[bladeracer]

The disks are stainless so they should be very rust resistant.

Are they really SS?
That's a step backwards.

 

[bladeracer]

You can get different grades of SS (like with kitchen knives)
I thought most current bikes used SS. Although my Yam XTR doesn't cause I get rust deposit inside the drilled vent holes.
You say step backwards compared to? cast iron? carbon?
I've only been riding for 7 years so I don't know what the common material used was before that

High carbon iron is the best and it does show surface rust very quickly.
Stainless was used years ago because it doesn't rust.
Do mean that you assumed your bike has SS discs?
I'd be surprised if any sportsbike runs SS discs.

 

[bladeracer]

It is what I was told by my Honda mechanic on my previous VFR-03 & current RR8
And to add to what they say, I don't experience any rusting on the discs.

I don't know about the exact content of the metal but you add different alloys to the metal to turn it into stainless.

I guess you could add carbon to the mix to improve friction but slightly increase wear.

A while ago I read a mag article about pads & discs when I was needing new once. It said most modern bikes use SS discs, the chrome content unfortunately reduces friction!
You are probably referring to ductile cast iron discs with the typical surface rust. They are better for performance/ track use but rust & probably heavier

I wouldn't be surprised if the VFR has SS discs. My brother's '02 has terrible brakes.
Did that article list any modern sports bikes that have SS discs?
I doubt the iron discs are heavier but they are certainly better for braking performance - regardless of whether road or track. All my modern bikes have iron discs - ZX6R, GSXR1000, '98/'90/'85 GSXR750's. Even the '84 GT750 touring bike has iron discs.

 

[bladeracer]

No, like I mentioned the article said MOST modern bike. It certainly didn't list discs fitted to all the bikes since 1980's.
Also your idea of modern may be different to theirs or mine.
I would consider less than 10 years old, modern but accept that it is all relative as there are no specific rule for classification!
For me, the brakes on the VFR were excellent specially the linked system.

As to find out exactly what metal is used on each modern sport bike, you'll have to do the search!

Slightly off the topic have you had any running experience with DOT 4, 5 & 5.1. I know the basic characteristics: boiling temperature, moisture absorption and not mixing 5 with 4 & 5.1. I also heard from somebody who used 5 in his racing car who said it was crap (long time ago so can't remember the details)

I figure bikes became "modern" in the mid-eighties when Suzuki invented aluminium frames. I guess it could be claimed they stepped up again in the late nineties when they started injecting them but I don't consider that to have been a huge leap forward..
You stated the '08 discs are SS, I merely asked you why you thought that
I've never used 5.0 and never will.
I generally use 4.0 and 5.1 if I had a problem with the brakes which is very rare. I've never had any problems mixing 4.0 and 5.1.

 

[bladeracer]

As I mentioned earlier, the Honda mechanic told me what the disc material was and the fact that my discs don't rust add to this what the mag article wrote. I am not Sherlock Holmes but hey that is what I figured out.

If you do find out this is not the case for RR8, I would be interested to know.
I also mentioned before, you get different grade of SS for different application.

Are your discs magnetic?
Sure, there are different grades but what is the relevance here?
SS discs (regardless of the alloy properties) don't work as well as iron discs.

 

[bladeracer]

Sot sure it this was a joke
But don't be surprised to see electro magnetic braking system on motorbikes in the future (unless they already exist)
My point about cast iron was not about their performance but their rusting.
I did say they were better in terms of performance.

By changing the content of what goes in SS you can change their properties, therefore application.
As an example, cooking knives, you get surgical grade which are used to make cheap one with sharp edges which last a long time. Once they go blunt it is very difficult to sharpen them again
Then you get the high carbon SS knives, much more expensive, looses their edge quicker but can easily be sharpened; most pros use these
Marine grade SS are the most corrosion resistant grade.

But SS can also be brittle depending on its constituant

Stainless steels are often very poor magnetically, especially when compared to iron.
I would assume that stainless discs would be made from whichever alloy offers the best braking performance ahead of any other considerations.