Derailleur Damage

It looks as though my bike may have occurred some damage to its derailleur and/or hanger.

Can anybody tell based on the photographs I have attached?

I'm not sure how it happened but it looks bent to me and the gears are not changing smoothly.

I've read that it's not too hard to straighten the hanger with a tool like the Park DAG-2 but would you leave it to a bike shop to sort out?

Thanks in advance.

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looks bent to me though i can't tell whether the hanger is bent or the mech itself -
that is one of the few things i would take to a decent mechanic to fix.

The hanger is bent, or possibly the whole dropout. You can bend it back, carefully, with a big adjustable spanner. Be very careful to get it straight and not to adjust the rear spacing or the angle of the dropouts.

There's not much point in taking it to a mechanic - you're no more likely to snap it off than they are. The only difference is that they might have a jig to ensure that the derailleur hanger is in precisely the right position.

If it snaps, it snaps - unlikely, though, and you can always get it repaired by a mechanic.

Take it to a mechanic. If you have to ask for the forums opinion then you obviously need a professionals help. You could take a spanner to it but why bother when £5-£20 will easily cover the repair and have it set correctly rather than guessing by eye and risking snapping your non replaceable hanger off. Any decent mechanic will easily fix that in about five minutes. As a full time employed mechanic myself I know as I see this kind of thing all the time. Without the correct alignment tool, your gears will most likely never work properly again.

Thanks for your replies. I will take it down to the bike shop to get it sorted. I think it's good to have an idea of what you need before taking it to an expert hence my question to the forum where I know there are knowledgeable folk who are happy to share their opinions.

Oh balls do you need to take it to a mechanic - I say that as an ex-mechanic myself. If you can't get it right by eye, the tool is easy enough to make. £2 in materials + half an hour of your time beats £20 labour charge and an afternoon waiting to get your bike back.

Oh balls do you need to take it to a mechanic - I say that as an ex-mechanic myself. If you can't get it right by eye, the tool is easy enough to make. £2 in materials + half an hour of your time beats £20 labour charge and an afternoon waiting to get your bike back.

How the crap are you gonna make a derailleur hanger alignment tool in half an hour and with £2 of materials?

If that came into my workshop I'd most likely do it there and then because it's a 5 minute job and I'd probably do it for a donation to the cake/beer fund, not £20.

Bit of angle iron cut to a little over half the radius of a 700c wheel. Drill two holes in it - bolt one side to the derailleur hanger, put a bolt in the other side and screw in/out to act as the 'feeler'. Works fine, if a little clunky. If you bend a lot of hangers, then I'd suggest buying the proper tool.

I didn't say that all workshops would charge £20 and require booking - independents wouldn't, but take it to a big retailer and they probably would. All I said is that it's possible to do it yourself with basic tools (hacksaw/drill/nuts and bolts). I know DIY isn't for everyone, but it's not absolutely necessary to take it to a shop.

Where's your workshop Mr Vandal?

Where's your workshop Mr Vandal?

Glasgow!

Bit of angle iron cut to a little over half the radius of a 700c wheel. Drill two holes in it - bolt one side to the derailleur hanger, put a bolt in the other side and screw in/out to act as the 'feeler'. Works fine, if a little clunky. If you bend a lot of hangers, then I'd suggest buying the proper tool.

I didn't say that all workshops would charge £20 and require booking - independents wouldn't, but take it to a big retailer and they probably would. All I said is that it's possible to do it yourself with basic tools (hacksaw/drill/nuts and bolts). I know DIY isn't for everyone, but it's not absolutely necessary to take it to a shop.

Fair enough, I'd still say take it to a bike shop because it'll be a better job but then, I did just tweak the hanger on my pomp into shape at home the other day with an adjustable spanner because I couldn't be bothered riding up to the shop!