Types of Triathlon Aerobars: Clip-on or TT, What Changes and Which to Choose

When you search for triathlon aerobars you find dozens of names: clip-on, TT, aero, flat, extensions... Behind that catalogue there are only two questions that really matter: what bike you have and how much you want to customise your position. This guide sorts them out and takes you to the right piece.

What an aerobar is and what it does

Aerobars (also called extensions) are the piece that lets you rest your forearms and bring your hands together out in front to close up your frontal area. In that position the air meets less surface head-on and you need fewer watts to go at the same speed. They have three zones: the elbow support, the extension and the hand grip.

The two families: clip-on and TT cockpit

Clip-on: they fit on the handlebar you already have

They are for anyone with a road, gravel or mountain bike who wants an aero position without changing handlebar. It doesn't matter what you call your handlebar (flat, aero, road): the kit mounts on the one you have. CarboXtrem has two:

• Basic kit (€280): carbon with a 3D-printed adapter for flat or aero handlebars of any brand.
• Custom aero aerobars (€450): also clip-on, but built to your body measurements, for racing.

TT cockpit: for a triathlon or time trial bike

The TT aerobars (€890) do not fit on a road handlebar: they are the complete cockpit of a triathlon or time trial bike, hand-laminated in carbon and made to your biomechanical measurements.

Quick comparison

How to decide without wasting money

1. You have a road bike and want to try an aero position: start with the basic kit. Before buying, read whether a time trial bike or a road bike with aerobars is worth it.
2. You race and position matters to you: the custom aero aerobars. The reason is explained in why S/M/L sizes hold you back.
3. Your bike is already a triathlon or time trial bike: look at the TT aerobars.

If you already have aerobars and the problem is the arm support, you don't need to replace them: read how to change only the armrests. And if you are unsure about the extension shape, see straight, curved or single-bar extensions.

After you buy

Fitting and adjusting them well matters as much as choosing them: follow the guide to fitting and adjusting time trial aerobars and check how wide to set your elbows.

Not sure which one fits your bike? Message us on WhatsApp with the make and model of your handlebar and we will help you choose. You can also see the whole triathlon aerobars collection.

Frequently asked questions

What is the difference between clip-on aerobars and TT aerobars?

Clip-ons mount on the handlebar you already have (road, gravel or mountain bike). TT aerobars are the complete cockpit of a triathlon or time trial bike.

Can I fit aerobars on a road bike?

Yes. CarboXtrem's two clip-on models are designed for that: you gain an aero position without changing handlebar.

How much do CarboXtrem triathlon aerobars cost?

The basic kit costs €280, the custom aero aerobars €450 and the TT aerobars €890.