, when pushing down. On a narrow bar you are losing some power when pulling on the drop, because your hand is inside the the square lines of your shoulders. It's a leverage thing. As well as comfort, depending on your riding style.
Another example, you are climbing, out of the saddle. Your hands are either too wide or too narrow with the width of your shoulders. In this case you are likely compensating in the same, but different, way.

Although technically, from a physics point of view, narrow bars give you less leverage, you'll find that absolutely pure sprinters prefer a narrower bar to a wider one. You don't see track sprinters using wide bars.

From bikeradar:


I find that I sprint slower with wider bars. It's not the leverage, or lack thereof, that hurts me. It's that I can't rock the bike as quickly or forcefully with wider bars - I want to be able to snap the bike from side to side. I went as wide as 44s for regular use, with 42s being "wide" to me. I ran 40 cm bars for a long time, then moved to a 41. I plan on moving back to 40 cm bars. With all those bars I did long rides, 5-7 hours (to me that's long) with a max of 8-10 hours on some of them (mostly the 41s and 42s).

This is me on 42s (photo by Bob Griffith). It shows how narrow the bars are relative to my shoulders. I won this race, which I actually forgot about until I went looking for these pictures:


Road sprinters will use wider bars than track sprinters, although, again, there are some riders using 38 cm bars who by conventional wisdom ought to be on 42s or 44s.

Greipel, from Ridley's site, who has sized down to a 38 cm bar:


A few Lotto guys use narrow bars after Adam Hansen got them to try the bars. Greg Henderson, another big guy on Lotto, uses 38s (or 36s but I haven't seen that referenced in more than one place). Sieberg uses narrow bars too, as well as Roelandts.

Hoy has since moved back to a slightly wider bar. Nowhere near what "conventional wisdom" recommends though. I think he went from 36cm to 38cm, I believe.

I use 42cm on the road and 38cm on the track. I have 44 or 46cm wide shoulders. At one point, I was using 44cm wide bars; I went to narrow bars to get a bit more aero and a little narrower to maneuver better in a field, then found I liked them much better for sprinting.

It would seem from a physics standpoint that you would have more leverage at equall length. Do you feel that you have more power because the throw of the bike is quicker? Thinking about it, I suppose the bike could be thrown further , side to side with a narrower bar. That still leaves the inner bar at a geometrical disadvantage. Edit]. I did a little reading. It seems as there is another advantage to smaller bars. As messenger riders, a sprinter needs to navigate some pretty intense traffic. Keeping things compact would be advantageous. Still curious about power numbers? Not being a racer, at my age, I'm sticking to my square bars. I do enjoy the insight, however!

Wider handlebars have slower steering than narrower bars. In other words, to turn the front wheel a given number of degrees, a rider's hands have to move further forward or backward on wider bars than on narrower bars. That is because the lever arm is longer on wider bars.

Wider bars give more leverage to turn the front wheel than narrower bars. That is also because the lever arm is longer on wider bars. This may be much more important in off road riding than in on road riding.

Narrower bars are more aerodynamic than wider bars, but in the real world, this may or may not make any appreciable difference. It depends on the rider and the circumstances.

Narrower bars can navigate through smaller openings than wider bars, however the difference is only a few centimeters. For a bike messenger in New York City or a racer in a peloton that might make all the difference. For most everyone else, that might not matter at all.

Being able to breathe better with wider bars than with narrower bars is very much open to debate. Time trial riders use a tremendous amount of oxygen during their competitions, yet they have no problem breathing with their arms close together and their hands right next to each other.

Some people like wider bars, and other people like narrower bars. This may be due to the rider liking quicker or slower steering, because the rider grew up with a particular type of bar, because of the popularity of one type of bar over the other, because one type of bar "feels better" to the rider, because the rider has heard that one type of bar is better than the other, or because of any number of other valid and invalid reasons.

In a world of hyperbole, it is important to keep one's head and realize that one size does not, in fact, fit all. And, the worth of wider or narrower handlebars needs to be determined on an individual basis.

I think this is the most accurate statement on what width bars to use

For power I don't have enough data on any narrow bars. I've been on 41s for most of the time I've had a powermeter and recently went to 42s. I feel slower in the sprint, feel uncomfortable, and in the only comparison I have I've been slower (race clip below's sprint is slower than last year's sprint).

Narrow bars help me feel like I can navigate traffic better, but honestly I can't say for sure if I wouldn't have gone through a gap with 42s vs 40s vs 44s for example. I race pretty conservatively - one of my personal rules is not to initiate contact to gain tactical advantage. Therefore I won't push or shove a rider out of the way, at least not intentionally. So although I've slammed into a rider accidentally as we both dove around a slower rider and ended up in the same piece of road, I won't reach out and push someone with my hand or head or whatever. I ride defensively to protect position, of course, and wider bars would actually help a little with that (and I hadn't thought of it until just now).

However I think that bike and body placement play a stronger role in gaining/holding position than just bar width. For example in all my examples the rider, when sitting square on the bike, is much wider than the bike. So how would narrow bars help? Well when I slip through a narrow gap I turn my shoulders to the side, making me a bit narrower.

When trying to hold position it's all about trying to keep a rider from taking the wheel from you. To hold the wheel you need to either place yourself between the rider in front and the wheel taker, if in single file. If side by side then it's about being more forward. In this latter situation I think wider bars would help a bit. In this race a fellow BFer (shovelhd) leads me out and two riders make half hearted attempts to take his wheel:

What "holding position" becomes is a battle to intimidate the other rider by not moving away when they get closer. I call this zone around your bars and front wheel "The Sphere", a personal space that when violated makes you feel really uncomfortable. By practicing contact side to side and fore-aft a rider can reduce their Sphere to near negligible size. This in turn allows them to hold a wheel even when pressured to move by another rider approaching closely.

As a general observation it's much, much easier to take a wheel than to hold a wheel.

Finally, watching the pros race on TV (I've never been at that level!), I don't think wider bars would help but I think narrower ones would. I've seen overhead footage of, say, Cavendish, holding his leadout train's wheel. btw he runs 42 cm bars, according to what I've seen. If his train gets derailed he's very good at finding his way to the front. He also will bob and weave on his bike to clear small gaps (so he'll turn his shoulders sideways to clear a gap, or tilt the bike away from him, effectively making it narrower), and generally speaking he doesn't initiate contact, either in the sprint or in the lead up to it. Of course he defends his position but there are sprints where he eases and loses his train rather than pushing and shoving his way through a hole that's closing.

The key is that he relies on his speed to win sprints. He's not like, say, Bettini, who got DQed for unsafe riding after winning a sprint in the Giro. Bettini is not as quick so he resorts to physically blocking other riders to try and defeat them. Sometimes that's okay, sometimes it's not.

42 seems wide for Cav. He's a little guy. I'm not insanely broad shouldered but, I am 6' & have a 44cm c-c width bar which measures square. I wonder ifthat measurement is C-C?

My suit jacket is a 36, extra-slim fit.

Traditional wisdom would seem to be accurate here. Your shoulder seam to shoulder seam measurement is likely 36 cm. No wonder you didn't care for ginormous bars.