Skip to Content


Choosing a Base Bar

Written by: Greg Kopecky
Date: Mon Jul 02 2012

I’ll go ahead and object in advance for you:

“But – it’s all about the aero position! Aero or die! Base bar? Oh, yeah… I have one of those, I think. Carbon ones are better, right?”

There will be objections. No, this is not the conventional view. But - my job is to stir the pot and get your gears rolling in the ol’ brain room. Let’s begin, shall we? We all understand that road bikes feature a drop-style handlebar, while triathlon bikes (usually) feature a base bar with clip-on aero bars. Base bars can also be called “pursuit” bars, and I’ll consider these terms interchangeable. While many people might not think about base bars very much – or think they matter much at all – I’d like to get you thinking about it. They matter. Really.

They matter for things like your fit, comfort, and most importantly safety. As well, your choice of base bar is highly dependent on your choice of bike, aerobar, and even crank length. Maybe your bike’s head tube is a touch too tall for you. Maybe your aerobar pads are a little too low. Or maybe you’ve got oddly short arms for your overall height. These considerations and others affect what you ought to ride… so let’s dive in to the particulars.

Drop and Reach

Similar to road drop bars, a base bar has a drop and reach measurement. Note, however, that it is measured in a different way. On a drop handlebar, the “drop” is measured from the centerline of the stem clamp to the center of the bar at the end of the hook, or drop. For reach, measure from the center of the stem clamp to the center of the furthest point of the bar’s curve, which is right where your shift/brake levers mount. Zipp was kind enough to lend use of their drop bar diagram, which nicely demonstrates how to measure this:



To measure drop on a base bar or pursuit bar, the first point of measurement stays the same – the center of the stem clamp. The second point of measurement, however, is a little more ambiguous. The best way to think of it is this: the center of the bar in the place at which your hands rest while braking (see graphic below).



But there can be other variables at play. Some base bars, such as Zipp’s latest iteration of the VukaBull, feature a hand grip area with a subtle upward slant. The intention with this slant is so you don’t go sliding off the front of the bar under heavy braking, or when you hit a bump. But it does also slightly influence the drop measure. Some other bars, such as most of the offerings from Profile-Design, feature a grip section that is parallel to the ground for the most part, but then it angles up sharply for the last inch or two. Again, this is likely a safety feature to keep our hands on the bar over rough pavement. For bars such as this, I consider the drop measurement to ignore this final upturned section – the measurement is from the bulk of the hand grip, which is parallel to the ground (as shown in the above photo).

And then we have radically shaped bars, such as the original generation 3T Ventus, which really isn’t a bar at all, at least in the sense that it’s not a round piece of pipe. The grips are flat, and quite thin. There really isn’t a “center” of the bar to which we can measure. Also, the bar has an integrated stem, so there isn’t a true stem clamp to measure from. This is neither here nor there, and doesn’t necessarily make the bar good or bad – it just challenges us in terms of defining its’ dimensions. In cases of single piece integrated bars, we really must rely on the manufacturer to come up with “virtual” drop and reach measurements from their design drawings. If I personally intended to purchase one of these bars, I’d want to see it in-the-flesh at the local bike shop, and bring a measuring tape with me. It’s better to be 100% sure that the bar will match your existing bar’s dimensions before plunking down $1,000.

The “reach” measurement it where things really get murky. With base bars, there is no standard. And typically, manufacturers don’t even list this dimension for you. Sure, they’ll tell you the bar’s width, and sometimes tell you the drop. But they almost never tell you the reach. I personally feel this is one of the most important dimensions for safety. Why? To be frank, you can’t safely ride the bike if you can’t safely reach your brake levers, or if they’re much too close.

So how do we measure “reach” on a base bar? I suggest that it begins at the center of the stem clamp area, and ends at the furthest point of usable real-estate on the hand grips. For bars with flat or gently sloping grips, you would measure at the very end of the bar – where your brake levers plug in to. For bars with sharply upturned ends (such as Profile or Syntace alloy bars), this would measure just to the “elbow” of that bend (see photo below). And for the bars with integrated brake levers, I suggest a virtual point in the dead center of the brake lever – effectively where a standard bar would terminate.



