Aero Bars
Handlebar extensions that position riders in a tucked, aerodynamic posture — standard on triathlon and time trial bikes.
Understanding Aero Bars
Aero bars (also called TT bars or clip-on extensions) are handlebar attachments that allow cyclists to rest their forearms on padded armrests while gripping bar-end extensions in front. This position tucks the rider's torso low and narrow, dramatically reducing frontal area and aerodynamic drag — the primary force slowing you down on flat terrain.
The aerodynamic savings are substantial. Wind tunnel testing shows that moving from standard road bike drops to an aero bar position can save 30–60 watts at the same speed — that's equivalent to months of fitness gains for free. For triathletes and time trialists, aero bars are the single most impactful equipment upgrade after the bike itself.
Aero bars come in two forms: clip-on extensions that bolt onto existing road bike handlebars, and integrated aero bars built into dedicated triathlon/TT bikes. Clip-ons are affordable ($50–$200) and work for most triathletes. Dedicated TT bikes are fully optimized around the aero position but cost significantly more.
Key Facts: Aero Bars
Key facts and insights about aero bars that every endurance athlete should know.
Reduce aerodynamic drag by 20–30% compar
Reduce aerodynamic drag by 20–30% compared to riding on the hoods
Save 30–60 watts at the same speed
Save 30–60 watts at the same speed — equivalent to significant fitness gains
Banned in most road cycling group rides
Banned in most road cycling group rides and mass-start races (safety risk)
Legal in triathlons and individual time
Legal in triathlons and individual time trials
Pro Tips: Aero Bars
Get a proper bike fit before using aero bars — a bad aero position causes back, neck, and shoulder pain
Practice riding in the aero position for progressively longer periods in training
Never use aero bars in group rides or near other cyclists — you can't brake quickly from the aero position
Start with clip-on extensions on your road bike before investing in a dedicated TT/tri bike
Frequently Asked Questions About Aero Bars
Most road bikes accept clip-on aero bars, but fit matters. Your saddle may need to move forward, your stem may need adjusting, and your reach to the extensions must be comfortable. A 30-minute bike fit session can ensure the position works. Very aggressive road bike geometries sometimes don't adapt well to aero bars.
On flat terrain, 1–2 mph faster at the same effort is typical. Over a 40K bike leg, that's 3–8 minutes of free speed. The benefit decreases on hilly courses where speed is lower and climbing dominates. But for any triathlon or time trial with significant flat sections, aero bars are the biggest speed-per-dollar upgrade available.
Related Cycling Terms Terms
View all in Cycling TermsFTP (Functional Threshold Power)
The highest power output you can sustain for one hour, measured in watts. Key cycling fitness metric.
Peloton
The main pack of riders in a road race. Riding in the peloton reduces wind resistance by up to 40%.
Gran Fondo
Italian for "big ride" — a mass-participation long-distance cycling event, typically 100+ miles.
Watts per Kilogram (W/kg)
Power-to-weight ratio — the most important metric for climbing performance in cycling.
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