Have a full carbon fiber Zona tandem with only 30,000+ miles on the odometer. A tandem takes a lot more stress/torque with 2 folks pedaling than a single.
Also have a c/f Zona single with only 10,000 miles on the odo.
Steel never breaks huh?! Our steel tandem broke twice: once at 50,000 and again at 56,000 miles. Sold it with 64,000 miles on the odo.
Any material can eventually fatigue and fail.
Yes we keep our bikes a long time . . . as well as our cars.
Our Accord station wagon is only 13 years old with 145,000 miles on the odo. Quality and proper care/maintenace is the answer!
Pedal on TWOgether!
Rudy and Kay/zonatandem