Workshop: Carbon frame repair
TOUR also interviewed Dirk Zedler, an expert for bicycles and e-bikes, who spoke about the opportunities and risks of repairing bicycle parts made of carbon fibre.
TOUR: What damage to carbon frames can be repaired without hesitation?
Zedler: A top tube damaged by falling over or the handlebars falling in and a torn dropout are the most common types of damage. I have no safety concerns if an experienced specialist repairs it. Some time ago, we analysed repaired frames in the laboratory with regard to their durability: none of them broke at the repaired point. Actually, all repairs along the tube are manageable.
Professional repairs last!
TOUR: What are the limits of carbon frame repair?
Zedler: I would not recommend repairing fork steerer tubes, handlebars or seat posts. These are the parts that are most likely to have safety problems anyway. Otherwise, it's difficult if you want the repair to be completely invisible. With a lot of effort and a good painter, this is often possible. However, the paintwork may then be more expensive than the repair. The rule is: functionality before appearance.
TOUR: To what extent and for how long is the repair company liable for its work?
Zedler: He must be liable for a defect-free repair work. If he promises structural strength and safety as the result of his work in the sense of "it's as good as new", he must also guarantee this. The functionality of the repaired component must be guaranteed. But we have never had a case on the table where such things were at stake. Professional repairs last!
Our carbon frame repair examples
- Scott Foil Torn off derailleur hangerRepair costs approx. 360 euros net, including clear coat (CarboRep)
- Rose Xeon torn off derailleur hangerRepair costs approx. 330 euros net, including paintwork (Triple-M)
- Specialised Tarmac two broken chainstaysRepair costs including painting approx. 540 euros net (PolyTube Cycles)
- Giant Propel Extension of the seat dome/crack in the top tubeRepair costs 400/350 Euro net, unpainted (Phoenix Carbon GmbH)
Sports equipment instead of hazardous waste: our four sample repairs in detail
Rose Xeon - Reconstruction of the torn off derailleur hanger
Just one chain jam can mean the end: The aluminium derailleur hanger on the Rose Xeon had held, but the carbon frame gave way. The weight-neutral and invisible carbon frame repair from Triple-M made the frame fit again. Cost: approx. 330 euros net.
Specialised Tarmac - Bandage repairs broken chainstay
The destroyed Specialized Tarmac had two major breakages. The right-hand chainstay was broken at the bottom bracket shell, the left-hand one in the tube. Both were rebuilt from the outside at PolyTube Cycles and then elaborately repainted. The stiffness values after the carbon frame repair correspond to a new frame. Costs including painting: approx. 540 euros net.
Scott Foil - Rebuilding the cracked derailleur hanger
The rear derailleur on the Scott Foil got caught in the spokes, tearing the derailleur hanger and thru-axle out of place. The carbon frame repair from CarboRep.de - like the Giant (below), it was not painted over for better visibility - is weight-neutral and saves the elegant frame. Price including clear coat: approx. 360 euros net.
Giant - Repair seat dome extension and dented top tube
On the Giant Propel, only the unrepaired paint damage on the dented top tube bears witness to the crash. Phoenix Carbon repaired it from the inside. The seat dome, which had been cut too short, was lengthened using the original material. A new one would also have been possible. Costs: 400 euros (seat dome), 350 euros (crack) net.
