Jim’s Tech Talk
By Jim Langley
Maybe you’ve heard the saying “even smart people make dumb mistakes.” Not that I’m feeling particularly smart about now, but I’ve been repeating that old saw lately trying to stop thinking about a recent very dumb mistake. Maybe sharing it will save one of you from making it.
El Morro National Monument
To recap, last week my wife and I were RVing in New Mexico and we stayed in a lovely and totally free (!) campground at El Morro National Monument in Ramah, New Mexico. One amazing feature here are the over 2,000 petroglyphs, signatures, dates and messages, left by the Zuni people, Spanish conquistadors and American soldiers and travelers on the base of Morro Rock’s wall.
What drew them to Morro Rock was the 200,000 gallon pool of water at its base, the only source of fresh agua for miles. This natural reservoir (created and fed by rain runoff and snow melt) also supported ancestral Puebloans who built housing for 500 to 600 people atop the rock in the year 1274. They called their clifftop village Atsinna (translation: where pictures are on the rock). The photo shows some of the ruins atop Morro Rock, the other amazing feature here.
Riding On One of the Oldest Routes in America
I was excited to ride from the campground because Highway 53, the only road there, traces the path that all these folks traveled to get to El Morro. It’s part of the Trail of the Ancients Scenic Byway. It was a beautiful drive in the RV getting to the park and even nicer to be spinning down the road on my Cervelo.
When I returned to the campsite, I carefully leaned my featherweight carbon wonder against a tree next to our RV. I made sure to lean it in such a way that it couldn’t fall toward the tree or back into our rolling home on its own.
Notice that I said “on its own.” That was my stupid mistake. Driving across Arizona and New Mexico to get to El Morro we had experienced ferocious winds. Even though we drive a 24-foot Lazy Daze Class C RV (smallish as RVs go), at times I had to arm wrestle with the steering wheel to keep our rig in our lane. And, while hiking we had to tie on our hats and watch our footing. One of the rangers in New Mexico told us the gusts were at times up to 55 mph.
Yet, that day on the bike had been calm so I completely forgot about the gusts when I parked my bike against the tree. I went into the RV to clean up and when I came out, our RVing buddy Sue who planned our trip told me that the wind had blown my bike over.
You can see in this photo that my poor bicycle never had a chance. Best I could figure looking at it lying there and then back at the tree and thinking how I had parked it, I believe the wind pushed a branch and that branch hit my bike knocking it over.
Unfortunately the bike’s top tube took the full force of the blow, which was delivered by the sharp point of a rock. In the next photo here you can see how the rock cracked the frame almost as neatly as splitting firewood with a hatchet. The crack in the frame travels more than halfway around.
Frame Materials Comparison
Before completely blaming the carbon frame material, it’s only fair to point out that an aluminum and steel frame suffering the same blow would dent. The difference obviously is that the carbon cracked, which is worse damage than a dent. I haven’t taken any steps to investigate how far through my tubing the crack runs but a cracked carbon frame is risky to ride on.
In contrast, dented steel and aluminum frames typically keep right on riding as they did before they were damaged. I have never tested the dent resistance of my titanium bicycle. I’d be interested if any of you have dented yours.
The thing about monocoque carbon frames like my Cervelo S5 is that they’re created with a heat-cured resin, which results in a crystalline structure. Sort of like how an EMT might save you in a crash by shattering your window simply by hitting it with a pointed instrument – that’s what the rock did to my frame.
Laying Down is Safer than Leaning
The moral of this sad story is that I should have known better than to park my bike by leaning it. Especially since I knew the wind was fierce and also unpredictable.
I should have parked it by gently laying it on its left (non-drivetrain) side on the ground. In that position – as long as it was where no one could step on it or heaven forbid drive over it, it wouldn’t have been able to fall down and wouldn’t now be broken.
Repairing the Frame
I haven’t had time to look into it yet, but my plan is to have the frame repaired by one of the carbon companies that specialize in it. I will let you know how it goes if I do that. Please comment if you’d like to share your carbon bike repair.
Jim Langley is RBR’s Technical Editor. He has been a pro mechanic and cycling writer for more than 40 years. He’s the author of Your Home Bicycle Workshop in the RBR eBookstore. Check out his “cycling aficionado” website at http://www.jimlangley.net, his Q&A blog and updates at Twitter. Jim’s cycling streak ended in February 2022 with a total of 10,269 consecutive daily rides (28 years, 1 month and 11 days of never missing a ride). Click to read Jim’s full bio.