Here are photos of bike parts I’ve managed to break or encounter over the years. The amazing thing is most of these broken parts were due to normal everyday use and not subject to abuse or accidents. Included are photos from both the major component manufacturers–Campagnolo and Shimano–on my own or friends’ bicycles.
This page documents just some of the broken bike parts I've had (or encountered) over the years. Shown here is my friend Dave and his crankset that totally seized onto the bottom bracket, and the only way to remove it was to cut it off.
A real shocker: in Feb. 2003 on a training ride, the 2 largest cogs on my 9-speed Shimano Ultegra cassette had SHEARED OFF! I replaced it with an SRAM cassette after that...
During the 2003 Davis 400k Brevet, my home-made light bracket snapped in half. Fortunately, I was just a mile from a store where I bought a whole roll of packaging tape, and taped the light to my handlebars (and ride until 2:00 a.m.!)
In early 2003 my right Campy Chorus Ergopower lever was shifting a lot less precisely. Here's why: this tab (held by my pliers) from the "G-spring barrel" broke off. Fortunately, Ergopower levers are fully serviceable, unlike Shimano's.
One day my left crankarm was really creaking from the very start of a 60-mile ride. At Mile 50, I looked down and saw the reason: a prominent stress fracture in the (Campagnolo Racing T) crankarm itself! (With ~12,000 miles, I think.)
My Speedplay cleats--which I have never replaced since I got them in 1999 (also ~12,000 miles?) were not in great shape anymore either, though they still worked fine. (And lasted about 4X longer than the plastic cleats for my previous Sampson Stratics.
I was riding off-road (on my road bike, and a long piece of barbed wire got tangled in the rear wheel, seizing the wheel. When the wheel seized, the tension tab on the rear derailleur (Campagnolo Veloce, above right) broke off. (On the left is an identical, unbroken derailleur for comparison.)
Another rear derailleur issue! This is Sharon's bike after crashing on the descent of Patterson Pass. Actually, the derailleur (Shimano Ultegra) only got scraped up; it was the bike's (Griffin Triton B4C) derailleur hanger that bent.
More detail on the Griffen's replaceable rear derailleur hanger. The one on the left is a new one; the one on the right is the bent one.
At Mile 20 of the 2005 Delta Century, the 3/8" bolt serving as a pivot for my recumbent's handlebars broke. Unfortunately steering is pretty important while cycling. End of ride.
Another view of the broken bolt.
After just 1.5 years my rear brake pads were hosed, especially after riding through the wet roads of the Butterfield Double. Look at how worn through they were (left) compared to the new ones on the right!
More detail of what happened: all 6 of the tabs that held the 2 largest cogs to the cassette body broke.
At Mile 0.5 of an 82-mile ride, Sandi's rear tire went thump-thump. Upon further inspection we discovered this. To think she raced a half-Ironman triathlon on this tire!
At Mile 20 of the same ride, my rear derailleur auto-shifted to the highest gear and I could not shift it to a lower one. This was the reason: the shifter cable housing had split!
While biking to Ripon with a 30-lb pack to meet up with Tori and Chris for climbing, this brand new bungee cord exploded, dumping the pack onto the ground.
While my friend Joe was near the top of Mt. Diablo on a sub-freezing day, the hub flange of his Bontrager wheel cracked and broke off.
The seat tube on Steve's coworker's MTB snapped in half. From Steve: "He is a real strong rider, but he is only 145 pounds so I can't imagine that he overstressed the frame."
From Steve: "I am surprised that there is that much horizontal force in the frame. The wielding on the gusset must have had too much penetration and weakened the tube."
My bud Tim's right-side pedal on his vintage 1980s road bike at the axle while he was biking home from the Fort Collins Library.
My friend Olivia's Diamond Back road bike had a broken bottom bracket cable guide that prevented shifting the front derailleur. I replaced it with an exact replacement from the Fort Collins Bike Co-op on Winter Bike to Work Day.
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One comment:
S
by SBarner |
Campagnolo had a bunch of problems with their aluminum castings in the 1990s and 2000s. You often see rear derailleurs with a hairline crack at the B-pivot, and that type of crankarm failure is sadly not rare. It is hard though to separate bad casting/forging from excessive stress.
The hex on the crank bolt is munged, which indicates that someone was a bit careless in tightening it at some point. Overtorquing this bolt can put tremendous stress on this type of arm, due to the tapered square interface.
The late Jobst Brandt noted that even when properly tightened, a square taper crankarm can be placed under failure-inducing stress by mechanics or owners who retighten the arm periodically. An undamaged, properly tightened arm does not loosen up, but mechanics who have had customers come in with failed (usually left) crankarms will often tighten any crank further on any service. The problem is that as the crank is used it beds in and this will make the bolt seem undertorqued when all it is supposed to be doing is to keep enough tension on the joint that it does not loosen up.
Even tightening a crank bolt back to its original spec can gradually increase the stress until the arm cracks. The proper approach is to tighten the bolt to spec when the arm is installed and then leave it alone. If the arm has loosened to the point of rocking, it will need to be replaced. And above all, do not grease the tapered interface or the bolt threads. If the bolt has been removed multiple times, add a drop of blue Loctite to the clean threads to keep it from loosening. ↩ Reply
One comment:
Campagnolo had a bunch of problems with their aluminum castings in the 1990s and 2000s. You often see rear derailleurs with a hairline crack at the B-pivot, and that type of crankarm failure is sadly not rare. It is hard though to separate bad casting/forging from excessive stress.
The hex on the crank bolt is munged, which indicates that someone was a bit careless in tightening it at some point. Overtorquing this bolt can put tremendous stress on this type of arm, due to the tapered square interface.
The late Jobst Brandt noted that even when properly tightened, a square taper crankarm can be placed under failure-inducing stress by mechanics or owners who retighten the arm periodically. An undamaged, properly tightened arm does not loosen up, but mechanics who have had customers come in with failed (usually left) crankarms will often tighten any crank further on any service. The problem is that as the crank is used it beds in and this will make the bolt seem undertorqued when all it is supposed to be doing is to keep enough tension on the joint that it does not loosen up.
Even tightening a crank bolt back to its original spec can gradually increase the stress until the arm cracks. The proper approach is to tighten the bolt to spec when the arm is installed and then leave it alone. If the arm has loosened to the point of rocking, it will need to be replaced. And above all, do not grease the tapered interface or the bolt threads. If the bolt has been removed multiple times, add a drop of blue Loctite to the clean threads to keep it from loosening.