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Swapping some bits around this week and need to use a disc that's somehow become bent - enough to irritatingly rub on the caliper in one particular spot.
What's the best fix?
Don't have a vice, so is it a case of bending it back by hand?
Ta
new one.
Bend it back - carefully - with a clean adjustable spanner
A shifter if you have one. You don't even have to take the wheel off the bike. I've done this many times for small bends. Put something soft between the shifter and the disc though to prevent scratches and stuff.
adjustable spanner (with flat gripping surfaces) bit of card over disk do up spanner to clamp and then lever gently.
you can buy tools to do it but they don't do much more than the above.
you don't need to put much effort in - several gentle tries with a check betwen each one is the best approach.
+1 for a new one
By hand, no need for any tools
Unbend it- adjustable spanner as mentioned above.
If you want to get it 100% straight (most discs don't seem to be) then it's quite simple to lash up a runout gauge using bolts and brake mounts- you position the brake mount so that one of the bolt holes is over the disc's braking surface, then thread a bolt in so that it almost contacts the disc. Spin wheel, adjust bolt, and you'll soon learn exactly what shape it is. Slightly more faff but does give the best result.
ch-shing, ch-shing, ch-shing, ch-shing, ch-shing, ch-shing, ch-shing, ch-shing ad infinitum....
All you need to do is get an adjustable spanner then spend about an hour or so trying to straighten it, give up after making the bend considerably worse and buy a new one. HTH
Cool. I'll give it a whirl tonight and if all else fails just buy a new one. Ta.
Bend disc mean buy a new one
From experience, once it's been a bit bent,it will get out of true pretty easily in future, so you'll probably be buying a new one before long.
If it's crimped or creased (not entirely sure what the difference is, mind) then you're better off with a new rotor. If it's just slightly out of true, an adjustable wrench and a few minutes of tweaking will get it back to straight.
+3 BUY A NEW ONE!
IT MIGHT NOT BE NECESSARY!
It'll be fine. Just bend it back.