Cycling UK Forum

I've a Steel framed bike on which one of the fork blades is further forward than another a LBS has advised me he thinks he can bend it so its parallel -its not a lot o ut maybe 5mm? Any thoughts ideas?

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Having cold set a couple of steel frames by 5mm each side of the rear dropouts ,my inclination would be that this is ok.Legend has it that bent steel forks could be straightened in a grid in the road.Has anyone done this? I completed a tour many years ago on a set of bent forks(hercules all steel bike).Handling was a bit wierd for a couple of days.2,500mls on them.

Over the years I have bent lots of steel items using something like a grid, but they have been items that require no accuracy. And you don't have complete control over where the bending happens.

I'd accept a frame that has been bent at the rear stays, if it looked okay, but I'd not really want to have to trust a fork treated that way. If a stay snaps you are likely just to have an unplanned walk, but a snapped fork .....

All fork blades are set for rake by being cold set, using a special former. 5mm is not a lot, depending on where it was bent out of shape and where you intended to bend it again. At least one professional framebuilder has commented that 'you get two or three goes at it' in relation to repairing slightly bent forks. I have re-set numerous sets of forks that were slightly out, without issues.

The trick is to apply the load to the forks in such a way as any new bending occurs where you want it to, without imposing high loads locally that will cause a kink to form. (I would not use a drain cover for this.)

The other thing that should be done is to keep an eye on the forks for some time thereafter; there is a small increase in the risk of the forks developing a crack.

Having said that, I have seen quite a few sets of forks that cracked, and I don't think any of them had been re-set.

cheers

As to what exactly happened I'm not sure I'm afraid. Its not an accident or anything similar.

I don't see why I shouldn't use the same LBS - hes provided more than satisfactory service in the past

I have a kink in my left seatstay, could I bend it back to straight?

Hi
Park Tool make a frame and fork straightener (FFS-2), as do VAR. Kinks in a uniformly round-section tube (your seatstay?) can be removed using a block with a correctly-sized hole drilled; the block is sawn in two and clamped around the kinked section
Regards
tim-b

tim-b wrote:Hi
Park Tool make a frame and fork straightener (FFS-2), as do VAR. Kinks in a uniformly round-section tube (your seatstay?) can be removed using a block with a correctly-sized hole drilled; the block is sawn in two and clamped around the kinked section
Regards
tim-b

Thanks very much, seems quite simple (I am not technical)
Is there any danger of damaging the seatstay while bending it back to straight? I only use the bike occasionally, it would not ride hands-free

After a crash which bent the fork back halfway to the down tube! and kinked the frame top tube, my mate and I bent his forks to be more or less parallel by using the gap between a gatepost and gate. We didn't dare bend them sufficiently to return to their intended position so turned them round by 180 degrees. We made it back to civilisation, walking down all hills for safety, since the wheel was very buckled. He bought new forks and carried on using the bike for a few years after, complete with kinked top tube.

Hi

Is there any danger of damaging the seatstay while bending it back to straight?

I guess that it'll depend on the metal used (it is metal? ) and whether heat is an advantage, our resident expert in material science will know far more about this
Regards
tim-b

cyclop wrote:Having cold set a couple of steel frames by 5mm each side of the rear dropouts ,my inclination would be that this is ok.Legend has it that bent steel forks could be straightened in a grid in the road.Has anyone done this? I completed a tour many years ago on a set of bent forks(hercules all steel bike).Handling was a bit wierd for a couple of days.2,500mls on them.

Not done it but aware of the "advice"

I was always under the impression that it was a "get you home" or "finish the tour" and use with caution type repair and not permanent fix.

gaz wrote:

QUIST wrote:Any thoughts ...

Without further information my thoughts are get new forks, possibly a new frame as well and consider using a different LBS in future.

What happened to misalign the forks?

Quite a misinformed over reaction!

As Brucey says, steel forks are regularly cold set, even on new bikes, it was a regular job when custom building. Sounds to me like the LBS knows his onions and what's the worst that can happen? It doesn't work so you replace the fork.

Cyril Haearn wrote:……….
Is there any danger of damaging the seatstay while bending it back to straight? I only use the bike occasionally, it would not ride hands-free

If you want to get the bike to ride straight no-hands, I think its far more likely that a minor mis-alignment at the front end causes difficulties riding no-hands than a minor mis-alignment at the back end.
Its quite straightforward to check frame alignment, using a piece of string....https://forum.cyclinguk.org/viewtopic.php?f=1&t=59332&hilit=string

Its quite straightforward to check frame alignment, using a piece of string....viewtopic.php?f=1&t=59332&hilit=string

That's neat. Is it true that the industry standard for misalignment on mass produced bikes is 2mm? E.g difference between head tube and a right angle from BB axis, Length from drop outs to BB axis.