Upright vs Drop Bars

[Ted Durant]

Jumping off The Charlie Gallop Thread, I thought I'd share some thoughts and data on upright vs drop bars. In that thread I made the observation that wind drag becomes an issue as I get into the 16-20mph range. Today I did a 40 mile ride at an average of 16.8mph, with a nicely low 5mph wind out of the southeast, and modest amounts of hills. So, a bit above that 16mph threshold, and trying to maintain a steady pace all the way around. I found myself riding on the drops for the vast majority of the ride. Anything over 16mph and unless there's a good tailwind I'm likely to be in the drops. Around 16mph I'm often on the brake levers or just behind them. By 12-13mph I'm almost certainly on the tops, with wind drag a non-issue and hill climbing benefitting from more open hip angles. 

So, that's anecdotal.

Now for some data. From November 2016 to November 2017 I commuted to work on a Cheviot, with a typical Cheviot upright position (though I experimented a lot with bars and stems). For commuting I carried a backpack in a front basket. Then, in November 2017, I replaced the Cheviot with a Terraferma Corsa 650B (a very light tubing, very low trail frame) with Noodle bars (the very wide ones, to get around the backpack and basket). Pretty much every ride to work and home was recorded on my bike computer. So, I can take a year's worth of commuting rides on the Cheviot and a year's worth of commuting rides on the Terraferma and compare the data.

I expected, just based on my internal dyno, that my average speed on the Terraferma would be higher than on the Cheviot. Subjectively I felt very slow on the Cheviot. It turns out, though, that the average of average speed is exactly 23.2kph (14.5 mph) for each bike. However, the max average speed for the Terraferma is 27.9kph (17.4mph) vs 26.0kph (16.3mph) for the Cheviot. The 80th percentile, i.e. the speed above which 20% of the rides were ridden, is 25.2kph (15.7mph) for the Terraferma vs 24.8kph (15.5) for the Cheviot.

I think this data supports my anecdotal feel about the 16mph threshold. Over almost 300 rides averaging 14.5mph, the aerodynamics (and the other bike factors ... I might note that tires are pretty much the same on each bike, including studded snows during the winter) don't appear to slow me down, though I don't have any data to address the question of whether I was in fact working harder to maintain that speed. I didn't record when I swapped out the studded tires, so it's possible that factor confounds the analysis. The fact that many more of my faster rides were on the Terraferma, I think, demonstrates the effect of a more aerodynamic position at speeds above 16mph.

Ted Durant

Milwaukee, WI USA

[Jay Lonner]

Reading through these threads makes me realize how slow I am — I generally toodle along at 10-12 mph, and anything over about 14 mph starts to feel downright brisk. I still like drops on longer rides though, not because of any aero gains (which at my speeds I won’t realize) but because of the variety of hand positions on offer. I find myself riding in the drops a lot just because it’s comfortable. The models I favor tend to be very wide, medium flare, shorter reach, and shallow drop — the Crust Towel Rack might be the ur-type of this style. In contrast I’ve tried a number of Bosco/Tosco variants and they are just too upright for me. So even for those not concerned with maximizing performance/efficiency, there are a lot of cool drop bars out there worth consideration just for their comfort/ergonomics.

Jay Lonner

Bellingham, WA

Sent from my Atari 400

On May 15, 2025, at 10:49 AM, Ted Durant <tedd...@gmail.com> wrote:

Jumping off The Charlie Gallop Thread, I thought I'd share some thoughts and data on upright vs drop bars. In that thread I made the observation that wind drag becomes an issue as I get into the 16-20mph range. Today I did a 40 mile ride at an average of 16.8mph, with a nicely low 5mph wind out of the southeast, and modest amounts of hills. So, a bit above that 16mph threshold, and trying to maintain a steady pace all the way around. I found myself riding on the drops for the vast majority of the ride. Anything over 16mph and unless there's a good tailwind I'm likely to be in the drops. Around 16mph I'm often on the brake levers or just behind them. By 12-13mph I'm almost certainly on the tops, with wind drag a non-issue and hill climbing benefitting from more open hip angles. 

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[George Schick]

In my experience over the years one of the most perfectly designed road bars made was the Ritchey BioMax Pro.  It has very shallow drops and instead of the drops having a continuous bend these have a "reverse bend" where the outward curve is normally located.  This makes for a much more comfortable had position when riding on the drops than the usual bend. Further, they have the flattest ramps out to where the brake levers are mounted that I've ever seen allowing for a much more comfortable hand position when riding the brake hoods or further back toward the flats.

Unfortunately, I think they may have been discontinued but I've seen some available on eBay. One reason why they probably lacked popularity among the road bike aficionado is that they were only sold in matt black. Another reason might be that the bend down to the drops is so tight that standard quill stems can't be used.  Finally, many probably thought they were just too homely looking.

[Ted Durant]

On May 15, 2025, at 3:03 PM, George Schick <bhi...@gmail.com> wrote:

In my experience over the years one of the most perfectly designed road bars made was the Ritchey BioMax Pro.  It has very shallow drops and instead of the drops having a continuous bend these have a "reverse bend" where the outward curve is normally located.  

This is definitely a case of everyone having different needs and preferences!

