What is this supposed to do?

[Aerate]

Just taken delivery of son’s new Orbea MX 24 and there is a weird plastic bracket attached to the Seat post next to the chain. It’s not tight and can slide up and down the tube. What is it? And what should I do with it?

[Aerate]

Second shot for luck

[McFsC]

Chain guard I think? To stop the chain dropping off on the inside of the chainring and getting stuck and/or damaging the frame.

[GOATever]

Dog fangs catch the chain if it comes off of the chainrings, to prevent the chain from wedging between the little ring and frame. I can’t see the thing in your picture very clearly, but that could be what it is. If it is, it shouldn’t be loose though.

[anonymous-user]

Position it about half an inch lower than the chain and tighten it up, you can see the bolt clearly in the first picture. As others have said, it stops the chain coming off and getting wedged in the frame,

[neil-1323bolts]

Is that a single chain ring ? What's the chances of the chain coming off probably not much , just take it off , look better without it , take a gamble , live life on the edge !

[Marcellus]

being a single speed with a wide range on the back isn't there an increased risk of dropping the chain as the rear derailleur can't absorb the slack if the srping becomes tired or mucky?

So the bit on the seat tube is supposed to stop the chain jumping off if the chain is slack isn't it?

If so the correct position is almost resting on the chain I'd have thought.