In a perfect world, tri bikes would be spec’ced with different reach bars in different sizes, similar to stem length. A 6-foot tall person has longer arms and torso than a 5-foot person – this ought to warrant a longer reach to the hand grip area and brake levers. As an example where this can go wrong, I’ve seen many 7-series Trek Speed Concept bikes outfitted with the Bontrager Race X Lite Bullhorn bar, including the smallest sizes. This bar happens to feature a long reach, and a relatively deep drop. The small size bike is just that – small. It has a 49.5cm effective top tube length. If you’re short enough to need that top tube length and this size of bike, I argue that the particular base bar chosen to be spec’ced on the bike is not appropriate, unless you happen to have very long arms. The bar is long and low, and can leave short riders in a stretched out position while braking. In one bike fitting case with this bike, I swapped a stem out to a downhill mountain bike stem, as it was the shortest option available to us (at 60mm), but the rider was still stretched out too much to safely steer the bike, see the road, and use the brakes. The only two solutions were to 1) buy a different bike with a much shorter top tube to accommodate the base bar, or 2) put a shorter reach base bar, and re-cable the bike. Given the cost and trouble involved, this rider chose option two. But let me be crystal clear: It is not a bad bar, and it is not a bad bike. The two combined in the smaller frame sizes just don’t work together for most people of that height.

Bar Width

As we all know, handlebars are typically available in multiple widths. Not everyone has the same width shoulders, so it makes sense to offer options to accommodate this. But there’s a growing problem in our industry – the options for base bars’ width are shrinking. To be more specific, the total number of options is on the decline, and the average width offered is getting narrower. Now why would that happen, you ask? For the former, we only have to look at cost. Consumers demand high-end integrated carbon aero bars and base bars, which carry a much higher tooling and development cost than your old standard round base bar. Some of these “super bars” have a cost-of-goods approaching that of a carbon bike frame. This being the case, it is always less costly to offer fewer options and sizes. That’s fewer molds, a more homogenous incoming stream of materials, and fewer SKU’s (Stock Keeping Units) for the manufacturer’s warehouse.

The latter problem of average bar width is mostly driven by perception of need. To make a long story short, a narrower bar will always be a little bit more aerodynamic than a wide bar of the same shape. There’s simply less bar there – no two ways about it. We see some high-level pro cyclists choosing this type of setup, read about why they chose it, and assume that it applies to the average amateur triathlete or cyclist. Does it? Why might it not? And does the small aero benefit of a narrow bar outweigh the potential costs? Let’s look at the considerations.

My rebuttal begins first with an admission. For the cost half of the argument, the manufacturers are doing exactly the right thing. McDonalds didn’t become mainstream by offering a diverse menu; they pared it down to a few choices that could be made cheaply and consistently. It behooves the manufacturer to offer less.
What I don’t accept is the part about one size fitting all, or the argument that narrower is better for all riders. Let’s say, for example, that you use a 44cm wide bar on your road bike, measured center-to-center. You also own a triathlon bike, and have your eye on purchasing the latest and greatest carbon integrated base bar/aero bar. But it is only available in one size – 38cm. Now, you may be saying to yourself that the difference is only 6 measly centimeters, so what’s the big deal?

Safety is the big deal. While not an exact science, I want all of my handlebars on different bikes to measure close to the same width. Perhaps you do 50% of your riding on a road bike or cyclocross bike. Maybe you started out purely as a cyclist, and are accustomed to your wide handlebars from years of riding. We all have muscle memory, and get accustomed to the virtual points in space where our handlebars lie. Your hands are used to going exactly to the spot that is 22cm to the left or right of that stem. Perhaps you’re riding and decide to take a drink – but then a small animal runs out in front of you. You instinctively reach for the bars, and your hand knows exactly where to go. But if you just got a new bike with the 38cm base bar, your hand could completely miss – which could result in a very unexpected trip to the pavement. I am admittedly painting a worst-case scenario, but it is not necessarily that uncommon. When you have to react quickly and automatically, you want every chance for the response to succeed.

