Aero tips and tricks

Here’s a list of simple tips and tricks you can use to help yourself go faster on the bike for any road discipline. (TT, Road Gravel). I’ll add links to good articles, reviews and testing in the thread below.

Gear:

  • Wheels: Deeper is generally faster depending on the brand. Top wheels include HED, Zipp, Enve, DT Swiss and others. For flatter road riding a quality 60-65mm wheel tests quickly and is stable in wind. For hillier country a 40-50mm wheel generally provides a great balance of aero and climbing ability. Things to consider with wheels including handling in windy conditions, tubeless compatibility, rim width, spoke count (lower is generally faster)
  • Tires: For road riding nothing really beats the GP5000 clincher and TR. Tire sizing for the front wheel is critical. For a road wheel with a rim width 17-21mm width the 23-25mm tire is well suited. In the rear running a slightly larger tire (28mm) will give you rolling resistance savings and won’t have an impact on aerodynamics. For TT’ing the top riders are all going tubeless now. I just picked up a set of GP5000 Grand Prix TDF TT tires. Using a top tire can save you 10 watts depending on the comparison tire. Check out bicycle rolling resistance . Com for tons of great information on tires.
  • Handlebars: Narrower is faster. A 38cm bar will test 10 watts faster with rider onboard than a 42cm bar at 40kmh. When selecting a bar measure across your shoulder width from the bony protuberance on each side. You can go comfortably 2cm narrower than this measurement for your bars. Tipping the hoods slightly inwards will also help aero in the “flat on the hood position”
  • Pedals: Speedplay aero generally test the fastest but are the biggest pain to setup. Personally here I’d use whatever you are most comfortable with. Pedals with lower stack height are generally fastest as they move your whole body lower on the bike by a few mm.

Clothing and Helmets:
Huge gains can be made here, upwards of 20-30 watts versus flappy kit

  • Helmet: A road aero helmet can be 9-11 watts faster at 40kmh than a regular entry level or highly ventilated helmet. There are several top brands but I’ve found good success with Specialized Evade II. The version III of this helmet was just released which increased ventilation at no expense to watts saved. There are other great helmets out there too from Giro, Bontrager etc. TT Helmets are VERY individual specific. There are several that seem to test consistently fast across all rider types. This include the HJC Adwatt, Specialized TT, Giro Aerohead.

  • Kit: Skinsuits offer the best bang for your buck and come in a range of prices. Some are custom made and over $2K others are off the shelf and can be bought for a couple of hundred dollars. Our LG Faction skinsuits test very well and have two pockets available to store your gear. For TT Drag 2 zero, Endura, Velotec, Castelli all test well.

  • Shoes and Shoe Covers: Shoes without boa’s or complicated strap systems test fastest. (Lace or Velcro strap systems. Shoe covers work but are expensive and quite fragile. Castelli sells a very fast integrated shoe cover and aero sock. Velotoze also sells a couple of great versions of shoe covers

  • Socks: Aero socks provide decent aero gains as well. (More than shoe covers usually). There are a number of good offerings from Castelli, Aerocoach, Drag2Zero etc.

Pacing: (General road riding and TTs)

  • Starting: Don’t sprint flat out from the start and for the first 2-3 minutes consciously pace yourself slightly lower than what “feels” right. You are going off with adrenaline and it’s easy to go out too hard. I target ~95% of race pace target for the first three minutes unless there’s an uphill at the start of the course. In that case I do a harder warmup so that I’m primed to hit the hill harder
  • Corners: Enter smoothly into corners and accelerate out of them and back up to speed as fast/smoothly as you can. The goal is to minimize your time at lower speeds
  • Hills: How you approach hills depends on the hill type (short and sharp, long and grinding). For short punchy climbs you can go into the red for a short time to get up and over. For a longer hill target to go no more than 10% over your target power for a longer TT. Similar to corners your goal is to get back up to speed smoothly and as quickly as possible over the top
  • Headwind versus Tailwind: This is often difficult to pace both from a pedal stroke inertia perspective as well as power target. In a headwind it’s generally recommended to target around 103% of your target power and ~97% on the return. For out and back courses it’s generally ideal if the headwind is on the way out and the tailwind on the return. Racers tend to go out too hot and this wind direction is more forgiving. For me personally with headwind return I try to target an even split power wise as I tend to naturally make more power at higher speeds with a tailwind. (This comes down to muscle fibre composition and pedal stroke mechanics)

Position:

  • Tops versus Drops versus Hoods: Flat on the hoods often fastest, next is the drops and finally the tops
  • Low and long is faster than high and tall
  • When aiming to go fast target relaxing and sinking your head down between your shoulder blades and squeezing your shoulder blades together. This can reduce your frontal area by centimetres and make a big difference to how aero you are on the bike.

Hope this helps!
Cheers,
Chris

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Whoa…this is gonna be a rabbit hole. Let’s go!

In addition to @ChrisP 's excellent advice.

Let’s start with aero bottles. I was in McPhails today and Mike was building up the newest, craziest P5 I have ever seen. It had a single…~400ml aero water bottle on the down tube. It kind of looked like an ELITE Crono CX? I asked him to look into getting one.

Andrew Lambert has a couple of Crono CX’s on his gravel bike. The fact that he holds 40kph on a gravel bike while riding away from Group 1 has us all thinking.

I also remember Gaelen, many years ago reaching over and moving my water bottle from my seat tube to my down tube…and said…I just saved you 5 watts. And so when I need to be extra-speedy fast, like on a long TT…I’ll remove all bottle cages and install 1 at the lowest position on the downtube and put in a small, skinny water bottle. Perhaps it’s all mental…but it feels faster.

That’s bottles and cages.