The most perfectly designed road bars, IMO, are the Nitto 177 Noodle, which Grant developed over a few iterations (175, 176, 177). One of the main benefits of drop bars is to allow a variety of positions, ranging from very upright to very low, for those who are lucky to be flexible enough to use that full range. The large-radius bend and slight rise upward in the upper bend make for a few hand positions at the top and a perfect place for the palm behind the brake lever. A very slight cant clears the drops of the tops, and I’ve never had any discomfort from flat drops that are angled so my wrists are neutral.  The large amount of drop (not compared to standards of 50 years ago, but gigantic relative to what’s offered today) means that when I’m in the hooks with my forearms parallel to the ground, I’m as aero as I’m going to get, while the tops are even with the saddle and I can “play piano” up there (as I think Eddy Merckx described?).

[Patrick Moore]

On Thu, May 15, 2025 at 2:29 PM Ted Durant <tedd...@gmail.com> wrote:

On May 15, 2025, at 3:03 PM, George Schick <bhi...@gmail.com> wrote:

In my experience over the years one of the most perfectly designed road bars made was the Ritchey BioMax Pro.  It has very shallow drops and instead of the drops having a continuous bend these have a "reverse bend" where the outward curve is normally located.  

This is definitely a case of everyone having different needs and preferences!

The most perfectly designed road bars, IMO, are the Nitto 177 Noodle, which Grant developed over a few iterations (175, 176, 177).

Nope. The Maes Parallel with ends level with ground — or at least, ends parallel with very slightly upsloping top tube (OK, Bill?). 

For me of course. 

They have long ramps and a relatively shallow drop (125 mm and 115 mm) and while the Noodles were very nice, I’ve found the MPs give me longer ramps and a shallower drop with my preferred lever positions, and I prefer them for pavement and dirt roads and non-tech trails.

On my ride just now I spent 12 or 13 miles in the drops/hooks, continuously except for tight turns and passing other cyclists, elbows slightly bent. Not as comfortable as the ineffably comfortable hoods, but not a strain either.

Agree with the “play the piano” on the tops metaphor. On my road bikes the tops are ~3.5 cm cm below saddle, on the dirt road bike ~0.6 cm below saddle but on a 10 cm instead of 8 cm stems.

Each to his or her own, of course. I’d no more insist that drop bars are better absolutely than other bars than I’d insist that steel is better for frames than other materials, absolutely.

[Patrick Moore]

Riding SW and NE return, winds varying from South to SW to West at 18 to 20, gusts 21-26.

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Alburquerque, Nuevo Mexico, Etats Unis d'Amerique, Orbis Terrarum

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[John Hawrylak, Woodstown NJ]

Ted stated:   " Anything over 16mph and unless there's a good tailwind I'm likely to be in the drops."

I agree and do the same.    I set the top of the bars even or slightly above the saddle, so when I am in the drops I can see ahead without cranning my neck.

Currently using 44cm RH Randonuer bars

John Hawrylak

Woodstown NJ

[Ben Miller]

The stated: "Anything over 16mph and unless there's a good tailwind I'm likely to be in the drops" isn't just Ted, it's backed up by physics. Power needed to overcome air resistance goes as the cube of the relative air velocity. So for an upright rider, the power needed to overcome air resistance at 12 mph is about 50 W. With rolling resistance you should be well below 100 W, which is comfortable to the average rider to maintain. However, at 16 mph the power needed to overcome air resistance has doubled to 100 W and now you're probably needing close to 135W to maintain that speed. Most recreational cyclists average power is somewhere right around that. However, if you assume a good crouched position you can decrease the power needed to overcome air resistance by up to half (our BOBish bikes probably aren't allowing us to achieve that, but any reduction in air resistance becomes extremely useful at this point). And of course, the second half of that statement is "unless there is a good tailwind" which is to the point of relative wind velocity. So if you had a steady 16 mph breeze at your back on level ground, you'd maintain a 32 mph speed with only needing to overcome the modest rolling resistance which grows approx. linearly, so a rather comfortable 60-70 W or so.

I prefer drops mostly for the previously discussed comfort of providing an increased number of hand positions, but for aerodynamics, they're really is no constant between drops and other bars for allowing one to comfortably and safely lower the power needed to maintain speeds above 10 mph. And due to the human body and the physics of road bikes, it just so happens that 16 mph is just about where that inflection point occurs of most of us wanting to go faster. 

[Andy Beichler]

You aren't the only one.  I have never been fast and I never was willing to put in the work to be fast.  People who are fast amaze me, but I am a toodler.  I, too, like drop bars, though.

On Thursday, May 15, 2025 at 2:55:36 PM UTC-4 Jay Lonner wrote:

Reading through these threads makes me realize how slow I am — I generally toodle along at 10-12 mph, and anything over about 14 mph starts to feel downright brisk.

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[Ted Durant]

I decided to use today's ride to add some more data points.

First, great discussion on attributes and preferences around drop bar shapes. On today's ride I thought more about hand comfort. When talking about bike comfort, I like to talk about the three contact points - feet, seat, and hands. As a general rule I'm trying to allocate my weight among those three points, with my hands taking as little as possible. It's pretty simple - the harder your legs are working, the more weight they are supporting and, consequently, your seat and hands are bearing less. For me, at a moderately hard effort, my hands are supporting negative weight, i.e. I'm pulling up on the handlebars in opposition to the force being pushed downward into the pedals. So, much of the time when I'm on the drops my palms aren't pressing into the top of the bar. Riding at a lower level of effort puts more weight into the seat and hands. Hence, wider saddles and swept back bars for a more upright position - more weight on the seat, less on the hands.

