1. Does the part give clear "warning" that failure is imminent (e.g. sound, feel, appearance), or will it just fail suddenly? (This characteristic is often a key design feature of safety-critical equipment)
2. When the part fails (note, different failure modes should be considered separately), what is the range of outcomes? (E.g. drive failure is dangerous if you're crossing the street, not so dangerous at other times; bell failure could occur at the worst possible time, etc). Then on the other hand we have structural failure of the frame and handlebars etc which are almost guaranteed injury.
So if you are riding a bike with lightweight racing components that aren't designed with a "leak-before-break" philosophy, riding in mountainous terrain in a crowded peloton, then yes - pretty much any small deviation from normal could cause a massive pileup. On the other hand, a leisurely commmuter ride on a quiet path has much more tolerance for component failure.
Regarding #1, on mountain bikes, carbon handlebars don’t give any warning before breaking. I quit using them after seeing one that broke on a friend’s bike. That could have been catastrophic.
I think the chain slipping off the cogs is one of the most concerning failure modes because it tends to happen only under heavy acceleration, e.g. to dodge traffic at a busy intersection. Everything can seem fine and then you're stranded without power exactly where you need it most. It's worth regularly checking for wear and correct adjustment.
Modern bikes allow novel attacks too. I wrote a blog post about how to downgrade the firmware of a Shimano Di2 groupset and doing a replay attack to shift someone elses bike.
There is also a certain matter of training --- badly bent a frame when I was young because I wasn't taught how to deal with a brake failure (rainy day and steel rims) --- the answer of course is to put one's foot up on the front wheel:
Of course, the biggest danger could also be addressed by training --- as a part of getting a driver's license, drivers should be taught the "Dutch reach":
One of the surprising failure i didn't anticipate with bicycles was how little contact the tires made with the road..
Even when the brakes fully work, the tires don't provide enough traction to stop quickly ...
Ever since that last big crash I am way more cautious about all the ways my bicycle can fail me while riding.. the one good thing is there aren't that many parts to worry about with bicycles
Being lights, bicycle have very efficient braking on the other hand. The thing is most people never train to brake in an emergency so don't know how to modulate them correctly nor how to stay upright even if you lock them up.
This undervalues how much it depends on context, how and where you ride. Cycling is varied.
My casual rides to the shop on my beach cruiser in my sleepy little town? Both my wheels could come off and I'd probably be fine. I'm rarely hitting 10mph.
Downhill mountain biking? Yeah, basically everything is important.
Aside, I was expecting an article comparing good software to a bicycle. Every part of good software being important and well maintained.
One thing to know about torque wrenches: it’s actually more important that they are consistent rather than having absolute accuracy. (for the most part) why is this? If you have four bolts tightening down a handlebar into a stem, using a torque wrench correctly ensures consistent clamping load and avoids creating a stress point.
Whether those four bolts are at 8.86nm or 7nm is not usually a big deal. This is strictly speaking about bicycles, however, not aircraft or rockets :) there are a few bolts where an absolute clamp load on a single fastener is important: controls on a carbon bar. For my experience, though I have seen some bike shop mechanics reef on these (8-12nm) without consequence, even though the manual clearly states 4nm. I would do exactly what the manufacturer says here.
Can confirm: my chain snapped cycling along Princes Street, and I couldn't wear trousers for about ten years. Turns out that sliding down the road isn't very good for the skin on your knee.
Most frustratingly: I'd already ordered a replacement, it just hadn't arrived yet.
I definitely had some failures that didn't really influence safety but were serious enough. I lost one of the pedals during a hike and still came back home on this bike. I guess it depends on what you do.
I see each part playing a functionality role, instead of safety-related role. A broken functionality might cause a safety issue. but it is still a functionality issue. A rider could fall off when a pedal is broken. That's just an undesirable consequence of broken functionality. A broken functionality always means things not working as expected, and naturally causing unexpected results. Most unexpected results can be safety issues, unless it is a win of a lottery.
