I would suggest VERY unlikely unless all the respective components were 'parade ground' clean and the service monkey was in the habit of going over every component with a pretty powerful magnifying glass. And as the shear appears to have taken place within the part of the axle that was inside the crank arm, even less likely that it would have been noticed - !
Sheered Crank bolt
- Thread starter NotAnother Cyclist
- Start date
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Drago
Legendary Member
- Location
- Suburban Poshshire
Funny you mention cleaning. Apart from making a bike good and spangly, it you do it properly it forces you in inspect and touch every component, making regular cleaning an important part of the safety regime.
mjr
Comfy armchair to one person & a plank to the next
- Location
- mostly Norfolk, sometimes Somerset
I see... and you're careful to clean out cracks in the BB axle that you don't know exist which are mostly inside the crank end? Sorry but
Drago
Legendary Member
- Location
- Suburban Poshshire
You might be flabbergasted @mjr but its what the countries premier training body endorses. It takes maybe 30 seconds, which is not an unreasonable price to lay to avoid being a quest of the NHS.
I'd be a damn sight more flabbergasted if my crank fell off and I ended up in Hospital, like the poor unfortunate OP. I know which I prefer.
No disrespect to you mjr, you do what you want on the bike, but I'm MIAS L5 and get paid (occasionally, when I can be bothered) to train the Feds, Ambo and Search and Rescue personnel in basic maintenances, advanced on road skills, off road techniques, nutrition and hydration, defensive tactics, first aid to FAST level, search techniques, and a load of shizzle. Were not talking mickey mouse bike ability stuff. When you're one of the thirty of so L6 trainers in the country then you'll be qualified to pick fault with the syllabus.
I'd be a damn sight more flabbergasted if my crank fell off and I ended up in Hospital, like the poor unfortunate OP. I know which I prefer.
No disrespect to you mjr, you do what you want on the bike, but I'm MIAS L5 and get paid (occasionally, when I can be bothered) to train the Feds, Ambo and Search and Rescue personnel in basic maintenances, advanced on road skills, off road techniques, nutrition and hydration, defensive tactics, first aid to FAST level, search techniques, and a load of shizzle. Were not talking mickey mouse bike ability stuff. When you're one of the thirty of so L6 trainers in the country then you'll be qualified to pick fault with the syllabus.
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mjr
Comfy armchair to one person & a plank to the next
- Location
- mostly Norfolk, sometimes Somerset
I check the steering as I unpark the bike and brakes as I pull away (I actually do ABCD in reverse order), but I don't check the electrics, most of the transmission (removing the chain guard/case is not a quick check), oil, or pressures beyond a quick glance because they're mostly non-critical, failures are more obvious when moving and I don't carry oil with me everywhere. Checking the footbrake while not riding requires a stand and isn't definitive - it's better to do it when riding away and going slow enough to stop by putting feet down if needed.
A 30-second version of any check is almost certainly not going to spot a BB axle cracked between crank arm and frame. You'd need to wash all road dirt off the nooks of the BB area to stand any chance of seeing it and probably still wouldn't spot it then - are you really washing the bike every time before you ride off from some cycle parking?
In short, I feel you're being unreasonable blaming @NotAnother Cyclist for not checking the bike enough to spot that. It's up there near a steerer splitting in two inside the head tube for a hard-to-spot freak failure - you might spot it if you do a full service at the right moment, but not in ordinary use.
The syllabus is fine. I'm just saying it's completely incredible to claim that some people actually do enough check to spot a BB axle crack before every ride of a bike. I even suspect that many of the people you train would say they do whatever check you say in order to pass the training, but really don't if the local Police bikes are anything to go by - the East of England Ambulance seem to keep their bikes in better nick, but they carry a lot more weight so I suspect they get serviced more and any faults are shown up more quickly by the stress of carrying all that kit.
Most people don't do such checks for motoring and that's far more dangerous, to others as well as oneself.
- Location
- The TerrorVortex
I don't think anyone would spot a BB axle that broke inside the crank. I've just had a look at my Brompton, andI'd never see that break without taking the cranks off. I sure-as-hell don't do that every ride, or even every year.
As I said, I've *never* seen a BB break like that. The OP was incredibly unfortunate IMHO, and I can only hope that Brompton will do the right thing.
I'm sure they will.
As I said, I've *never* seen a BB break like that. The OP was incredibly unfortunate IMHO, and I can only hope that Brompton will do the right thing.
I'm sure they will.
12boy
Guru
- Location
- Casper WY USA
In 40 some years I have never had a bottom bracket spindle break. I have, however, had a seat post break yesterday although that was entirely due to my own foolishness. Some years ago I scratched a 1/2 inch horizontal line across the post in the front to aid in getting the right height after dropping the post to lock the wheel in a fold. I figured being steel there would be no problem especially since it was about an inch above the frame junction. That was wrong. While riding home yesterday, I felt the seat slipping away beneath me and stopped to see if the bolt holding the pentaclip was loose when I saw the post hanging backwards, neatly torn along that line. The steel in the seat post was a lot thinner than I had supposed it would be and since there is a lot of stress it just tore it neatly across. Perhaps if the scratch were on the back or side it wouldn't have failed at all, but no more scratching seat posts for me.
rogerzilla
Legendary Member
I'm glad my Bromptons have Shimano BBs!
Another relatively common and unforgivable Brompton failure is the RH crank arm shearing from the chainring (they're just swaged together on most Bromptons, although I understand new ones have proper crank spiders). Most likely with more powerful riders who like to make a quick getaway from traffic lights.
Another relatively common and unforgivable Brompton failure is the RH crank arm shearing from the chainring (they're just swaged together on most Bromptons, although I understand new ones have proper crank spiders). Most likely with more powerful riders who like to make a quick getaway from traffic lights.
NotAnother Cyclist
Active Member
bonzobanana
Guru
Hopefully any costs Brompton mount up because of this can be reclaimed from FAG. When I've replaced bottom brackets in the past I've never even seen FAG as an option. Without knowing any details or reading this thread I suspect this is a lightweight aluminium component or at least hollow steel bottom bracket. Many years ago at 26 stone I rode every workday up a steep 1km hill using a budget steel mountain bike that was £60 new and that bottom bracket is still fine today but of course its a solid steel bar and made no attempt to be lightweight. Obviously the 26 stone bit didn't last long though as I was rapidly losing weight at about a stone or more a month. To me that is an unacceptable failure on the part of FAG.
Kell
Veteran
- Location
- High Wycombe/London
I changed mine anyway as it felt gritty and not particularly smooth.
Standard Shimano UN version in there now and it's been perfect for 18 months.
Standard Shimano UN version in there now and it's been perfect for 18 months.
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NotAnother Cyclist
Active Member
They inspected it, gave it a service and fixed it. I don't know if my accident was the reason for the recall, but several BBs have failed - whether my accident made them err on the side of caution and do a recall - possibly.
https://www.ft.com/content/aec54da2-a468-11e7-9e4f-7f5e6a7c98a2
I assume your bike will have been one of the ones recalled?
