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I recently had a low speed spill on my bike leaving the brake lever rather bent. Can I bend it back (roughly) straight or it is likely to just break? Given that it is cast aluminium, I suspect is will fracture and break.

Any experiences out there with this?

If it is doable, how sould it be done? Vice+rubber mallet? Vice+pliers? Anvil+hammer?

  • Replace it! Similar experience with a bicycle brake that later snapped leading to a (minor) accident. On a motorbike this could obviously be far more calamitous! – Miller86 Jan 7 '16 at 11:05
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It is possible that it would break. However i think that buying a new one shouldnt be expensive and is the best solution.

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  • Cost is about $120 and I only replaced it a few months ago when someone tipped my bike. I might experiment with the old one and see what happens. – dave Apr 6 '11 at 17:47
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    +1 on replacing the lever, even with the expense. Aluminum fatigues with even the slightest bending. I would not trust a severely bent lever for such an important task. Disclaimer: I am not a metallurgist. – William Cline Apr 6 '11 at 21:39
  • @dave $120 for the lever alone?! Or including labor? You didn't mention the make and model of your bike, but I'm having a hard time finding anything in that price range. – jensgram Apr 7 '11 at 12:39
  • Triumph + Australian prices = $120 :-( That being said, I have not looked around at 3rd party options. – dave Apr 9 '11 at 18:48
  • Almost certainly going to break while bending it back. – Brian Knoblauch Jun 2 '11 at 17:30
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Don't try bending slowly with pliers - I've experience with levers bent in racing tumbles to tell me that cast aluminum doesn't like that.

What has been suggested to me is heat, multiple swift whacks with a heavy mallet, and don't try to get it perfect - get it close to where it was. I've done one or two that way, but not been happy with the result.

In the end I've always used a replacement and kept the bent in the spares bin.

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  • I've had just the opposite experience with bending slowly. I used vice grips to make a bending-pivot-point on the hand grip and length of pipe to go over the lever for leverage. From what I hear it was just luck as they usually snap. Also depends on how far they've been bent and the quality of the lever. +1 for replacement when in doubt. – aportr Nov 29 '11 at 3:18
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Applying Murphy's Law, yes, it will break and, worst, it will break when you most need your brakes. rimshot

Seriously, think of what would happen - in a bad situation, you're going to squeeze that lever as hard as you can. A fatigued part is most likely to fail under stress and the consequences in this case would be literally fatal.

I would never drive my car with a suspect brake pedal. I think you're dealing with a parallel case. Please get it replaced.

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Yes, it can.

It's cast aluminum. It may have an anti-oxidation coating on it.

If it does, you'll need to eat it off with aircraft paint stripper or a parts dip first.

Then, heat it up with a torch, not too hot, and slowly bend it back into shape. Take your time.

I've done this for my kid on his dirtbikes, which he constantly dropped and his road racing bike, which he constantly crashed.

I've never had one break after doing this due to use. I've had them break as the bike tumbled down the track though. Good luck.

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1) First buy a new one, no trick is fool proof. If you are successful you have a spare. If not, you can still ride and wait for the next bender. 2) Rub the area of the bend with a wet piece of soap. 3) Heat the lever on a gas burner until the soap is shiny dark brown/ black. This is to soften the duraluminium. (or duralumin if you say so) 4) Throw it in a bucket of cold water. 5) Use a plastic, or hard rubber hammer on a trunk of wood or a block of lead to straighten it back in shape. Or bend it back in a vice. Or both. 6) The hardness will return after some days but the soft lever is strong enough to use.

I have bent one lever 3 times back to the original shape.

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    Aluminium (and copper) will soften (annealing) after heating and rapid cooling, the soap is just to indicate the required heating temperature. – stamper Aug 5 '16 at 4:27
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This guy seems to have developed a way of solving the issue without using a blowtorch. Not sure if works with an aluminium one and how the metal likes it though, I guess it makes it more susceptible for breaking sooner

  1. Park your car on a flat area
  2. Place a rag or piece of fabric on the floor, close to the one the tyres
  3. Make sure it's safe and put the car on neutral (N)
  4. Place the lever on top of the rag and move the car so that the edge of the wheel starts to roll over the lever, unbending it with the car's weight
  5. Carefully repeat number 4 until the lever is back to it's original form

I guess if you use some sort of heating combined might work better

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