Carbon Fibre frames have very thin walls that present problems for traditional cycle carriers. The clamps can’t get around the chunky frames, and the thin walls are easily crushed, especially if the clamp contacts at only a few points.

Bike manufacturers consistently advise against frame clamps.  Cannondale recommends tyre clamp type racks instead, see below.

When transporting your bike with a car rack, only fix your bike at the seatpost or fork dropout and never clamp the bike on any frame tube.

BMC Carbon care

Please note that further advice from other manufacturer’s recommends against clamping on carbon seat posts.

WHEEL CLAMPS & UPRIGHT ARM CLAMP

In this design, wheels are clamped in a wheel tray and the bicycle is held upright by an arm clamping the downtube. Do not use on bikes with carbon fiber downtubes. When clamp is tightened the carbon downtube can be broken. When clamp is looser, chafing can cause structural wear. A loose clamp can allow movement and possible chafing damage.

TYPE OF RACK DESIGN RECOMMENDATION. CLAMPS ON TIRES / WHEELS ONLY

This type does not use clamps on any other part of the frame or fork. Suitable for both carbon and aluminum frames This is the best system design because there is no potential cracking or crushing damage to the frame or fork. Chafing wear is avoided.

Cannondale Instruction Manual Page 101

Any bike carrier (e.g. roof, rear end) that requires the frame or bicycle to be mounted or clamped is not suitable for this bicycle.

CUBE instruction manual page 55

Transporting Canyon road bikes on conventional bike carriers is not permitted. Most clamps are potential sources of damage to large diameter frame tubes. Carbon frames are particularly susceptible to be being damaged irrepairably.  Unvisible damage occurring on this occasion may lead to severs crashes.

CANYON Instruction manual page 106.