Today's ride was a relatively easy one, which for me is defined by breathing rate and how hard I'm working my legs. Total distance just over 40km (25mi), at an average speed of exactly 16mph. Unlike yesterday, today featured a bit more wind. According to the records at our sailing center, wind is SSW this morning, 9-13kts (10-15mph, 17-24kph) on my way out (heading north and a bit west), rising to 11-16kts (13-18mph, 20-30kph) as I came straight south back home. My average speed going out was 26.4kph and my average speed coming back was 25.0kph. It's worth noting that the ride out is quite a bit hillier, curvier, and woodsier (so protected from the wind a bit) than the ride back. Also, I'm leaving out of those stats the top of the triangle, which is relatively flat, going straight east. On the way out I spent most of my time on the tops or the brake hoods. On the way back mostly on the drops or the hoods or a position I didn't mention, my full aero position with forearms on the bar tops and puppy paws over the front of my handlebar bag. That position has two purposes, the obvious aero one and also to take all weight off of my hands. So, somewhat ironically, I use that position most when I'm riding hard and when I'm riding easy. A similar position that I find works well on the Noodle bars is hands on the hoods, wrists and forearms on the handlebar bend behind the hood. Not quite as aero efficient, but close, and also takes weight off the hands.

The final couple of miles of the ride are a flat, straight section of road straight south. I rode for a while on the bar tops, sitting upright, at about 23kph. Then I went into my aero position and, using my finely calibrated leg & lung dyno to keep a steady effort, found my speed went up to about 25kph. Not as big a difference as I thought there would be, but if I was working in zone 2 instead of zone 1, the difference would have been bigger.

Forecast is for ABQ-worthy winds this afternoon. I'm not dedicated enough to the science to want to go back out and add more data points.

Ted Durant

Milwaukee WI USA

[Ted Durant]

On Thursday, May 15, 2025 at 9:35:20 PM UTC-5 Ben Miller wrote:

 it's backed up by physics. Power needed to overcome air resistance goes as the cube of the relative air velocity. 

Thanks for the additional science, Ben! In the Charlie thread I originally put "cube" and then thought, "am I remembering right? sounds like I'm exaggerating...", so changed it to "square". But, cube it is.

I don't have a watt meter so didn't want to bring watts into it, but yeah, the watts measurements line up. I reverse-engineered the Strava watts estimation, based on speed and vertical, then modified it to account for air temperature. I don't know how accurate my resulting model is, but I only use it for making relativity comparisons, so as long as it's internally consistent for me, it suits the purpose.  Strava says my 16mph ride was an average 98 watts. Worth noting that I weigh about 60 kilos.

[John Hawrylak]

The 'cube of the velocity' is due to the 'slow velocity' of a bike rider and a linear decreasing relationship between the Drag Coefficient and Reynolds number (which is proportional to velocity)

The Energy to overcome the Drag is proportional to the Kinetic Energy (KE) and the Drag Coefficient (Cd).  KE is proportional to Velocity squared and Cd is linear with velocity at low Re's, so you end up with v^3.

Either way, squared or cubed, the energy to overcome the wind resistance goes up very fast as velocity increases.  I've noticed the effect at 14 to 16mph, as Ted reported earlier, and that is when I go to drops.

John Hawrylak

Woodstown NJ

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[Ted Durant]

On May 16, 2025, at 9:56 AM, 'John Hawrylak' via RBW Owners Bunch <rbw-owne...@googlegroups.com> wrote:

The 'cube of the velocity' is due to the 'slow velocity' of a bike rider and a linear decreasing relationship between the Drag Coefficient and Reynolds number (which is proportional to velocity)

I’m anticipating some negative comments about going into the weeds on this. I, for one, very much appreciate it! 

Interestingly, I tried to fit v^3 in my model of Strava watts, and v^2 was a significantly better fit. Whether the Strava estimate is good is a different question. It doesn’t account for wind speed or air temperature, so we know it’s missing a couple of marginal effects.

Super interesting to me that people are converging, analytically and anecdotally, on 16mph (25kph) as something of a magic wall.

[Toshi Takeuchi]

Energy is mv^2 so definitely square of velocity 

Drag from wind may be v^3 but I didn’t learn about that.

On my longer rando rides I target 15 mph on flats when I’m by myself. Not too hard, but not too easy. Wind is the wildcard. Same effort can net me 25 mph or 6 mph (granny gear on flat ground, ouch!).

Toshi

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[Piaw Na]

There's a chart here that describes the power required to ride at any given speed for various positions on a bike (aerobars, drops, hoods, tops, and standing): https://ridefar.info/bike/cycling-speed/air-resistance-cyclist/

You can see that the standing position is clearly a lot worse than the others, and that the article claims that the difference between the tops and the drops is about 1kph or 0.6mph. That doesn't sound like a lot, at 15mph 70% your power is going into overcoming air resistance. (https://maa.org/math-values/2018-7-19-devlins-angle-post-1-sf48y-x6edp-l56an/#:~:text=What%20the%20math%20tells%20you,accounting%20for%20the%20other%20half).)

I guess what this tells me is that I should try lowering the handlebars on my son's Roadini.

[George Schick]

Interesting discussion, stats, and equations here.  I realize that most of it aimed at things like bar types, bar heights, and rider positions when encountering wind resistance at various speed thresholds.  Two things that I have not noticed yet (and these may get me kicked off the discussion thread): 1) tire width and pressure (therefore rolling resistance) and 2) "wind breaks."  The first of these might be kind of moot since the rider would be starting a ride with the same tires and pressures as he/she encounters headwinds.  So...if pressures and widths (maybe throw in tire weight as a wild card) make some difference a tail/head wind ride differential would be represented in a ratio similar to what's been discussed previously only at more optimal levels? "Wind breaks" occur in pace lines.  The poor chap at the front bears the strain of a headwind and is solely responsible for keep the line at more or less the same speed when it's his or her turn to pull.  Meanwhile, everyone else enjoys an easier effort on down the line EXCEPT for those who are riding a more upright position - they'll catch some of the wind, too, and can't do anything about it (although those behind will enjoy a bit of "double break").

