advice please

[Retribution03]

Did an 18 mile ride tonight with my 11 year old son and towards the end noticed this had come loose (see pic) does it just screw back on or is it a new part needed I'm not up to speed on the mechanics of cycles yet.
Cheers
Ian

 

[Retribution03]

Realise this may be in wrong section my apologies if it is
Ian

 

[Profpointy]

Did an 18 mile ride tonight with my 11 year old son and towards the end noticed this had come loose (see pic) does it just screw back on or is it a new part needed I'm not up to speed on the mechanics of cycles yet.
Cheers
Ian

we need the pic

 

[Garethgas]

Whatever it is, it's very small...I can't even see it

 

[Retribution03]

Oh yeah lol
Ian

 

[Garethgas]

Ah, just screw it back in. You'll need a special tool for that.
Be careful though, it's a fine thread and easily crossed so go nice and easy and it
should be fine.

 

[Retribution03]

Cheers Gareth he's only had the bike 3 weeks so ill take it back and they can fix it as I won't have the tool for it
Ian

 

[Garethgas]

Not only take it back but insist that they check the whole bike over,
pointing out that if they didn't tighten the bottom bracket, what else didn't they tighten?
Brakes? Wheels? Pedals?

 

[jefmcg]

Halyards?

Halfords?

(stupid phone!)

 

[raleighnut]

That's the lock ring.