You may be thinking, “Well, why not just put narrow bars on all of your bikes, so you’re used to it?” While this is certainly an option, I personally don’t see the utility of it. Maybe it’s just me – and I don’t think it is – but a very narrow bar just doesn’t feel as stable or comfortable as a bar of “normal” width. Similar to crank length, handlebar width evolved over time. I have a suspicion that there’s a reason many choose a bar close to 42cm wide; similar to why a crank close to 170mm crank feels good to many people. It just happens to jive well with human anatomy. Perhaps we use just the right amount of range-of-motion in our arms while climbing, or just the right amount of trunk muscles while seated. I’m no physiologist, so these are just guesses – but you can see where I’m going with this.

Most of bar width preference is completely subjective. Where your hands call “home” can vary quite a bit, and there isn’t necessarily a right or wrong. Perhaps that super speedy 38cm bar is exactly what you need. But I suspect that for many men of significant stature would feel more at home on a 42 or 44cm bar. Who knows? My take-home piece of advice on the subject is this: be aware of your bars’ width, and why you choose it. Buy similar to how you (should) buy running shoes: based on comfort and utility, not appearance. If you’re shaky and uncomfortable on a narrow bar, the 'free speed' will be lost as you navigate corners slowly.

Fit Scenarios

I’d like to point out a few not-so-uncommon scenarios of bike fit that can affect which base bar you should choose. While we here at Slowtwitch are very big on getting first things first (the right bike frame), my realistic side knows that this doesn’t always happen. Bikes are given as gifts, bought second hand, or perhaps purchased from a less-than-knowledgeable sales person. This being the case, how can we “fix” that bike position – for both your aero position, and base bar position?
Distance Between Saddle and Bars

This is a biggie for a lot of folks. There are a few factors that determine the vertical distance between your saddle and bars:

-Saddle height (center of BB to top of saddle)
-Bottom bracket drop (how far your BB is below the centerline of the wheels)
-Crank length
-Head tube length
-Wheel size and fork length

The discussion really begins with your leg length and saddle height. If you have long legs and a corresponding high saddle, you’ll need your bars to be high relative to the ground. If you have short legs and a corresponding low saddle, you’ll need your bars to be relatively low.

And of course, we must consider crank length as part of this. If you decided that your old 175mm cranks were no good, and decided to change to 165mm (as the current trend is moving), this would bring your saddle up the same distance – increasing the “drop” from your saddle to your aerobars and base bar. Some folks find that they’re fine with this, and some even intended to flatten their back as part of the short crank change – but just keep it in mind if you do choose to change crank length. There currently isn’t a single mass-market bike out there that is intended to accommodate super-short cranks (i.e. a 150mm crank on a 58cm bike). If you choose to run this combination, your saddle height will be much higher than intended for that frame, putting your bars lower than intended, relative to that saddle height. If you’re long-legs-short-torso, that could seriously hamper your ability to get your bars up high enough to compensate for the crank change.

Take home: If you need more distance between you and the brake levers in this vertical plane of saddle-to-base bar, choose a dropped bar. If you need less distance, choose a flat bar.

Arm Length

Your total arm length affects your base bar choice, and the length your upper half (from elbow to shoulder) affects your clip-on aerobar choice. How does that work out? Let’s say the total length of your arms is short. You’ll need a shorter reach to your base bar. But for your given arm length, the humerus is long and forearm is short. You will need relatively more “drop” to your aero pads, because your elbows are closer to the ground.

Take home: If you have short arms, you want less distance to your base bar (less drop and/or reach). If you have long arms, you want more distance to your base bar (more drop and/or reach). The length of your arm “halves” determines whether you need more or less drop to your aerobar pads. Keep in mind, the two should be considered and fit independently (base bar and clip-on positions).

N = 1

Take me as an example. I’m 6’1”, and ride with a saddle height of approximately 81cm. I have long legs and short torso for my height. This means I need a “short and tall” bike – short top tube and tall head tube. My arms are what I consider to be average length, but with longer forearms and shorter humerus.

If I’m trying to fit on a bike that is long and low, I’d pick a small-ish frame size to get the top tube where I need it. My base bar would be flat (zero drop), because the bike’s short head tube puts the base bar low – I don’t want it too far away from me. My clip-on choice would have to be something that accommodates high pad placement, such as Zipp’s new Vuka Alumina Clip.
If, however, I’m trying to fit on a bike that is short and tall, I’d pick a slightly larger frame size – again, to get the proper top tube length. I would want my base bar to have some degree of drop, because the bike’s tall head tube puts the bar higher up. My clip-on would be something that accommodates a lower pad height – with many choices on the market.