[Ted Durant]

On May 16, 2025, at 12:33 PM, George Schick <bhi...@gmail.com> wrote:

 Two things that I have not noticed yet (and these may get me kicked off the discussion thread): 1) tire width and pressure (therefore rolling resistance)

I noted in my original post that between the two bikes I used essentially the same tires. In the winter that would have been studded snow tires, which are significantly slower (require more power) than the Compass/Rene Herse tires I ride other times of year.  My data covered exactly 1 year with each bike, so the tires aren’t a factor unless I had the snow tires on one bike for a significantly different amount of time. I generally keep my tires within a reasonable range of pressure that wouldn’t contribute to differences.

and 2) "wind breaks.”  

My commuting and the two rides I’ve described were all solo. So, no drafting effect.

The tables and math that have been referenced also assume a single rider. It’s worth noting that the lead rider in a group (n>=2) benefits from the rider(s) behind, if the next rider stays close enough to interrupt the closing of the air at the back of the lead rider. I think that’s been measured at around a 10% reduction in air resistance, compared to a 50% reduction for the rider behind. Don’t quote me on that, those numbers are from memory.

It’s not just people sitting up that have a reduced benefit of drafting. Tall people also pay a penalty. At 167cm and 60kg, people grumble about not getting much of draft behind me. I say all’s fair because I have way less inertia working in my favor. Tall, light, and upright would be an especially bad combo in a headwind.

[Ben Miller]

"Energy is mv^2 so definitely square of velocity" that is your kinetic energy, which is important for determining acceleration (i.e. braking, speeding up), but not relevant to the power needed to maintain a constant velocity.

"Drag from wind may be v^3 but I didn’t learn about that." It's not, but it's important to define a few terms here: 

1. Force is the thing needed to accelerate a given mass : F = m * a [This is measured in pounds/Newtons]
2. Energy (or work) is a force over a certain distance: W = F * d [This is measured in Joules/kilocalories] 
3. Power is a work done over a certain period of time: P = W / t = F * d/t = F * v [This is measured in Watts]

The "drag from wind" is a force and it is a function of the square of the velocity (F_drag = C_drag * A * v^2). But the Power needed to overcome this drag force is that force multiplied by the velocity again (as above P = F *  v: So P_drag = F_drag * v = C_drag * A * v^3). So again, the power needed to overcome air resistance goes by the velocity cubed. 

You can change your coeffecient of drag (C_drag) and your frontal area (A) by crouching on the bike. Drop bars are hands down the best way to do this. (Pun intended :)

The full equation for power needed over come air, slope, and rolling resistance looks something like this: P_total =  C_drag * A *(v_ground + v_wind)^2 + m * g * (C_slope * C_rolling)] * v. To quote David Gordon Wilson in the 3rd edition of Bicycling Science: "This was known a century ago." I'll raise him a bit; the physics was known since at least Euler and Newton's time, so probably closer to three centuries ago. 

[Ben Miller]

"Two things that I have not noticed yet (and these may get me kicked off the discussion thread): 1) tire width and pressure (therefore rolling resistance)" Definitely mentioned this in my first post. Again, the important thing isn't the exact value of your bike/human rolling resistance, it's that this only increases linearly with velocity whereas air resistance changes with the cube. 

I think the biggest thing that we've discovered (or rediscovered??) in bicycling science over the last two decades is that rolling resistance is not just tire pressure (and very little to do with tire width). Rolling resistance is really the resistance of the entire bicycle/human machine to continue rolling. This is effected by design of the tire, tread, surface conditions, suspension, "planing" etc. Some of these things are fixed for a given bike build, while others change continuously throughout your ride (in the real world). However, disregarding things like Fat bike tires and poorly tuned MTB suspension, there appears to be a pretty narrow range of how much this varies for bicycles. If we go back to the above equation for total power needed to maintain a constant velocity, the C_slope is changing much much more throughout real world riding (except my those rides in Florida :) than C_rolling , in general. Or, to think of it another way, if P_total = P_air + P_slope + P_rolling, than for a given rider on a ride with even moderate elevation changes, P_air is going to vary the most, then P_slope, then P_rolling. Infact, you could probably assume P_rolling as constant and still have a pretty good estimate of the average power needed on that ride. 

I like to think of rolling resistance as a fixed cost for a given bike. It's something you can feel inherently in the bike (with care and consideration, because sensations can deceive you here) and why we call certain bikes "fast" or "slow". Course and where you ride determine your "slope" costs. And your aerodynamic costs are something you can actively vary depending on your instantaneous ride conditions. As Ted astutely observed, 16 mph tends to be speed at which that begins to pay off.

[George Schick]

Ben, thanks for the input.  But I'm still fixated a bit on tire weight, etc.  Doesn't centrifugal force come into play to some extent, i.e, F = m v² / r? IOW, a wide tire (let's say 40-50cm tire that weighs in the area of 300-400 grams) mounted on a wide enough rim to accommodate it (therefore heavier) represent a mass out at the rim that might be fine while rolling along in a tail wind or drafting in a pace line, but constantly more effort when riding solo into a stiff wind than say someone with a much narrower and lighter tire inflated to higher pressures would encounter?

[Ted Durant]

On May 16, 2025, at 1:31 PM, Ben Miller <ben.l....@gmail.com> wrote:

This is effected by design of the tire, tread, surface conditions, suspension, "planing" etc. 

