Can a brake rotor be straightened?

gog

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As much as it shames me to admit, I recently forgot to remove my disc lock before driving off. Wheel managed a whole rotation before the lock slammed into the back of the slider and did what you might expect it to do. Now the disc has an area of about 1mm 'wobble' causing a slight rub on the brake pads and quite a noticable vibration on braking. Im not riding again until its sorted.

I posted earlier asking if anyone had a replacement, but as it seems im out of luck there, can these be straightened in a vice? I know bending a bit of metal back after it has been bent one way cant be good for it structurally, and if it wasnt such a slight warp (or if i was slightly more flush at the minute) I would certainly bin it, but any input appreciated.
 
You can get them reground but buying a new replacement is your best bet.
 
As much as it shames me to admit, I recently forgot to remove my disc lock before driving off. Wheel managed a whole rotation before the lock slammed into the back of the slider and did what you might expect it to do. Now the disc has an area of about 1mm 'wobble' causing a slight rub on the brake pads and quite a noticable vibration on braking. Im not riding again until its sorted.

I posted earlier asking if anyone had a replacement, but as it seems im out of luck there, can these be straightened in a vice? I know bending a bit of metal back after it has been bent one way cant be good for it structurally, and if it wasnt such a slight warp (or if i was slightly more flush at the minute) I would certainly bin it, but any input appreciated.

well it's not recommended, but what harm can trying do, some one must have done it in the past, I would replace it if it was mine though!
 
Cheers. I did expect that replacement would be most people's response. Theres a pair of used undrilled iron discs on ebay just now which should fit - anyone know if these are any good vs standard drilled steel mono discs? looks to be a bit of lip on them but likely better than what i have just now.
 
for what bicke du you need it ! I have a 300mm one with adapter for g/s up for grabs
 
We regularly straighten our mountain bike discs. I would think that an engineering shop with a surface plate and press should be able to sort it out.

Did you fall off when it happened. Embarrassing if you had an audience.

I have a hi-vis flexy coil which gets looped up and around the front brake lever to remind me about the disc lock.
 
Been there, done that! Try a local engineering company if you want it straightened but I'd certainly echo the above in favour of a new disc.
 
litelfun it's a 1986 R80RT mono, dual front disc setup.

I managed not to fall, front slid out but caught it. bit of shoulder strain but no damage except the rotor. ego escaped too as it was dark and no one else around :D

I have the hi-viz loop but hadn't been using it, lesson learned I suppose.

replacement it will be.
 
I personally would not recommend cast discs as this is what they will look like ( seriously ) just one day or so after use !

I think they were an idea of the 80's ( bit like twin sparking etc ).
 

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I love cast iron discs... :rolleyes:

<table style="width:auto;"><tr><td><a href="https://picasaweb.google.com/lh/photo/JHSD5iyAXOao4L5cfrgZ7MNrOPp0J9VjAYACV_X6MiA?feat=embedwebsite"><img src="https://lh3.googleusercontent.com/-CWgBX0FhPKs/Ugvvf98kRfI/AAAAAAAACNA/jragO3SDGW0/s400/DSCF0787.JPG" height="300" width="400" /></a></td></tr><tr><td style="font-family:arial,sans-serif; font-size:11px; text-align:right">From <a href="https://picasaweb.google.com/110392685136049648662/GuzziBoxRebuild2013?authuser=0&feat=embedwebsite">Guzzi 'Box Rebuild 2013</a></td></tr></table>

you might get away with a skim :nenau - but i would try Steptoe for a reasonably priced decent disc. ;)
Good Luck
 
The main reason cast iron is not used (unlike 99% of cars) on motorcycles is purely asthetic. They do look unsightly until the first sweep of the pads, but things move on and we vain lot like our bikes to look pretty. :cool:
 
Cast iron does stop better than stainless.

in the dry - yes.
in heavy rain, the cast iron discs on my Guzzi can have an almost 2 second delay as the water/rusty slime (?) clears off before actually working!
This could give one laundry problems if not expected.
Maybe it's just a Guzzi thing, but i doubt it.
 
The cast iron discs are an extra security feature, the longer they are left, the less chance of someone pushing it away! :P

What's the Italian equivalent of the Spanish manana. Sounds like it applies to brakes too.:)
 


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