Weird chain incident.

[Captain Scarlet]

Decided to go out for an hour or two tonight but only made it half a mile before this happened. As I started on a short incline straight into the wind I changed down to the small ring on the front, shortly after changing up on the rear when this managed to happen.





Resulting in me having to coast and push the bike the half mile home.

Thanks to my brother who called round and helped square the job up.

Eventually made it out in the gusting winds and managed a couple of PB's and even a top 4 on one segment on Strava.

 

[andrew_s]

Chainsuck!
The chain doesn't release from the bottom of the chainring and gets carried round. May be due to worn or damaged teeth. Usually it's the inner chainring, and the chain takes lump out of the chainstay.

 

[mjr]

Looks like a bad example. Were chainring or chain badly worn?

 

[Venod]

Chainsuck on the big ring, not as common as on the small ring, check big ring & chain for wear, check for tight links.

 

[Captain Scarlet]

I've done somewhere between 900 and 1000 miles since new.

Brother couldn't see any major issues with wear. First time it's ever had an issue when changing gears.

 

[Cycleops]

Can't see any wear on the chainrings/cassette so looks like it's some sort of problem with the rear or front derailleur.

 

[mjr]

If nothing else, it looks like you've a scratched tooth on the big ring now :-( Was the chain lubricated and you reduced pedal pressure while shifting? It seems a bit of a puzzle why it didn't release from the big ring but I'd not worry about it unless it repeats.

 

[Mile195]

Nasty. I did that a few years ago and it bent the front derailleur beyond repair.

I always take the power off completely when I change chainrings these days to the point where the bike is only freewheeling to avoid a repeat. But like everyone has already said, sometimes it's just bad luck and physics, but the majority of the time worn parts have usually played a part.

 

[Arjimlad]

My son's bike did this so it's helpful to have explanations as I was baffled. The chain isn't badly worn nor are the chainrings. I think it was a tight link or two on an under-lubricated chain.

 

[Deleted member 1258]

Worst case of chain suck I think I've seen, strange that it happened on a bike so new, I've only had it on very old very worn bikes, perhaps a problem with the front changer?

 

[cyberknight]

Whats the gap between chainring and mech normally , hard to tell from the piccie but it normally is about 2 mm i used to get chainsuck untill i set my mech height properly.