This brings up an interesting and, for me, surprising aspect of the data comparison I made in my original post. The Cheviot is definitely not a “planing” (terrible use of that word, I prefer “swinging”) frame. Stiff as a big, steel I-beam in my experience. The Terraferma is a Jan-approved noodle, skinny tubes, thin walls. I’m light and weak, but I can pretty easily deflect the bottom bracket enough to make the chain hit the front derailer.

Without thinking too hard about it, at my commuting speeds, “bike drag” (the whole bike/human rolling resistance bag of stuff) should be more of a factor, relative to wind, than at my recreational riding speeds. So, the difference in position doesn’t make a big difference at the speed, but surely the springier bike would be faster. Thinking more about it, though, Jan has (mostly, not always) been clear that what he calls “planing” is an effect that shows up in high-effort situations, like climbing at high speeds. I’ve seen finite element analysis that confirms that notion - for a given frame, there is a level of effort at which the “swing” kicks in. My commuting level of effort is below that level for both frames. My perception of slowness/stiffness/responsiveness/swing really only happens at initial acceleration from a stop or when giving a little extra effort to climb the tiny hills on my route, i.e. for a tiny percentage of the total time riding. Those perceptions certainly contribute to how I feel about riding each bike, but they don't show up in my data on average speeds.

Back to upright vs drop bars … that whole bag of stuff that amounts to bike/human rolling resistance includes the leverage and spring characteristics of handlebars and hand position.

And, speaking of that, and Bicycling Science … Gary Boulanger (Riv employee who worked at Waterford during the epoch of Heron) and I went for a ride one day. As we left Thiensville, climbing the 8% bugger of a hill going west, we came upon a somewhat scruffy, not terribly trim guy riding a Columbia 3-speed. He casually matched our speed and chatted breezily with us as we climbed the hill. Not a bit of windedness to him despite the effort. Introduced himself as Jim Papadapoulos, a major contributor to much of what we know about bicycling science.

Ted Durant - still using the Second Edition, but those equations haven’t changed :-)

Milwaukee WI USA

[Ben Miller]

George, the above equation is looking at only maintaining a constant velocity, so by definition the force is equal to 0. Since bicycles can accelerate fairly rapidly and the bike/human machine is fairly lightweight (relatively speaking), the energy to accelerate the bike over the course of the ride is small and can be ignored without changing the average power calculation too much. However, it's not nothing! So lets look at it: First, when talking about accelerations, it's generally easier to think about work/energy as opposed to the forces them themselves. Rotational energy is pretty similar to kinetic energy in that it is one half of the moment of inertia times the angular velocity: E_rot = 1/2 * I * w^2. For a bicycle wheel, this is approximately equal to this: E_rot = 1/(8*pi^2) * m_tire+rim * v^2 (note that it does not depend on the radius of the wheel!). So 700c/29er tires can easily vary from 200 to 800 g or more, or a factor of 4! This seems like a big change in our rotational energy need to get the tire up to speed! And since you have 2 of them it is compounded! Indeed, the energy needed to get a bikes wheels accelerated from stop to a certain velocity can easily change by a factor of eight due to the tires alone. Rims also matter, but they just don't vary as much was tire weight (usually less than a factor of 2)

But all that rotational energy is very small compared to the kinetic energy of the bike. Lets say you have heavy tires like 2.4" MTB  (800 g) on heavy rims (700g). The total rotational energy of those at 16 mph is ~2 J. But if the bike/human weighs 95 kg, the kinetic energy of that is 2000 J or one thousand times more! Instinctively we all know this. But a 29er MTB with 2.3 tires on a bike stand and spin them up, grabbing the brakes stops them nearly instantly. But Get on that MTB and get up to speed: stopping now takes considerably longer.

TLDR; although everyone talks about rotational weight of the bicycle mattering more, in reality it does not. In particular, I think carbon rims entirely unnecessary.

[Ted Durant]

On May 16, 2025, at 2:44 PM, Ben Miller <ben.l....@gmail.com> wrote:

TLDR; although everyone talks about rotational weight of the bicycle mattering more, in reality it does not. In particular, I think carbon rims entirely unnecessary.

Great post, Ben!

I have a less physics-oriented and more practical take on this. In a steady-state, inertia is your friend. If you are accelerating or decelerating, it’s not. So, over the course of, say, a leisurely doodle around the lakes, stopping for a picnic, never accelerating hard, tire weight probably doesn’t mean anything to you (though having to stop and repair a flat might!). Over the course of a 200km brevet, maybe on some less than perfect roads, all those little bumps add up and if the tire is absorbing those bumps with low hysteresis instead of accelerating your 95kg of mass upward, those tires will save a lot of energy, but lighter rims might make you a DNF if they fail. If you’re commuting in an urban area with lots of stops signs/lights, and you’re always trying to accelerate quickly back up to traffic flow speed, you’ll feel the extra effort of accelerating heavy wheels. If you’re trying to out-accelerate Jasper Disaster at the end of a 200km stage, you’ll definitely want those super light rims and tires. 

So, yeah, for me, the 540g rims on my brevet bike with 32mm supple tires have been great. Steady-state for hundreds of km at a time.