Short Rider Example

Let’s look at the imaginary opposite of me: Someone who is 5’2”, and has relatively short legs and long torso. This person would need a “long and low” type bike, and in a very small size. Their saddle height is low due to their short legs. As for arms, this rider is “average”, but with short forearms and long humerus. This means they would likely need an aerobar with low pad placement – say, Vision Tech. But We’d likely pick a flat base bar with relatively short reach, however, because the rider’s overall height says that they just can’t reach as far as someone who is a foot taller.

Integrated Frames and Bars

You may be thinking that all of this discussion is great, but totally irrelevant – because you may have bought a bike with a completely integrated base bar. Some examples of this include the first generation Specialized Shiv, or the Giant Trinity Advanced. In some cases, you may only have a single bar to choose from, with a single width, reach, and drop. The designers of these bikes essentially have to take an educated guess at the proper dimensions that will fit the middle of the bell curve. In my experience, they do a good job of this, but those on the odd ends of the fit spectrum simply may not be able to ride these bikes – because of the bars. They typically feature a nicely adjustable clip-on system that can get your extensions and pads just about anywhere you need, but the base bar can get largely ignored. Need a dropped bar? Flat bar? Short reach, long reach, wide, or narrow? Unfortunately, you may be stuck. It appears that Specialized recognized this limitation, and revised the newest Shiv to accommodate a standard stem, and any handlebar you choose. Integrated setups tend to have at least some advantage in terms of aerodynamics or weight, but they never outweigh fit, comfort, or safety if they happen to not be right for you.

For Practicality’s Sake

Is this guy still yacking about base bars? I really don’t want to think about it that much. Hold on there – only a few points left, and they are arguably some of the most important.

Keep in mind that cable routing is always a big consideration with any frame or handlebar. The more you integrate, tuck away, and hide – the more difficult it is to do any work on the bike. If you fly to races, I advise building up your bike as soon as possible upon arrival, to ensure that shifting and braking are smooth. If a cable got damage in-flight, a replacement could take hours to install on a highly integrated bike and bar.

As well, I’d like to point out a simply point of practicality that almost no one considers: your bar tape. I will always have a place in my heart for the (now) old-school round aluminum base bar. For one, they’re simple and durable. Next, they’re inexpensive. And last, but not least – you can put as much or as little bar tape on them as you want. Specifically, I love that you can tape all the way around the back corners of the bar. You end up with a huge hand grip section, and a perfect place to lean your bike against the car – on bar tape, rather than bare handlebar. We’ve all had that windy day in the parking lot where bikes don’t want to sit still. Who wants an un-wrappable curvy handlebar to scratch the side of their car while it ghost rides itself away from you? That always bugs me, and is the main reason why I tend to pick a bar with a round transition between the hand grips and stem clamp area. Also, depending on how high your bars are relative to your bike’s top tube, some carbon base bars with exposed sections (that cannot be wrapped in bar tape) can be damaged or cracked simply if your bars turn too far – the back corner of the bar hits the top tube, and in a split second you’ve got scratched paint and quite possibly a replacement of your very expensive bar. May sound impossible, but I’ve seen it happen more than once.

Width Measurement

You should note that not all bars are measured the same way. Most road drop bars and base bars are measured “Center to Center”. This should be fairly self-explanatory: from the middle of the bar on one side, to the middle of the bar on the other side. However, there are a few companies out there, such as Deda and Zipp, who measure “Outside to Outside” – essentially the absolute width of the bar. The quick and rough way to translate between these two measuring methods is to simply add or subtract 2 centimeters. For example, a 44cm O-T-O bar is about the same as a 42cm C-T-C bar. Got it?
Materials and Aerodynamics

Oh yeah – those things. While these two factors are the very first things that some folks consider when looking at a handlebar, I really think they ought to be your last. Get the horse before the cart – have you dialed in the reach, drop, width, grip style, and cable routing? Are they exactly what you want? Now – after all that has been considered – if you still have a few different choices at your disposal, go ahead and consider cosmetics, aerodynamics, and whether or not it is carbon. The sexiest and lightest bar doesn’t do much for you if it doesn’t fit. Well, it might make your buddies jealous at the group ride, but they won’t be jealous if you can’t control the bike and crash out.


