eljayski 

To this point, I had noticed an occasional "tick" or creak with the pedal that eventually fell off. I shrugged it off as just an idiosyncrasy but in retrospect, that should have been a warning to me.

bikingshearer 

A pedal should never - repeat, never - come off for that reason, especially since it is easy to install it correctly, easy to the point that even a boneheaded ham-fisted amateur first-timer can figure it out. Rocket science it ain't.

If the mechanic did indeed fail to tighten the pedal down correctly, the only possible reason I can think of is if he threaded it in part way, was interrupted by a phone call or something, and forgot to finish installing the pedal when he came back. In that case, I would expect noticeable damage to the pedal threads, the crank threads or both such that one or both are no longer useable.

PeteHski

This pedal must have been very loose to start with. Not even nipped up against the crank arm face.

Along with other shoddy work reported it’s time for a new shop/mechanic.

indyfabz

As noted above, I did it once. And it was hardly my first time installing pedals. (Among other things, I had previously boxed and reassembled bikes for unsupported tours.) Who knows? Maybe I got distracted by something, focused by attention elsewhere, and forgot to properly finish the task. Maybe you’re perfect, but I think it’s not above the rest of us to make obvious mistakes.

PeteHski

It sounds like the mechanic was making lots of mistakes. I had one shop mechanic make the following mistakes on my full suspension mtb in a single service:-


1. Re-fitted the rear shock upside down so that the air valve was pressed right up against the frame.
2. Cut the dropper post cable too short, making it impossible to latch the post in the high setting.
3. Left all the downtube cable guides loose.
4. Left the drive side crank loose.

The bike basically fell apart on the next ride! Never been back to that shop since.

rsbob 

Sounds like either a new employee or incompetent. I would have returned to the shop and had a word with the manager to discover which employee had done the work, have him retrain/monitor their work and have a discussion about potential liability. Some one else could have been injured if management is not notified. Besides, you may have gotten a free something out of it as an apology.

Polaris OBark

I had this happen on a low-cost bike I bought in Cambridge, UK. I rode it out of the bike shop after purchase and almost immediately one of the pedals came off, and it was like getting a nasty kick in the nuts. I took it back as soon as I could walk again, and made them fix it.

I still don't really grasp how it happened.

On my own normal bikes, I put the pedals on finger-tight, because I don't like having to hammer on them to get them off again. I have never had one come loose.

PeteHski

I was very busy at the time (which is the main reason I didn’t service the bike myself). I did make them fit another dropper post cable as I happened to notice the problem when I picked up the bike from the shop. But the other stupid errors only became apparent when I rode it a few days later. Fortunately no damage was done so I just decided to move on and never use this shop again. This was about 5 years ago. I usually do my own bike maintenance and this experience reminded me why I should.

Metieval

Hmm

I've ever had a pedal come loose let alone fall off. Then again I'd notice a loose pedal instantly.

On that note, I only snug my pedals. There is no need for them to be tight.

smd4

I tighten my pedals. There’s no good reason not to.

Lamont Cobb

I've never had a pedal fall off, that I can recall.

Homebrew01

Pedals should be tight, but I hope people don't go crazy and over tighten pedals. That's not good either.