[Bill Lindsay]

It's always interesting to see what people want to talk about vs. what things they don't care to talk about.  The subject of the thread is Upright vs. Drop Bars.  The Original Poster in their Original Post presented their own perception: that their drop-bar Jan Heine approved "planing" bike feels a lot faster than their Cheviot.  The Original Poster then presented data, collected over hundreds of rides that proved their perception was totally wrong, and in fact the two bikes are WITHIN ONE MILE PER HOUR from one another.  To me, that's a bombshell, and I was waiting to see people taking sides around that bombshell...but nothing.  I figured there would be some drop bar zealots insisting that drop bar bikes are >5MPH faster or more, or upright bar zealots celebrating "See!? Our upright bikes are just as fast as your road bike, and while you grimly contemplate the pavement "in the hooks", I'm smiling and enjoying the view!"  Instead the three has meandered into the math of speed (which is a perfectly fine thing to talk about). 

If the data presented by the Original Poster is representative of the larger truth as it applies to essentially ALL of us UN-racers, then when it comes to speed, it does not matter one bit what bike you ride, provided you like it and it fits.  Ride the bike you like.  Like it because you like it.  If you stop liking it, change it or get another bike.  If you decide you want another bike to like, buy one.  If you want to go faster on a bike you already like, pedal harder.  

Maybe the lack of anybody pushing back on the OP data means that this is what everybody already does or already knows: there is no such thing as a fast bike for UN-racers.  Your "GOFAST" is not called that because it objectively goes fast.  It's called that because it looks fast and it makes you happy that you feel like a fast rider when you ride it.  The speed is in the rider, so ride the bike you like.  If you want to be a faster rider, become a faster rider, because the bike won't get you there.  Those of you who are fast are not fast because of your bike; you are fast because of you.  

Bill Lindsay

El Cerrito, CA

[Ted Durant]

On May 16, 2025, at 4:09 PM, Bill Lindsay <tape...@gmail.com> wrote:

If the data presented by the Original Poster is representative of the larger truth as it applies to essentially ALL of us UN-racers, then when it comes to speed, it does not matter one bit what bike you ride, provided you like it and it fits. 

Close, but the data only applies to riding at my commuting speed, which is a few mph slower than my recreational riding speed, and now commuting represents zero percent of my riding time.

The real point of the thread is that 16mph seems to be a real threshold, above which aerodynamics become significant, below which you can blow them off.

Ted Durant, the Original Poster

Milwaukee, WI USA

[Bill Lindsay]

Ted I think we're agreeing.  I assert that most UN-racers spend the majority of their time cycling at speeds below 16MPH.  Those of you who spend the majority of your time riding MUCH faster than 16MPH are not UN-racers in my book.  I definitely spend the majority of my time below 16MPH.  I spend the entirety of my time riding the bike I feel like riding.  

Bill Lindsay

El Cerrito, CA

[George Schick]

Plus what Ted says we have on other threads who lament that they're using too much effort on their supposedly correctly set up "road bikes" to compete with others in pace line club rides. Seems like Ted and several others have suggested in this particular thread is to recommend a different handlebar/height configuration in order to do be able to do so. 

[Bill Lindsay]

Ted's data is saying pretty clearly that if you are riding 16MPH or slower on a "road bike", that there is no other bike that's going to make you ride a lot faster than 16MPH with your existing engine.  That's what Ted's data says, and I cannot dispute or disprove that data.  For those people who think a bike will make them faster, it's back to the two canonical quotes.  I'll paraphrase both from memory:

Greg Lemond:  "training never makes it easier..you just go faster"

Eddy Merckx:  "don't ride upgrades.  Ride up grades"

Bill Lindsay

El Cerrito, CA

[Ted Durant]

On May 16, 2025, at 4:19 PM, Bill Lindsay <tape...@gmail.com> wrote:

Ted I think we're agreeing.  I assert that most UN-racers spend the majority of their time cycling at speeds below 16MPH.  Those of you who spend the majority of your time riding MUCH faster than 16MPH are not UN-racers in my book.  I definitely spend the majority of my time below 16MPH.  I spend the entirety of my time riding the bike I feel like riding.  

LOL - my big biking goals for the last few years - ride a lot, enjoy it all.

I try to spend time above 16mph, especially on those rides where I am trying to make myself stronger. I consider myself an un-racer, but I will admit to racing against my former self. Maybe that makes me an un-un-racer, I don’t know. Of course, Grant would point out that blowing off aerodynamics would allow me to get stronger just the same, I’d just be covering fewer kms. True enough, but, to your point, my bikes are set up in a way that when I get on them I feel like riding and I still feel like riding in a wide range of wind and road conditions.

Actually, I’m pretty sure Grant would say a bike is a terrible gym and shouldn’t be used for exercise, especially to make yourself stronger. It’s a POV I understand, and it’s why I try to do 3 sessions of resistance/weight work a week. But I feel my physical best when I’m on one of my bikes riding around 16-18mph.

[Ben Miller]

I know y'all are probably sick of me:) But here's a sort of the breakdown of things I said above:

1. Power req'ed to overcome air resistance and maintain 16 mph: 100 W
2. Power req'ed to overcome rolling resistance and maintain 16 mph: 35 W
3. Power req'ed to smoothly accelerate up to 16 mph over 30 sec: 75 W
4. Power req'ed to smoothly accelerate your wheels to 16 mph over 30 seconds: 0.05 W

(Approximate values for a 95 kg human+bike, with C_drag *A of .5 m^2 , C_rolling of 0.005, and 1.5 kg per each rim/tire combo. C_drag*A and C_rolling are approximately average values for the majority of cyclists/bikes per Bicycling Science 3rd Edition. 30 secs to 16 mph is a pretty reasonably fast acceleration for a recreational cyclist)

It just can not be emphasized enough that effect of rotational mass of the bicycle does not matter in terms of overall power/energy needed. (Jan Heine claims it effects handling... and it certainly does to an extent, but even there I think that claim is overstated)

But Ted is still wondering if you want those lightweight wheels to out accelerate Jasper for the stage win, lets say Jasper Disaster is riding really heavy 1.5 kg rim/tire as above. And you have super light weight .5 kg rim/tires. The power savings advantage you'd have is .04 W for getting the tires up to speed and .8 W for the total kinetic energy. Okay, okay, but that was for the slow acceleration of 30 s, what about faster accelerations? The thing is the ratio of those are always the same, so losing overall weight is going to have a larger impact than the rotational side of it. You do get the double bonus with rotational weight in that is overall + rotational, but that power saving in rotational is generally x20 less even in the extreme case. Maybe that matters in sprinting??? Call me skeptical. But for us non-racers, no way. 

