Looking for some opinions from those who know more about bikes than me. That’s probably most people on here.
Usually do well over 100 miles a week on my 2023 giant TCR advanced. Had a fall yesterday, luckily only cuts and bruises sustained. I was up on the pedals during a climb, suddenly the left crank came off and I was on the road … just couldn’t believe this was even possible. It didn’t just fall off, it looks wrenched off . Feeling lucky the outcome wasn’t worse. Does anyone know what could cause this, surely poor quality manufacture? Or should I be wondering if the bike shop has done something wrong on the maintenance? I’m about 5”10 and 80kg – I’d like to put it down to my sheer power but that would be fantasy ! Appreciate your input..
by Mean-Hamster8031
6 Comments
That didn’t fall off. That broke. When most people say fall off, they mean it mechanically came apart. Without a good up close inspection, it would be hard to say if it’s a manufacturing or impact failure. Bring it to your local giant shop and see what they think.
Have you had any old crashes, pedal strikes, anything that would stress the crank arm? Had this happen on my old Trek when I finally got back on after a nasty fall, mechanic said the aluminum probably got overstressed in the crash and developed micro fractures
Aluminum crank I assume? It can happen, but usually it’s caused by a either a manufacturing fault, a crack caused by an impact, or metal fatigue over time. If this happened right after a crash, I’m guessing the crash is what ended it.
I’ve never seen a crank fail in this place, but I’ve had one snap at the mid point on me (and I have the scars to prove it). Count yourself lucky it didn’t fail at a more inopportune moment, and calm down with the watt bazookas.
Cranks are not indestructible believe it or not they are a disposable component just like everything else on the bike. If you ride enough everything is breakable, it’s just a matter of time.
damn, i hate carbon cranks, literally one of the worst places
It was likely damaged and fractured prior to this, where it finally imploded