Tell me more ×
Bicycles Stack Exchange is a question and answer site for people who build and repair bicycles, people who train cycling, or commute on bicycles. It's 100% free, no registration required.
up vote 4 down vote favorite

I was hit by a car and now the steerer of my Reynolds 753 aero fork is bent.

Is it possible to bend them back? Would that be safe?

I can't afford a new pair!

share|improve this question
1  
I think this will depend on how bent they are. Are we talking 2 degrees or 200 degrees of an angle? – rally25rs Sep 14 '11 at 19:58
Welcome to the site, Tom. Interesting question! – Neil Fein Sep 15 '11 at 2:45
I would say they are about 10-15 degrees out. Interestingly, the actual fork blades/crown has not bent in the slightest only the steerer tube – tom Sep 15 '11 at 7:46
4  
One problem with bending any metal is it also stretches the metal, merely bending it back does not return it to the original shape. – Moab Sep 15 '11 at 15:58
My 1982 Fuju MX500 had a very slight bend in the steerer tube. I hit it against a concrete wall with a ruined wheel+tyre a single time and that seemed to fix it. – user5344 Oct 23 '12 at 21:35

2 Answers

up vote 2 down vote

I will tell you how I have 'fixed' bikes with crash-damaged forks in the past:

turn the bars round 180 degrees and swing the bike square on into a concrete wall.

Incredibly this 'technique' works remarkably well, and is quite fun to do with someone else's 'pride and joy', but, as of yet I don't think I have had the pleasure of using this 'technique' on anything above a Reynolds 501 fork. It works very well on 'hi-ten' but I have no idea about 753. But it is all steel, right?

Anyway, I share with you this 'technique' because, if you are going to try and 'bend it' then it works out a lot better than more 'scientific' approaches involving vices, scaffolding poles and such. The problem with is the tubes deform too easily so you cannot clamp them.

The only slight problem with the 'concrete wall' approach is that you can lack the will power to do it and any feeble-minded effort will result in pancaking the wheel. If splitting logs with an axe is one of your preoccupations then go for it. What have you to lose? (Well, the frame, the front wheel and your wrists...) But, as for the steel, it will bend back without too much fatigue damage, the hard part is actually doing it accurately. Hence the 'concrete wall' approach - tried and tested.

If you are a wimp when it comes to the 'concrete wall' challenge, also consider looking into getting a horrid cheap fork in chrome steel of some vague ch-mo flavour. You can get them for £25 or less and, if you were to ride your bike blind-folded you would be none the wiser that you had swapped out the front fork. Cutting down a fork to fit and getting the lower bearing race on is again not for the faint-hearted, unless you have the proper tools that is. I would recommend phoning round your local bike shops and seeing what they can do for you.

With an affordable fork in place you can look into getting some carbon fibre or 753 effort that will better compliment your bike.

Hope that helps and hope you are okay after you crash!

share|improve this answer
2  
P.S. Whatabout the car driver - aren't you claiming on their insurance??? – ʍǝɥʇɐɯ Sep 14 '11 at 20:20
6  
This seems like an incredibly risky procedure on something as important as a fork. I'm sure you've done it before and had no problems, but advising someone to do it with no idea of the extent of the damage and no way of inspecting the result seems irresponsible. – Mac Sep 15 '11 at 0:57
1  
I agree with the part about getting a horrid cheap fork. You can get entire used bike for $40. Just salvage a fork off an old bike. Most people aren't good enough that the fork is going to make a difference, and if you think you are good enough, then get your sponsor to give you a new fork. – Kibbee Oct 23 '12 at 23:56
It's really not that hard to chop a steer tube down. You can get yourself a cheap pipe cutter for a $15 and a metal file for a few bucks more. After using them both, you'll have a tube that looks like it came from the factory with absolutely zero previous experience. Hammering the star nut into it is the hard part, but the worst case scenario is that you have a few of them in your steer tube. It's a good thing to learn though and can really only learn it by mucking up a couple of them. You can cut it with a hack saw too and it'll be perfectly functional but wont' look as pretty. – jimirings Oct 25 '12 at 4:00
up vote 4 down vote

If by "steerer" you mean the top tube that turns in the bearings, it would be very bad for that to be bent, since it would seriously muck up the bearings, and ever getting it straight enough to NOT muck up the bearings would be unlikely.

Apart from the bearings, with something like a conventional steel fork the twin concerns are fractures in the steel and fractures in the welds and/or castings that hold everything together. Generally if the bend is ONLY in the length of the metal tubing of one or both fork tines, the likelihood of a fracture is pretty small. But it's so hard to be sure that there are no beginning stress cracks in a weld or casting that using the fork (with or without straightening) is risky.

If an attempt is made to straighten the fork, it's important that it be done carefully, in a way that will not put further stress on welds and castings.

share|improve this answer
I appreciate its going to an issue with the bearings, but thats not what I'm worried about at this point. there doesn't appear to be any cracks/fractures, but obviously the fact that the fork is bent means is past its yield – tom Sep 15 '11 at 8:16
2  
"there doesn't appear to be any cracks / fractures..." The problem isn't the cracks you can see; it's the small almost microscopic ones that you need a microscope / x-ray for. I'd vote for replacing it - the last thing you need is to have the forks catastrophically fail during a ride, dumping you face-first into the loving embrace of the pavement. – lawndartcatcher Sep 15 '11 at 12:40

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.