As for commuting around and lots of stop/starts, it still isn't going to impact your average power/total req'ed energy much, but what tires (physical exhaustion, not the rubber kind) humans out isn't so much average power, but peak power (which in the above example is x1.5 greater; most everyone's peak sustained power is x1.5 higher than there average; regardless of overall power output). Consistently hitting peak power is going to tire you out and make the ride feel much harder than it would be otherwise. Again, it's really got nothing to do with your wheels. 

And finally, I definitely agree with Bill: the bike hardly matters much in this at all. It's subtle stated in all of what I said. The main source of air resistance is you and even on an upright Bosco'ed bar you can crouch and reduce that. The main source of weight is you and you bike hardly changes that. The range of coefficients of rolling resistance is very narrow in general and how you ride probably effects this more than which bike or at least nearly as much. Performance of a bike lies within such a narrow range for modern bikes and it really is you and how you ride that bike determines the "bike's performance." Bike styles/builds is really got more to do with comfort, safety, and preference. Ride the tires that are the most comfortable, provide the amount of traction best suited for your riding style, and a cockpit that is the safest and most comfortable for you and you're doing just fine. 

Phew, all that said: I need to go out for a ride :) Thanks for indulging my overly equation-laden posts on the physics of bicycling! I won't be thinking of any of it while I ride my bike though :)

[Piaw Na(藍俊彪)]

On Fri, May 16, 2025 at 2:35 PM Bill Lindsay <tape...@gmail.com> wrote:

Greg Lemond:  "training never makes it easier..you just go faster"

Eddy Merckx:  "don't ride upgrades.  Ride up grades"

The internet loves to mis-attribute the latter quote to Eddy Merckx, but it came originally from my friend David Keppel (http://pardo.net/bike/pic/fail-017/index.html). 

[Bill Lindsay]

That's sensational knowledge.  Unless somebody can prove that phrase being used before 1987, your friends claim would hold.  

BL in EC

[Bill Lindsay]

"It just can not be emphasized enough that effect of rotational mass of the bicycle does not matter in terms of overall power/energy needed. (Jan Heine claims it effects handling... and it certainly does to an extent, but even there I think that claim is overstated)"

Jan (and others) will also sometimes backtrack to other justifications for their feather light wheels "It's just more fun to throw the bike around in a sprint with light wheels".  Others will hand-wavily talk about how every single pedal stroke includes a power phase during which you accelerate a little, plus a rest phase where you decelerate a little.  These tens of thousands of "micro-accelerations" all add up and make those light wheels more important.  There's no basis for any of that.  Buy those $1500 super light wheels because you feel like it, not because speed demands it of you.  :)

Bill Lindsay

El Cerrito, CA

[Ted Durant]

On May 18, 2025, at 8:15 AM, Bill Lindsay <tape...@gmail.com> wrote:

Buy those $1500 super light wheels because you feel like it, not because speed demands it of you.  :)

Time for a new (another?) thread on wheel weight :-)

[Patrick Moore]

Well, not so close, if you regularly ride into 20 or 25 mph headwinds. If you maintain any forward momentum at all into a 20+ mph headwind, the type of bike, or at least the shape, width, and position of the bar, makes a big difference.

Patrick “non-non-non-non racer” Moore, who finds a low tucked position essential to having riding fun, very slowly, in windy ABQ, NM.

[Bill Lindsay]

I've got three questions:

1. Who ever said sitting bolt upright is the winning strategy to beat headwinds?

2. What is it about drop handlebars that forces the rider to assume the most aerodynamic riding position possible on that bike?

3. What is it about upright handlebars that prevents the rider from assuming the most aerodynamic riding position possible on that bike?  

My preemptive answers are: Nobody, nothing, and nothing.  

Ted's 16MPH threshold idea is that when he's moving through the air at less than 16MPH it makes very little difference.  You riding 12MPH into a 20MPH headwind is you moving through the air at 32MPH, which is Ted's "drop bar zone".  

Bill Lindsay

El Cerrito, CA

[Patrick Moore]

On Sun, May 18, 2025 at 5:29 PM Bill Lindsay <tape...@gmail.com> wrote:

I've got three questions:

1. Who ever said sitting bolt upright is the winning strategy to beat headwinds? Not me.

2. What is it about drop handlebars that forces the rider to assume the most aerodynamic riding position possible on that bike? I dunno.

3. What is it about upright handlebars that prevents the rider from assuming the most aerodynamic riding position possible on that bike?  Shape; but there’s the comfort factor.

My preemptive answers are: Nobody, nothing, and nothing.  See above.

Ted's 16MPH threshold idea is that when he's moving through the air at less than 16MPH it makes very little difference.  You riding 12MPH into a 20MPH headwind is you moving through the air at 32MPH, which is Ted's "drop bar zone”.  Exactly.

