Thanx for the reply and thanx again for the translation
but i think it's a good exercise for me to keep it in english.
Really? I didn't know that. I have had full floating brembo discs on my aprilia (SL1000) falco and you could hear them rattle. Since i didn't hear this sound on my 929 i assumed these discs aren't floating ones.
What's the use of aftermarket brake discs then? Besides the fact that it looks good...
I see you race with a 929 bladeracer
Do you race with stock discs?
During my last trackday my brakes stopped working at 130 mph (150 meters in front of a hairpin) due to fading so that's why i really want to make sure my brakes will work fine next trackday. Do you have any tips to prevent fading?
I allready have installed a radial brake master cylinder and steel brake lines and i have just bought carbon brake pads.
I just thought the translation might reduce the possibility of confusion :-)
Generally, the OEM floaters have slightly tighter rivets compared to race dics purely to reduce that rattling but they tend to drag more than less rigid discs. You can loosen them up yourself though if you wish but it's not recommended for road use. As the discs float around they can tend to knock the pistons back into the calipers. On the track you are constantly using the brakes so it's not a problem but on the road, it could be quite a surprise to come to the end of a long highway to find yourself rapidly pumping the brake lever to get pressure :-)
I think the aftermarket discs grew when OEM discs were tending to be stainless steel so they looked pretty at the expense of less bite. Cast iron discs are much more effective but tend to get surface rust very easily. Now most sportsbikes are running better quality discs but they can still be fairly heavy so as to last a reasonable lifetime of road use.
Race discs you can wear out in one season on the track.
Some may also provide a weight reduction which greatly improves frontend suspension feel but check actual weights before buying. EBC Pro-Lite's for example are heavier than the OEM discs. Axis do some very nice discs but they're expensive. You can also buy floating rear discs now which really just reduces the weight by running an aluminium carrier. Since I don't use the rear brake I make my own aluminium rear discs which are about one quarter of the weight of the OEM ones.
My racebike has stock brakes and suspension other than a rear disc I cut out of 5mm aluminium plate. Just the basic mods of full system and PC2
. My discs though are quite badly warped and are under minimum thickness but we only do sprint races so they still work fine.
Brake fade is a result of heat either boiling the fluid or glazing or warping the discs. When you change pad material you should scrub the discs thoroughly with brake cleaner to remove deposits of the previous pads.
As the discs and pads wear you get more heat as there is less metal to soak it away. That heat then boils the fluid which creates gas bubbles which ruins the fluid so it must be replaced. It should be replaced every year anyway as it doesn't last long.
When replacing the pads you should remove them and then use the lever to press the pistons _slightly_ further out of the calipers and give them a thorough clean with brake cleaner and some rag or very, very fine paper if the brake cleaner isn't sufficient but be careful not to remove _any_ metal as they are a close tolerance part. This will prevent damaging the seals as the new pads will press the dirty pistons deeper into the calipers.
I have tried carbon pads but didn't find any advantage at all. I generally run EBC HH's but I'll happily run whatever is on hand if I don't have HH's.