I had a Raleigh mtb with the bonded frame. Bought it new. It used the glue that they use to put airplanes together. Supposed to be guaranteed forever. I’m never flying again. It was otherwise such a piece of shite, geometry wise, that I gave it to my neighbors 70 year old father for the bike path. He passed on a number of years ago. I’ll have to tell his son to junk it.
Danny Mckasker snapped his aluminum bars right off in one of his videos, dropping off of a telephone box. As I said earlier, industry standards are to replace aluminum bars every two years. I’ve cracked aluminum mountain bike frames before and I broke a steel frame tube right through. I too went fast down a set of long concrete stairs in an old mining ghost town, did a front wheelie trying to stop at the bottom and crashed sideways into the woods. I torqued the seat going sideways and the seat tube broke at the bottom of the seat post, about 30 cm down from the clamp. It either got stuck between two trees or I fell on it. I think I fell on it, it was quite a smack, loud. The seat was bent and pointing in several directions. I got back on and started to ride it and I thought it was an a swing bike, whoope, such fun. Everyone thought I was dead. It dissuaded several other riders from going down the steps. I did that many times before, but never so fast. I couldn’t stop, as the stairs now has woods growing pretty close to the end. What to do, pound the seat post past the frame separation, and ride it out. The rock gardens made it a little wiggly, but it was rideable. The frame is now hanging, in the woods, in a tree, by a trail that ate it. Steel forgives and can’t sometimes be jury rigged enough to ride. More bad advice, if you’re riding in a group where riders have different diameter rims, and someone has a 650b inner tube, fit it into a 26, 27.5 or 29 wheel. If you get a flat and have no inner tube, disrobe and put all your apparel inside the tire. Hide in the woods until dark and then ride out. If your a roadie, then a shirt will work. I never take my own advice.
What happens when your mast fails? How about the hull?
If the mast fails it falls down. I have been on a boat racing in 1987 when it happened at 3am, mid channel. The whole rig went over the side, of course it was windy and we had to act fast before a stay cut somebody in half or the mast punched through the hull. Not fun, out with the bolt croppers and cut the whole lot away FAST. £50,000 bill for the insurance. What failed? A £10 pin in a rigging link sheared. FWIW it was an aluminium mast and stainless rigging.
The problem with inspection is the lack of it, and the lack of expertise to carry it out properly. THEN there is the problem of expense to get it done properly, which is resultantly not going to happen for most people. That shiny painted thirty year old featherweight road bike is going to be hurtling down a thirty percent gradient at some point with compromised components or structure. I would not think twice about lightweight carbon parts, as long as there is a level of redundancy for when it goes wrong.
.
Fatigue? I was going down steps on mine last night like I was 15 years oldMany used bikes have received impact stresses, especially if they are 30 years old.
It's surprising how reliable carbon fibre is, and also bonded frames.
Impact is much worse than age for them too!
I'd love to say they were less reliable than steel (because I don't like them as frame materials and methods) but most broken frames we see are caused by impact or corrosion. (and often both)
...or fatigue in the case of cannondales
(To be fair most aluminium fatigue failures are caused by poor seatpost fit or insertion)
