Why can't I straigh...
 

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Why can't I straighten my rotor

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SRAM CL on a road bike. I can't set the caliper up right because the rotor isn't true (maybe as a result of a big crash a couple of months ago) and so it runs on part of the rotation.

I've had this many times before and with an adjustable spanner and a bit of patience have managed to true it back. And indeed I can do the same here too, and get it free running where it takes half a minute to spin down.

Then I go for a ride, incident free, and get back home and it'll manage maybe 5 rotations before stopping because it's gone off true again! It's knocking at least 100W off my power šŸ˜‰

Any tips - might take my plumbers blowtorch to it and then try straightening. Assume in the oven won't be hot enough. Or just get a new one?


 
Posted : 17/09/2023 11:48 am
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I've got about a 40% success rate with straightening rotars. I've made some worse than when I started.

If I can't sort it straight away I give up and buy a new one.


 
Posted : 17/09/2023 11:52 am
zerocool reacted
 bens
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I think if you get them hot enough and distort them, the metal will always want to spring back to its now deformed shape once it gets hot again.

I reckon get it hot enough again and then bend it back, it'll probably stay true


 
Posted : 17/09/2023 9:28 pm
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Or you'll crack it.

Hydraulic press might flatten it again, people with them swore by them back in the day. If you don't have access to one you would be cheaper with a new rotor.


 
Posted : 17/09/2023 11:02 pm
Posts: 3296
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SRAM do seem to make quite a lot of bent stuff. See my thread on a wobbly GX cassette…🙄


 
Posted : 18/09/2023 6:46 am

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