Rust on brake discs

[edgey]

Hey all,
Quick question about my brake discs, if the bike has been rained on, the next morning I can often come to it to find this kind of surface rust, wondering if there is a cure for such an occurance? It all comes off as soon as I use the brakes and doesn't affect braking, but would be nice if it could be prevented, can't really warrant (afford) new discs for such a mild problem.



Cheers.

[porndoguk]

they are cast iron discs thats why, vtr i believe?

2 options, buy stainless discs (but compromise on better brakes) or try swap them with somebody.

[edgey]

Aah, didn't even consider disc material...

These badboys are on my NC35, so I assume at some point someone has put iron discs on instead of stainless steel...
Quick searching tells me people prefer iron for track use for performance reasons?
This being my daily all weather road bike, I may consider changing to stainless steel in the future... Don't need track performance on the road.

Cheers!

[Neosophist]

Thers nothing wrong wtih that, car discs do exactly the same due to the material they are made of. Use the brakes and they will clean up straight away.

The material offeres good stopping power and is just a cosmetic side-effect, no reason to replace the disc

[speedy231278]

They look like exactly the same crappy EBC rust-o-matic Pro-lite discs that I had. Stainless steel road discs that rusted like buggery if someone spat on the ground a hundred yards away, and if they got actually rained on the pads would glue themselves to the disc so effectively I'd have to wallop the calipers with a lump of 4x4 to free them off. I'm glad someone else can back up my experience of this happening to discs which, IMHO, shouldn't do this considering that they cost well over a hundred quid each and come from a manufacturer which has a good reputation for quality products.

The good news is that the rust cleans up reasonably well, although after three or four years you'll notice the discs start pitting, and exceptionally cold weather can cause them to mildly warp. The braking performance will be unaffected as soon as the rust has come off, although I did find that if the pads needed freeing off the discs they left a nasty imprint of rust on the discs that took a lot of cleaning off, and gave feedback through the lever like the discs were warped until it had more or less gone. In fact, those marks would never completely disappear, and my old discs that are lying around somewhere still bear a number of faint marks on them.

Eventually, I was so annoyed with the things sticking to pads, and quite frankly looking like a pile of shit (the buttons holding the rotor to the centres discoloured and started to get surface rust on them too) that they came off the bike when they seemed to show signs of actually warping, after a trip out in -11C one rather chilly January morning this year. The cheap (less than half the price) presumably Chinese sweatshop steel discs I got from eBay have been out in the wet and the rain, and not a single rust mark has appeared on them yet. The EBC ones rusted the very first time, and did so every time without fail. Just a single drop of water falling on the surface would do it. If there was a very light passing shower and the bike was parked outside, you could tell the exact size of the raindrops from the bright yellow stains on the discs. Leave them overnight, and the yellow turned a very deep reddy-brown. Very, very unimpressed, and won't bother again.

[speedy231278]

Just managed to find my order for them. 11th April 2007 from ebcbrakesdirect.com MD1003LS/RS.

http://www.ebcbrakesdirect.com/search/d ... t=MD1092LS

If you search for VFR/RVF, you now get the choice of MD1003C or MD1003X (not handed).

Replaced the discs this June/July, although I'd be meaning to do so for over a year before I found some at a price I couldn't refuse.

[iDemonix]

I have the exact same discs and the exact same problems that speedy reports.

If I leave the bike in a cold garage for ages, or after a wet ride, the pads practically glue themselves to the discs and I have to put the front brake on, push down as hard as I can, then release the brake and try and rip the handlebars off the bike upwards. This usually frees it up and sends me flying backwards NC30 in tow.

[edgey]

When conditions are pretty harsh my pads can stick a little bit, nowhere near to the lengths you guys experience, mine dont need any extra force to move the bike, but just on initial movement theres a small 'crack' so to speak as they free themselves. Safe to say I'll probably keep these discs on unless things get really bad and keep my eye on them for wear now you guys mention really harsh conditions can warp them. A quick google tells me that yeah, these discs I have up front are EBC's.

[speedy231278]

I never had it with the OEM discs. They'd get a slight gold colour to them if they'd got wet,but the pads never stuck. Seeing as people who have EBC discs that aren't the pattern used by myself and others, I wonder if they changed the material when they came up with X and Contour discs? I'm sure if all their steel road discs had the rust issues that I've had, their reputation would be rock bottom!

[porndoguk]

if any ones interested in maybe swapping discs for wavy arashis let me know i have become unkeen on the wavyness and would like some VTR/RVF type ones with gold centres