Bent seat stay

[Chris S]

Last week my bike was hit by a car which bent the seat stay by about 2.5cm. The bike has a steel frame and I reckon that I could get the bend out using a jack. Is it worth trying this or is it likely that the metal has been seriously weakend by the impact?

 

[roubaixtuesday]

Claim for a new bike from the motorist would be my advice.

 

[Drago]

Yeah, make them pay.

 

[si_c]

Claim for a new bike from the motorist would be my advice.

This is the right answer.

The metal has already been weakened by the impact, you can bend it back, but it won't have the same strength. Another option would be to have the stay replaced by a framebuilder, but this will cost several hundred pounds.

Either way, you should be claiming against the motorists insurance.

 

[fossyant]

Claim. I had a 531c bent back by a frame builder but it was possibly only 0.5cm out

 

[presta]

Claim for a new bike, but you don't have to spend it on a new bike just because you've been paid it if you can repair the old one.

A jack won't do it because the metal work-hardens when it bends first time, and then bends in a different place second time around unless it's trammelled. Jack it and you risk ending up with a double bend.

 

[Ajax Bay]

What the OP doesn't share is that it was his (naughty) car that backed into the bike in the garage. [/pink/]
Given that steel is real and can cope with 'work hardening' no probs, I reckon they could straighten it (does it matter if it has a double bend?). The key requirement is that the dropout is perfectly aligned with the other so the wheel runs dead centre. One doesn't know whether the seatstay bridge integrity has been affected.
From the image, that frame has given a full life of service so this bend is its way of telling the OP to move on.
Another steel frame (unbent) might the way to go - my local tip regularly has steel bikes of this vintage (components have suffered but frame fine).

 

[Chris S]

Claim for a new bike from the motorist would be my advice.

My bike's market value is about £30. It's not worth the hassle or the wait.

 

[Ian H]

Given that an illustrious frame-builder of my acquaintance (no, not that one) stated that steel fork blades could be safely straightened around three times, I can't see any issue with straightening the stay. Alignment can be checked by seeing whether the wheel rim/tyre is central between both sets of stays.

Ignore this advice if you really want a new bike.

 

[T4tomo]

My bike's market value is about £30. It's not worth the hassle or the wait.

Plus his Mrs said he shouldn't have bloody left it in the way so, no she will not be buying him a new one.

 

[Sharky]

Jack it and you risk ending up with a double bend.

Go for it and get some "Hetchins" transfers for it.
Will be worth a small fortune.

 

[presta]

steel is real and can cope with 'work hardening' no probs

Steel 'copes' with work hardening just fine.
Your problem is that the original bend becomes harder than the unbent material, so if you try to bend it back again without forcing it to bend in the correct place it'll preferentially bend somewhere else, because the metal bends more readily where it's softer.

 

[fossyant]

You'll need to carefully brace the frame so you don't introduce any additional bent tubes. Just be mindful you don't damage the seatstay brake bridge

 

[Chris S]

I got the bend out using a jack. There is now a slight wobble in the seat-stay but the dropouts are at the same height. Now I've just got to wait for the swelling on my knee to go down so that I can ride my bike and see if it still steers straight.

 

[fossyant]

Does the rear wheel sit in the centre ?