Speaking of which. Last week I parked my bicycle against a car. The owner got angry at me, which I don't understand, people park their bicycle against my bicycle all the time. And by doing that, it is far more likely that safety critical parts are damaged.
I was trying to reinstall my rear wheel the other day after removing a bike trailer. I apparently didn't tighten it down enough and the wheel came out of the brackets as soon as I started to ride, causing an instant crash and a lot of bruises.
Things like that make me feel apprehensive about trying to learn more bike maintenance stuff myself. It's almost inevitable to have to patch flat tires though so you're always going to be reinstalling the wheel yourself, but I don't touch the brakes even if it seems like an easy fix.
Pretty much all wheeled vehicle safety commentary on the internet is written by people who live in the filter bubble from that universe. Most everyone else rolls their eyes and continues on with their day.
This piece seems ignorant of regular people's realities. Many people cannot afford the luxuries of this elusive fancy "safe" bike with well-engineered parts, kept on a professional maintenance schedule. I suspect this really isn't an issue for most HN readers, and the fear-mongering just heats simmering angst. Remember a cure for angst is to 1) ride your bike and 2) donate time and resources your local bike repair cooperative or homeless shelter.
Author seems to forget the most important part of the machinery is the rider. What a glorious machine! He also seems to forget that millions of people in the world are riding bikes, motorbikes, and cars scrapped together from whatever they can afford or find. Forced to accept the risk, they usually get where they're going. I wonder does the author check out the maintenance of every Uber he hops into? "Let me see your torque wrench!?"
I've built and maintained all my own bikes since around 2005 with no training. It doesn't take a genius or a torque wrench to keep a bike rolling. I recently dropped my standards quite a bit on two bikes: One where I took a decent 2021 FS trail MTB I'd maybe ridden ten times on a black diamond downhill singletrack and another where I took a 1998 HT MTB with seized shifters, no grips, crusty, barely-functioning brakes and a sun-baked Hellraiser-looking rear tire held together only by a thin sheet of kevlar(?) around the streets of Portland, Oregon for three weeks wearing no helmet. I know, I'm a monster.
As an aside, I ride a 2005 Yamaha YZ250 (dirt motorcycle) my ex maintains... that feels sorta... dangerous.
I think the key is most people are ignorant. If people knew how to maintain such a simple thing as a bicycle, they would maintain them correctly.
Cost is mostly a non issue for most people. It doesn't cost a lot to maintain a non high end bicycle if you do it yourself. If you look at the shimano groupsets on the lowest end of the spectrum like shimano tourney, you quickly realize they need much less bicycle specific tooling as the high end ones. For example instead of socket bolts they are using hex head bolts that can be torqued with simple wrenchs or a single adjustable one. The 2 only specific tools are the threaded cassette tool and the square taper bottom bracket extractor. Everything else can be done with a very basic set of tool and there is nothing super challenging.
1) avoid nockoffs of seat posts, stems and handlebars. Well known
2) A worn front chain ring won't negatively impact a rider.
3) it is a bicycle, not a helicopter.
4) Fear mongering is unnecessary
5) A torque wrench needs to be consistent. so long as it is within 10% you are fine
6) sounds like a bike shop owner trying to drum up business.
Topical, with RAGBRAI just around the corner. I'm constantly awed at just revolutionary the bicycle seems to be from an industrialization perspective. To me, bicycles and smartphones are two real thick lines to draw on when the world became something different.
25 comments
[ 3.1 ms ] story [ 48.1 ms ] thread1. Does the part give clear "warning" that failure is imminent (e.g. sound, feel, appearance), or will it just fail suddenly? (This characteristic is often a key design feature of safety-critical equipment)
2. When the part fails (note, different failure modes should be considered separately), what is the range of outcomes? (E.g. drive failure is dangerous if you're crossing the street, not so dangerous at other times; bell failure could occur at the worst possible time, etc). Then on the other hand we have structural failure of the frame and handlebars etc which are almost guaranteed injury.
