Condensed answer: Carbon fiber has poor resistance to clamping/crushing force. For that reason, most carbon handlebars are not compatible with aero bars that clamp onto them. However, there are some exceptions.
The Problems With Aero Bars On Carbon Handlebars
- Poor Resistance to Compression
Carbon can be crushed rather easily if a component is overtightened. Hence why it’s so important to use a torque wrench and respect the manufacturer’s specifications when mounting parts on carbon components.
A carbon bar is reinforced/thicker around the stem area because the zone has to withstand a lot of stress, but this isn’t always the case for the sections where the aero bars are mounted.
Therefore, unless the manufacturer has explicitly specified that the bar is compatible with aero bars, it’s better to assume that it’s not.
One of carbon’s best features is that it allows the manufacturing of components in a futuristic shape.
Some carbon handlebars have a flat top section designed to cut drag and provide more comfort for the rider’s hands.
This type of carbon handlebars is incompatible with basic aero bars not only due to carbon’s weakness but because of the non-circular shape too.
List of Carbon Bars Compatible With Clip-On Aerobars
Below you will find a list of carbon handlebars that are compatible with clip-on aero bars according to the manufacturers’ websites:
- Bontrager XXX Aero (231g)
- Bontrager Pro IsoCore VR-CF Road Handlebar Legacy (249g)
- SES Aero Road Handlebar (compatible only with the SES Aero Extensions)
- Syntace RareLite Carbon L (214g) (compatible with Syntace C3 aero bars)
The next list contains carbon aero cockpits with integrated aero bars:
Handlebars With Integrated Aero Bars
- Zipp’s Vuka Aero (846g)
- Profile Design Aeria T2 Carbon (663g)
- Vision Metron TFA (1155g)
- Alloy handlebars
If aero bars are important to you, and you want to have the greatest variety of options, the only solution is to simply switch to alloy handlebars.
Aluminum has a much greater resistance to impact and clamping force. Also, aluminum bars are a lot less likely to break unexpectedly. Hence why even professional cyclists continue to use alloy bars.
Truth be told, a quality alloy bar is extremely light to the point where carbon handlebars offer non-measurable value, especially to recreational cyclists.
FAQ: What’s the weight difference between carbon and aluminum bars?
The table below compares the weight of carbon and aluminum bars:
|DEDA Piega 26||260g||LEVELNINE Pro Team Carbon Stealth||215g|
|Ritchey Comp ErgoMax||320g||Easton EC70 Aero Carbon||255g|
|DEDA Speciale 26||320g||Ritchey WCS Carbon Streem II||235g|
|Ritchey Comp Butano||295g||LEVELNINE Pro Team Carbon||215g|
|PRO PLT Compact Ergo||275g||NEWMEN Wing Bar Advanced 318||200g|
|Zipp Service Course 70 XPLR||305g||PRO PLT Ergo Carbon||195g|
|Ritchey WCS Streem III||275g||3T Aeroflux LTD||223g|
|Procraft Road Pro Compact Classic||280g||Easton EC90 Aero Carbon||230g|
|Syntace Racelite 7075||256g||PRO Vibe Di2||219g|
|Cinelli Giro d’Italia||280g||3T Aeroflux LTD||223g|
On average, the carbon bars in the table are 65.6grams lighter than the alloy ones. The difference isn’t substantial unless one is trying to build the lightest possible bicycle.
Note: The carbon bars in the table are not necessarily compatible with aero bars. Check the manufacturers’ specifications to know whether you can install aero bars on them.
- Aero Bars Attaching to the Stem
There are aero bars models that can be mounted directly to the stem. In that case, the rider is bypassing the handlebars, and there’s no clamping stress on them.
- Integrated Carbon Bars
Another option is to buy a carbon cockpit with integrated aero bars. Those types of setups are highly adjustable and look very slick but have notable downsides, namely:
- High price
- Weird shape (sometimes)
- Not compatible with all frames
- Ignore Aero Bars
The final option is to simply skip the aero bars altogether. Truth be told, most people do not really need them for recreational riding. Aero bars shine the most in triathlon and time trial competitions.
They’re absent from Tour De France Bikes because they may cause severe injuries during a collision. In that regard, aero bars are similar to bar-ends.
FAQ: What is the danger of combining aero bars with non-compatible carbon handlebars?
Carbon is a delicate material that needs extra care. If its needs are not respected, a crack may occur and cause sudden and unexpected failure.
If the bars brеak, an accident is pretty much guaranteed even if the rider is moving at a slow speed. The outcome ranges from small bruises to a lethal end.
In this case, there’s no place for irresponsible behavior. If you are unsure whether a carbon bar is compatible with aero bars, do not put such components on it. The risk isn’t worth it. It’s better to get a set of aluminum bars and add 50-100 grams to the bike than to crash.