a cracked (carbon) frame: would you say goodbye, or would you let it ride?

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Photo: velojoy
A bicycle mechanic discovers a crack in the frame of the author's carbon-fiber bike frame on the eve of a 100-mile ride. Will it be a go or no-go?

Picture this. Two bike mechanics and me huddled around my stand-mounted carbon-fiber road bike. We’re taking turns running our fingers horizontally across the right side of the top tube not far from the seat post. And feeling. A crack. Consistent with impact.

The damage, though minor in appearance and difficult to discern because it’s located at the edge of a gray decal, is cause for concern because dinged carbon-fiber frames have been known to fail — read fall apart — catastrophically. Imagine this happening at 35 miles an hour on a descent.

The good news, the mechanics note, is that load-bearing and torque in this section of the frame are comparatively light. If, say, the fork were cracked, this would be a no-brainer of a no-go. But this case is shadowy at best.

Another mechanic drifts through the shop: “Pack the bike yourself, did you?” he intones, both judge and jury. Well, yes I did disassemble the bike in New York and pack it in a hard case for shipping by commercial airline to California. Maybe I did something wrong. Maybe the airline dropped something on the case. Maybe the crack has been there for months. Who cares? At this point, it’s about being able to participate in a cycling event for which I traveled across the country.

An aluminum bike is available for rent. But I’m tall, and the fit and geometry are likely to be way off.  In addition, the stiffness of aluminum versus carbon could cause problems during a hilly, 100-mile ride.

Next up: a consultation at a high-performance bike shop one town over.

“It’s a tough call,” says the head mechanic there, tapping the length of the tube lightly with his wrench.

I consult with a nearby acquaintance, a life-long rider and former bike racer. Turns out he knows the owner of the shop personally and offers to call and get “the unvarnished truth.”

But, there is no clear-cut answer. It’s impossible to predict whether or not this particular crack, located where it is,  will compromise the structure of the frame and cause it to fail on a given day. In the end, the best advice I could find was to wrap the crack as tightly as possible with multiple layers of electrical tape, and to watch and listen for telltale cracking or crunching sounds. Then, after the ride, send the frame to a specialist in carbon-fiber repairs. (Subject of a future post.)

If it were a lesser, local event, I would skip it. But I came here to enjoy riding Lake Tahoe on my faithful steed. So pass the electrical tape.

Note to readers: The decision to ride a compromised frame was mine alone. I do not endorse or recommend this.

Photo: velojoy

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