So if you are riding a bike with lightweight racing components that aren't designed with a "leak-before-break" philosophy, riding in mountainous terrain in a crowded peloton, then yes - pretty much any small deviation from normal could cause a massive pileup. On the other hand, a leisurely commmuter ride on a quiet path has much more tolerance for component failure.
https://grell.dev/blog/di2_downgrade https://grell.dev/blog/di2_attack
https://bikenewportri.org/abc-safetycheck/
There is also a certain matter of training --- badly bent a frame when I was young because I wasn't taught how to deal with a brake failure (rainy day and steel rims) --- the answer of course is to put one's foot up on the front wheel:
https://bicycles.stackexchange.com/a/7287/7344
Of course, the biggest danger could also be addressed by training --- as a part of getting a driver's license, drivers should be taught the "Dutch reach":
https://www.theaa.com/driving-advice/safety/dutch-reach?msoc...
and riding a bicycle a mile or two in practice and a use of/review of hand signals should be a part of the road test.
Even when the brakes fully work, the tires don't provide enough traction to stop quickly ...
Ever since that last big crash I am way more cautious about all the ways my bicycle can fail me while riding.. the one good thing is there aren't that many parts to worry about with bicycles
My casual rides to the shop on my beach cruiser in my sleepy little town? Both my wheels could come off and I'd probably be fine. I'm rarely hitting 10mph.
Downhill mountain biking? Yeah, basically everything is important.
Aside, I was expecting an article comparing good software to a bicycle. Every part of good software being important and well maintained.
Whether those four bolts are at 8.86nm or 7nm is not usually a big deal. This is strictly speaking about bicycles, however, not aircraft or rockets :) there are a few bolts where an absolute clamp load on a single fastener is important: controls on a carbon bar. For my experience, though I have seen some bike shop mechanics reef on these (8-12nm) without consequence, even though the manual clearly states 4nm. I would do exactly what the manufacturer says here.
Most frustratingly: I'd already ordered a replacement, it just hadn't arrived yet.
Things like that make me feel apprehensive about trying to learn more bike maintenance stuff myself. It's almost inevitable to have to patch flat tires though so you're always going to be reinstalling the wheel yourself, but I don't touch the brakes even if it seems like an easy fix.
Author seems to forget the most important part of the machinery is the rider. What a glorious machine! He also seems to forget that millions of people in the world are riding bikes, motorbikes, and cars scrapped together from whatever they can afford or find. Forced to accept the risk, they usually get where they're going. I wonder does the author check out the maintenance of every Uber he hops into? "Let me see your torque wrench!?"
I've built and maintained all my own bikes since around 2005 with no training. It doesn't take a genius or a torque wrench to keep a bike rolling. I recently dropped my standards quite a bit on two bikes: One where I took a decent 2021 FS trail MTB I'd maybe ridden ten times on a black diamond downhill singletrack and another where I took a 1998 HT MTB with seized shifters, no grips, crusty, barely-functioning brakes and a sun-baked Hellraiser-looking rear tire held together only by a thin sheet of kevlar(?) around the streets of Portland, Oregon for three weeks wearing no helmet. I know, I'm a monster.
As an aside, I ride a 2005 Yamaha YZ250 (dirt motorcycle) my ex maintains... that feels sorta... dangerous.
Cost is mostly a non issue for most people. It doesn't cost a lot to maintain a non high end bicycle if you do it yourself. If you look at the shimano groupsets on the lowest end of the spectrum like shimano tourney, you quickly realize they need much less bicycle specific tooling as the high end ones. For example instead of socket bolts they are using hex head bolts that can be torqued with simple wrenchs or a single adjustable one. The 2 only specific tools are the threaded cassette tool and the square taper bottom bracket extractor. Everything else can be done with a very basic set of tool and there is nothing super challenging.