Bill Lindsay

El Cerrito, CA

On Sunday, May 18, 2025 at 3:23:04 PM UTC-7 Patrick Moore wrote:

Well, not so close, if you regularly ride into 20 or 25 mph headwinds. If you maintain any forward momentum at all into a 20+ mph headwind, the type of bike, or at least the shape, width, and position of the bar, makes a big difference.

Patrick “non-non-non-non racer” Moore, who finds a low tucked position essential to having riding fun, very slowly, in windy ABQ, NM.

On Fri, May 16, 2025 at 3:14 PM Ted Durant <tedd...@gmail.com> wrote:

On May 16, 2025, at 4:09 PM, Bill Lindsay <tape...@gmail.com> wrote:

If the data presented by the Original Poster is representative of the larger truth as it applies to essentially ALL of us UN-racers, then when it comes to speed, it does not matter one bit what bike you ride, provided you like it and it fits. 

Close, but the data only applies to riding at my commuting speed, which is a few mph slower than my recreational riding speed, and now commuting represents zero percent of my riding time.

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[Bill Lindsay]

OK, well here's some news, then:

There are some cyclists who sometimes ride a bicycle with drop bars, but rarely ride in the hooks.  Some cyclists spend nearly all the time on the hoods or the ramps, even the tops.  I think you would say their flexibility is lacking, and you may be true -AND/OR- their bars are too low for their current bodies, and that may also be true.  

There are handlebars more aerodynamic than drop bars (called aero bars).  The typical setup forces the rider into two very aero positions.  Either in the hooks where the brake levers are, low but also medium width, like in the hooks on a narrow drop bar -OR- even more aero by getting even more narrow, with elbows in and hands forward.  Maybe you should try some and see if it's even better for you!

There are some cyclists who sometimes ride a bicycle with upright bars, and sometimes decide to crouch down and get low for aerodynamics and/or for power.  Here's photographic proof.  It is a digital photograph of a film photograph taken by Grant Petersen of a cyclist riding up a pitch on Shell Ridge in the foothills of Mount Diablo.  The rider is on an Atlantis with a huge stack, plus a fairly tall stem and a low rise upright handlebar (the Choco).  The rider, who is accustomed to a traditional flat back power position during climbing has elected to grab the Choco bar in the center hooks, bent elbows, etc.:

https://flickr.com/photos/45758191@N04/54527876217/in/dateposted/

(Yes, the cyclist is me, with a beard I rarely grow out, and a backwards Red Sox baseball cap).  My stable has four bikes with upright bars, and none of them prevent me from getting low and aero or low and powerful when I elect to get there.  

I learned something new today about Rob English, a legendary bicycle builder who knows more than most about aerodynamics.  What I learned is that he commutes 45km each way to his workshop, and he does a lot of his commuting in a Velomobile.  If there were only a cyclist in windy Albuquerque, who cared about having fun defeating headwinds and who sincerely cared about aerodynamics.  That hypothetical cyclist might have a hoot in a Velomobile.  I've been glancing their website and they claim that the leg-power it takes to ride steadily at 50kph (over 30MPH) is 160 Watts!  That's bonkers.  

Bill Lindsay

El Cerrito, CA

[Ted Durant]

On Sunday, May 18, 2025 at 7:29:38 PM UTC-5 Bill Lindsay wrote:

OK, well here's some news, then:

The "pro tip" advice is to set your handlebar height so you ride most on your brake hoods, which should be mounted on narrow bars and angled inward to make the position even more aero. The hooks are for sprinting, and most "pro" bars have vestigial drops that don't appear to me to even have room for my small hands. 

I'm not going to speak for "some cyclists", just for myself. I set my handlebar tops close to even with the saddle top and use relatively deep drop bars. I can and do ride for hours at a time on the drops of my bars. I also, on most of my bikes, have the more aero position of putting forearms on the tops and hands over the top of the handlebar bag. I've been feeling validated about my setup as I've watched pro riders and triathletes raise their aero bars higher and higher in the last few years. I can't spend a full hour in that position (well, I could if I needed to), but it's a great option when going harder into the wind or when going slowly and I want to take weight off my hands or open up a snack that I just pulled out of that bag.

I spent a year and a pile of money on bars and stems trying to find an upright bar setup that allowed for the same range of motion and comfort as a Noodle bar. Sure, I could achieve a lower back position, but never in a way that was comfortable for more than a few minutes.  Upright bars have been great for the kind of riding I do on my Hubbuhubbuh. If those bikes and bars had been available back when I was making regular trips to Walnut Creek, I'm sure that's what we'd have happily ridden all over the hills. It just didn't work out for me on a single bike for the kind of riding I do most of the time.

YMMAPWV.

[Corwin Zechar]

Hi Ben -

Your data tracks closely with my experience. What never fails to amaze me is I can be working relatively hard to maintain some speed; could be in the presence of a headwind, a tailwind or no wind - and in my most aerodynamically efficient posture - I am frequently passed by someone on a recumbent or better yet, a recumbent trike. The person on the recumbent trike is invariably having a much easier time maintaining their more sprightly pace.

It always brings home the ever present contribution of aerodynamic drag to my cycling. Not that I begrudge those on recumbent bikes/trikes, etc. their reduced coefficient of drag; I ride bike I want to ride - moustache'd, albastache'd or drop bar'ed.

Regards,

Corwin

[Corwin Zechar]

By the way - when I get passed by someone on a recumbent - they are usually moving about 1 or 2 mph faster. Not a whole lot faster. Just a lot less effort.

CZ

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