Sheered Crank bolt

[NotAnother Cyclist]

Yes. Where it happened does tend to have articulated lorries bombing round the corner - so my first reaction was to drag myself out the road. Luckily a few moments later a police car happened to be passing, so they sorted me out!
Broke both my leg bones, so may be a little while before I'm back on my bike.

 

[mjr]

[...] it's almost always when you are pulling away which is when the most amount of force is applied to the component that it fails.

More luck than anything else that it doesn't result in a serious accident. [...]

I don't really understand how a pedal vanishing is sufficient to unseat a casual rider rather than cause an epic wobble. Are you standing on the pedal to push off, as I think some cycle training courses teach? Are you pulling hard on the bars as you start off? Am I just really cautious starting because I've ridden some seriously untrustworthy bikes over the years?

 

[NotAnother Cyclist]

In my case, I wasn't actually stopped - the lights changed as I was stopping, so I was accelerating without having already stopped. The pedal didn't vanish from beneath my foot - it was the pedal on the other side which had vanished. I was pushing down on a pedal which suddenly lost all resistance.
I was sitting down, not standing. I wouldn't call myself a casual rider - I was trying to keep to the speed of the traffic as one would do in the outside lane of a junction!

 

[doginabag]

I don't really understand how a pedal vanishing is sufficient to unseat a casual rider rather than cause an epic wobble. Are you standing on the pedal to push off, as I think some cycle training courses teach? Are you pulling hard on the bars as you start off? Am I just really cautious starting because I've ridden some seriously untrustworthy bikes over the years?

Really? So if you go to put your full weight down one leg and the pedal falls away from under you, you can't see how, with a bike between your legs, you might not have proper balance when you hit the ground?
Even if you do style it out, you have no forward momentum, the driver behind if they are close can still potentially hit you whether you are up or down.

 

[mjr]

Really? So if you go to put your full weight down one leg and the pedal falls away from under you, you can't see how, with a bike between your legs, you might not have proper balance when you hit the ground?

I can't see why one has "put your full weight down one leg" instead of just pushing the pedal enough to make the bike move... but @NotAnother Cyclist has explained it as "trying to keep to the speed of the traffic". I can't do that and gave up trying some time ago. Sod 'em. I've as much right to be on the road as they do.

Even if you do style it out, you have no forward momentum, the driver behind if they are close can still potentially hit you whether you are up or down.

That's ever-present "fear from the rear" - even when I have forward momentum, motorists generally go faster but haven't hit me yet. Most are fairly good about not driving into things - hooking, crossing, side-swiping and dooring are all much more common collision types.

 

[Cycleops]

I would complain about this to Brompton. This really shouldn't have happened on a bike this young. If it was the States an injury lawyer would have already been engaged.

Hope you recover soon.

 

[Drago]

...and the injury lawyer would have gone back to his game of Golf when he discovered the bike hadn't been serviced recently by a qualified engineer.

 

[NotAnother Cyclist]

...and the injury lawyer would have gone back to his game of Golf when he discovered the bike hadn't been serviced recently by a qualified engineer.

But would a service have picked this up?

 

[NotAnother Cyclist]

I would complain about this to Brompton. This really shouldn't have happened on a bike this young.

I've emailed them.

 

[Kell]

First off - Ouch. Hope you get better soon.

Second. I've never heard of this, and therefore have to assume that it's fairly rare. I'm always wary of putting too much power down at junctions after my chain snapped and I landed on the cross-bar of my old Dahon. Broke my Cocyx which still hasn't healed properly and becomes uncomfortable on long car journeys in particular. As per you though, as the time I was more concerned with the cars that were bearing down on me.

I'm still confused as to how there was no resistance on your right foot though. Did the jolt of the BB snapping knock your chain off? (I don't suppose you'd know the answer to that in all honesty.)

 

[Drago]

But would a service have picked this up?

Perhaps, perhaps not, but you can bet the vendor will tell the court it will, and now the item has failed the buyer can't disprove any such claim.

Presumably to don't do pre ride checks yourself?

 

[Cycleops]

I've emailed them.

I really think you need to scare them a bit and stop them thinking that they can fob you off with a pat response as @Drago says.

If you can engage one of those no win no fee lawyers ( hateful I know) he'll write the correct sort of letter and that will let them know you're serious. That'll put a firework up their a**e. They may even make you an offer straight off which will mean you won't have to an engage engineer to write a report.

Good luck.

 

[mjr]

Presumably to don't do pre ride checks yourself?

Typical pre-ride checks won't detect a failed crank-BB attachment unless it's pretty much hanging off, would they? I don't think it's in the ABCD or M checks - checking the cranks is in the M check, but not with similar pressure to a hard start.

 

[Drago]

ABC isn't a full pre ride check, only suitabke as a quick top up check if you leave a bike unattended for a short ride. M is short for Mickey Mouse if you're serious about safety.

If the damage were in any way visible, which is quite likely, BESTCOP would have picked it up. I practice what I teach, and those lessons are written in the blood of less conscientious riders.

 

[mjr]

I'm flabbergasted that anyone thinks a motorcycle-style BESTCOP (Brakes, Electrics, Steering, Transmission, Chains/belts, Oil, Pressures) should be done before every ride. I also doubt that a cracked BB axle would be spotted even then - it's pretty hard to see much of that axle and I'm surprised if anyone looks closely enough at the non-drive-side BB axle while rotating it to spot what's probably the thin end of a crack. Edit: and BB axles are often black or dark brown and the crack could easily be full of black/brown crud.