You may be able to bend a banana a bit but go too far and you’ll be sorry. Same goes for bicycles. All frames flex but it you go to far it won’t spring back. It also means bad news when you roll it into the bike shop as bending is a classic sign of an overload like a crash or other mishap.
With the way bikes are now, light and thin bending is rare. Most of the time instead of bending you’ll get a compression failure and wind up with something that looks like a crushed tin can. Once in a while though the planets can lineup to make something special happen.
A few years ago a shop near to us called in a report of a bent frame–one of our beefiest. Apparently, the rider was just riding along the sidewalk when it happened. They dropped it in a box and the next morning it was beside my desk. When I cracked the box open my first thought was this bike never came in that colour but that was quickly submerged by seeing the top and down tubes bent in perfect matching arcs. No dimples or any other indicators of a crash.
I started working over the frame with tools and magnifying glass but as I did I started to have a surreal sensation I could squeeze and manipulate the tubes like they were putty. I hung the head tube on a solid bar of steel fixed to the floor and leaned on the frame. Right before my eyes it straightened out. After checking out my powers on other objects in the shop
I concluded I had not suddenly been gifted with super human strength.
A call to the bike shop for information on who had painted the bike revealed that the rider had given it to a powder coater who did absolute bang up work on lawn furniture and car parts. He’d offered a special deal to slip the bike in with a batch of other materials for a one of a kind paint job. He wound up baking it for so long at far too high a temperature that the
material had utterly lost any semblance of strength. While the thermometer on his oven may have looked OK to him, the actual temperature the frame was raised couldn’t be determined since it was in with a batch of auto parts that were all much bigger, and heavier. The steel parts may have been at the right temp for the proper time, but the much smaller alloy bike frame was no doubt nearly glowing by the time the paint had baked on.
Unfortunately for the rider the painter washed his hands of responsibility since in his opinion the paint was still sticking and not flaking off. Any collateral damage was the rider’s problem for not knowing better. At the end of the day the rider got a new bike thanks to the shop and his Kona rep and I don’t think he ever an again felt the urge to try and separate himself from the pack with a flashy new coat.