What’s Out There

While I’d like to dedicate an entire article to covering the dimensions of each and every bar out there, it would unfortunately take far too much time to compile all of the information. As previously mentioned, many manufacturers skimp on listing bars bar dimensions, and nobody really agrees on how to measure. Perhaps I’ll have the energy someday.

In lieu of that, your best resource is a highly knowledgeable fitter; hopefully one who has a lot of experience with different base bars, and has a lot of choices in stock. If it is someone who says that base bars are all the same, or they don’t matter “because you don’t spend much time there”, I suggest finding another fitter. Even if only 5% of your race is spent on the base bar, I argue that it is at the most critical points in the race – getting on and off your bike, picking up food and drink at aid stations, and negotiating key corners on the race course. You want to be stable and in-control.

That being said, the company that has the widest array of base bar fit options is likely Profile-Design. A year ago I would have included Syntace with them, but they’ve since discontinued their entire aluminum base bar, and have only the carbon Stratos CX (although in three widths). I’ve personally ridden several of the Profile bars. In the past, the Airwing OS fit the bill on a bike that needed some drop to the base bar, and I’ve more recently used the T2+ bar on a bike that required a flat bar. Both are simple, durable, and get the job done nicely.

Zipp recently expanded their line to include the new Vuka Alumina base bar. I’m happy to report this bar can be taped all the way around the back of the hand grips, but sadly is only available in a single width. The nice thing that Zipp does, however, with both the aluminum bar, and the carbon VukaBull, is allow the user to tailor the reach. Their straight hand grip section has cut lines that allow you to trip up to 15mm. If their width works for you (42cm OTO/40 CTC), it is a great choice. They also have a flat and 40mm drop version of the VukaBull (40mm version pictured above), for those who need drop options.

3T is a relative newcomer in the game, but have expanded nicely to a fairly well-rounded product line. The Ventus has been updated to be called the Ventus II, which now accepts plug-in style brake levers (instead of the thin integrated grips mentioned above). Their various other base bars include the Aura, Mistral, and Brezza. Within this line, you can get widths from 40 to 42cm (CTC), and it appears that you may be able to trim the reach somewhat.

Bontrager’s lineup includes the aforementioned Race X Lite Bullhorn, and also a similar Race X Lite Carbon Aerobar. This is an integrated base bar + clip, and curiously has a shorter drop and reach than the standalone bullhorn (and stands as a better choice for those seeking a shorter distance to their base bar). They also have the simple aluminum Race Bullhorn”, which I’ve personally used and trimmed the reach to fit.

There are more choices out there – Vision Tech, Oval Concepts, Hed, Easton, Ritchey, PRO, and others. Aero bars and base bars are a big purchase. Whether or not you spend a lot doesn’t matter much, but the dimensions of the bars do. It affects your whole experience on the bike. We talk a lot about aero position, which makes sense – it is where we spend the most time. However, don’t ignore that lonely base bar. It is important, and needs your love. Even if that means breaking up, and finding a new one that is more appropriate for your bike fit and taste in music – you will both be better off when the match is right.

  

Articles related to this one
Zipp Vuka Stealth & Vuka Fit
We take a look at the new Zipp Vuka Stealth aerobar and their unique fit tool, called Vuka Fit. If you've ever been intimidated by fitting an integrated bar on your bike, this could change your perspective. 4.12.13
Profile Aero HC System
We review the new aerobar hydration system from Profile-Design. In addition, we flesh out the detailed differences between the different tiers of Profile clip-on bars, and what it means to you. 8.03.13
ENVE SES Aero Bar
There’s a new integrated aerobar on the market for 2014 – the UCI-legal ENVE SES. We take an up-close look at the specs, options, and fit details. 12.06.13
Zipp Vuka Alumina Clip
If you look closely, you'll notice a new motif showing up in aerobar design. The armrest and extension are linked. Zipp has hit the manufacturing cycle about right with its new Vuka Alumina Clip. 4.28.12
The Bike from the bars back—finale
Road testing the 3T Ventus aero bar properly required a bit of trigonometry, a dash of ingenuity, and smidge of creativity, some nerve, and a credit card with room on it. 5.05.08