I wore a skin-suit yesterday for the final Thursday Middlebrook madness…to everyone’s great horror.

But…it had long sleeves, and very tight fit around the neck and clavicle to shoulder area…it was smooth around my fat hips. And I have to tell you…it felt “faster” than my regular kit doing 55kph on Middlebrook.

Or more “slippery” in the wind. I felt I could hold a faster speed with fewer watts. And I closed and coasted more in the draft. Dunno? Anecdotal. But, if I HAD to go faster…I’d where the skin suit again even if it were to save 5 extra watts for 30 seconds in the final 500M of Middlebrook.


That evade helmet.

I have never played in a wind tunnel. But, I do play aero games on the bike…tilting and moving my head up and down until I can feel the airstream along my back. As you tilt you head you can move the tail of the airstream from middle back…and as @ChrisP says…lower your head, pinch your shoulders and squeeze…and the airflow moves down your back and off your ass. And you can watch the speed go up .1 to .3 kph. And actually move your speed up and down on the Garmin, at the same power and cadence by just tilting your head. That is always above 40kph. But, you know precisely where your head has to be to get that air stream in the right place precisely when leading out or breaking away at 50kph. I suspect people can see it when I lower my head. It’s go time.

BTW…this is another thing that frustrates me about Zwift. None of these aero tricks work in the virtual world. I ride Belgian style or in the drops 90% of the time that I am on a bike. Allows you to be lower, use fewer watts and slip by anyone who rides on the hoods. Can’t do that in Zwift. Grrrr!


Aero Wheels.

Easton EA 55 tubs.

60-ish seems to be a magical sweet spot.

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Aero bike parts and design.

I once read how flat top road bars…like the ones on the S5…can save 8 watts above 40-50kph. @ChrisP you had the same bike, same year as me.

All the little aero treatments on that S5 from curved seat tube around the rear wheel to the “aero shoulders” of the seat stays protecting the rear brake calipers…seem to cumulatively provide a 1-2kph average speed increase for me the day I got it and moved away from my R3. The R3 is an outrageously wicked bike. But, it is 1-2kph slower than the S5 above 40kph for me. Again…no wind tunnel data…but I’ve ridden them many times and that seems to be the perceived case that the S5 is significantly faster when you step on the gas above 40kph.


Cumulative Margin Gains.

All of the above is about little gains. 3 watts, 11 watts, 5 watts, 2 watts, 20 watts. But do the addition.

If you add them up. I feel that I secretly have 30-50 more watts above 40kph than someone who doesn’t have these advantages. That is a lot of power (or savings) when you are at maximum throttle. If we are hurtling down Middlebrook at 45kph and I’m putting a steady 400 watts into the pedals for 2 mins…the marginal gains means others are hurtling a lot more than me…or I have 50 more watts in the bank when I need them. And when we wind it up…600-800-900 watts in the final 100m sprint at 57kph. The cumulative 10% marginal gain is a game changer for a mid pack old guy.


I can hear Gaelen now saying…shut up and pedal harder! I look at people like Martin W. who puts in the work and he is a different human than he used to be. So, there is that route too to getting faster!

But, I can use every watt I can get.

Hence bring on the aero water bottles and dimpled socks.

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I am now using dual 63mm depth wheels, it will not stable with cross wind, especially when trucks go pass you.

For Handlebar, it really depends on the fitting figure, 38cm is not very common for the width of an adult’s shoulder.

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@ChrisP Don’t be coy.

Put up that side photo of you on your TT whip.

It is a study in “slippery-ness”

A.

Here’s a few great links:

Aerocoach (I raced against Xav at worlds in Poland) :slight_smile:

Skin Suit test:

Hand position test:

Here’s a position I use for longer TT’s. I used this for provincials this year and completed a 47km long TT averaging just under 46kmh at 307 watts average: (I use a full disc now)
I’ve also included a pic below of Lorie who is super aero.
Longer TT’s


Shorter TTs

Lorie’s Position

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I’m just over 180cm and measure 40cm across at the correct measuring point. Bikes today are generally spec’d with bars that are too wide for the rider. You can easily go 2cm below that correctly measured width with zero issues and be faster in the process. World Cup track riders (sprinters) are riding bars as low as 32cm and are WAY broader/more built than the average rider.

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Great thread @ChrisP . Some good advice even for those of us that don’t TT. :grimacing:

If you’re looking for some science and history of aerodynamics and bicycles, I recommend this paper. It’s amazing to see how we have progressed in making bikes slip through the air better. The paper also touches on some key findings for tube, wheel, spoke, and handlebar tests.

It’s a bit of a long read (the link below allows you to save a pdf (button at the top)) but I think worth it if you’re interested in this topic.

Cheers

Some really cool stuff here, especially the history. Anyone have anything slightly more modern? I know things are always changing but would be interesting to see something independent from the manufacturers. Hambini is an interesting source but more is always better!

Thanks appreciate it. Yup the tips are beneficial for road, gravel TT’ing. :slight_smile:

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Here’s another great video:

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One more tip:
Movement is less aero than staying in one position.

A less aero body position that you are comfortable holding is faster than the more aero position that you move out of because it’s uncomfortable.

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That’s a great tip…even in a great aero position just moving your head a few centimetres can interrupt airflow for 30s or longer.

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In the Tour Down Under they banned TT bike this year due to logistics of getting the bikes to Australia.

For those who like to do road bike TTs (myself included this year after selling my TT bike) this is a great article on optimizing your road bike.

Alberto Bettiol won the prologue (5.5km course) averaging 52.2kmh and finishing in a time of 6:19!

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A great video by Ollie at GCN who’s a TT aficionado :slight_smile:

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