Puzzle

[Gummo]

Last evening, a car pulling out from parking hit me and my bike last night - no major injuries to me but the front wheel which I'd intended to replace in the near future, needs doing now. Anyway, I decided to give a bike a good wash in honour of the imminent new wheel.

I left it in my shed to dry and went out later to inspect its unusual clean state (I cycle in very filthy places) and I noticed a wee bolt lying by the rear wheel. I don't know if this bolt had always been lying about but, I have no idea if it came off the bike (maybe due to the collision) or it was waste from some other DIY shenanigans that goes on in my shed.

Any ideas from the attached photos?

 

[Sharky]

Any missing bolts on the gear hanger, or seat post clamp?
Or even on your shoe cleats?

 

[C R]

It looks the right size to be the derailleur bolt, did you check the derailleur was in place?

 

[EckyH]

Any ideas from the attached photos?

It's a chain ring bolt.

E.

 

[raleighnut]

^^^^^^^^^^ Wot e Sed.

 

[silva]

next question is where is its nut

 

[Shut Up Legs]

next question is where is its nut

Maybe it doesn't have one, i.e. it's nutless (that's as far as I'll go, lest I be accused of sexism).

 

[Gummo]

It's a chain ring bolt.

E.

Seems okay from this image - can it be from anywhere else on my triple chainset?

 

[Sharky]

Changed my vote, to a chain ring bolt.

Try tightening the four shown in the photo. If any just spin round, the other side of the bolt could be missing.

The small inner chain ring must be bolted on to a separate bolt system, as the diameter of the bolts, appear to be larger than the diameter of the inner ring.
Good luck

Must be one of the "granny" ring bolts?

 

[C R]

Yep, not derailleur, chainring bolt.

 

[Gummo]

Changed my vote, to a chain ring bolt.

Try tightening the four shown in the photo. If any just spin round, the other side of the bolt could be missing.

The small inner chain ring must be bolted on to a separate bolt system, as the diameter of the bolts, appear to be larger than the diameter of the inner ring.
Good luck

View attachment 798826

Must be one of the "granny" ring bolts?

Just checked: they're all rock-steady.

 

[Sharky]

Just checked: they're all rock-steady.

How is the granny ring attached?

 

[Gummo]

How is the granny ring attached?

Similar bolts - all tight. I'm beginning to think the rogue bolt that has rolled out from the adjacent woodpile - possibly left behind by the boyo who replaced the old chainset.

 

[Bristolian]

next question is where is its nut

Holding the bolt (oops, did I write that out loud?)

 

[Gummo]

I took the bike out for a ride. All having gone smoothly, I now believe my theory about the wandering bolt was correct, although I'm clearly culpable for the wild goose chase.

Many thanks for your kind advice and attention.