RB Rotors

[Groundpilot]

As i promised i am going to talk about my impression of RB Rotors after the open track event at Thunderbolt NJ.
On a picture above you can see a pic of one of them. I took a picture with my iPhone right after the last track session before i mounted street wheels.
Second rotor looks exactly the same.
As you can see, they look fine, no cracks of any size, but if you look carefully, you can see uneven deposits of the brake pad material.
I use DTC70 pads for track days and i never had this problem with stock rotors and later with power slot rotors.
I think i know why did it happen. This was an open track event which means you go on the track any time you want but it also means that when you think its time to pit, there is no way you can do cooldown laps, because other cars are going at full speed. I usually like to do a few cooldown laps but i couldnt do it this time, wich i think contributed to brake shudder due to uneven deposit of pad material. By the time i got home, the brake vibration was almost gone as DTC70 pad compound is more abrasive at lower temperatures and they cleaned up my rotors.
This track is very technical with only one hard braking zone, which is at the end of the front straight. I was braking from 135 mph to about 65 lap after lap and i might have done more than 10 20 min sessions.
So, RB Rotors worked for me for now, but the true test will come when i go to the WGI, wich is brutal on brakes and everything else.

[pixelblue]

glad to hear they worked out. have your calipers turned yellow? takes a lot of heat to turn them yellow.

[GaryS]

Originally Posted by Groundpilot

[IMG]only one hard braking zone, which is at the end of the front straight. I was braking from 135 mph to about 65 lap after lap and i might have done more than 10 20 min sessions.

I guess time to cool down is the difference - unless Focused and I really did get a bad batch of rotors. At Summit Point I was braking from 135 to around 75 for turn 1, but I was also braking from around 95 to 45 going downhill for turn 5, so I don't think the rotors ever got a chance to cool down.

[Groundpilot]

Originally Posted by pixelblue

glad to hear they worked out. have your calipers turned yellow? takes a lot of heat to turn them yellow.

Front calipers turned yellow. Rears are still the same color.

[joeo]

Have you checked your dust boots?
Mine looked like this:

[Groundpilot]

Originally Posted by GaryS

I guess time to cool down is the difference - unless Focused and I really did get a bad batch of rotors. At Summit Point I was braking from 135 to around 75 for turn 1, but I was also braking from around 95 to 45 going downhill for turn 5, so I don't think the rotors ever got a chance to cool down.

Gary, i forgot to mention that i have stoptech aluminum pistons and i removed ti shims. They protect pistons and brake fluid from overheating, but keep pads and rotors a little hotter. My goal was to make new rotors work and i didnt worry about pistons. Castrol SRF fluid is next to impossible to boil in a 20 min session so i didnt think i needed ti shims any more.
Actually there are 3 more braking zones at thunderbolt, not as havy as discribed before, but still braking zones.
Maybe you and Focused did get a bad batch of rotors.

[Groundpilot]

Originally Posted by joeo

Have you checked your dust boots?
Mine looked like this:

Noy yet. I will have a chance to do it when i change front brake pads.

[icabod7]

Originally Posted by Groundpilot

Gary, i forgot to mention that i have stoptech aluminum pistons and i removed ti shims. They protect pistons and brake fluid from overheating, but keep pads and rotors a little hotter. My goal was to make new rotors work and i didnt worry about pistons. Castrol SRF fluid is next to impossible to boil in a 20 min session so i didnt think i needed ti shims any more.
Actually there are 3 more braking zones at thunderbolt, not as havy as discribed before, but still braking zones.
Maybe you and Focused did get a bad batch of rotors.

Where did you pick up the stoptech aluminum pistons?

[GaryS]

Originally Posted by icabod7

Where did you pick up the stoptech aluminum pistons?

http://www.1addicts.com/forums/showthread.php?t=441050

[Focusedintntions]

My rotors looked like that after a single day at vir, summit is just really hard on the brakes is what I've come to learn. OP check very closely in the groves and holes in there fore spider cracking. Also mind posting pictures of your pads? Do you run any ducting?

[Groundpilot]

Originally Posted by Focusedintntions

My rotors looked like that after a single day at vir, summit is just really hard on the brakes is what I've come to learn. OP check very closely in the groves and holes in there fore spider cracking. Also mind posting pictures of your pads? Do you run any ducting?

No ducting. Just brake shields mod. Hmm. Isnt vir hard on the brakes too?
I will look closely when i have time, but i dont remove pads untill its time to change them.

[Focusedintntions]

VIR has a couple hard stops, but there's plenty of time for the brakes too cool in between hard stops. I'm contemplating ordering another set of them to try out but I don't know.

[Groundpilot]

Focused, dont order them yet. Let me try them at WGI first. If RB Rotors survive that track, then they can survive anything else. I am not sure when i am going there, but i will report back when i do.

[Groundpilot]

Update. I went to Thunderbolt NJ yesterday with NASA, and tested my RB rotors again in 85 F weather. After beating on them in a very hot and humid weather, i am happy to report that these rotors look great, still no cracks at all, and i still have more than 60percent of DTC 70 front pads left after about 14 20 min sessions in two track days
I couldnt take any pics because my iPhone battery was dead.

[Focusedintntions]

Awesome to hear gp!

[BiscottiGelato]

GP. I am re-reading old threads, and noticed that you mentioned you had Power Slot rotors before the RB ones. Did the Power Slot rotors you got have the curve vanes as advertised? Power Slot claims that curve vanes are only applied in some applications. Wondering if this includes the 135i rotors. Thanks.

[e90pilot]

Ok I have a 325i with 135 brakes, RB Rotors, DTC70 pads. I got the spider cracking but it's just on the surface. It started at Laguna Seca which is extremely hard on brakes. I had been to Thunder Hill first which has some hard stops but after large stints of light braking so no cracking there. Not sure how much worse it will get. I'm just interested to see that some 135s aren't getting the cracks and you guys have WAY more power than me. I wonder if its as simple as just a bad batch.

I got the same hot spots on my rotor at first but they just went away eventually. Aside from the cracks the rotor surface looks good.

[pixelblue]

Originally Posted by e90pilot

Ok I have a 325i with 135 brakes, RB Rotors, DTC70 pads. I got the spider cracking but it's just on the surface. It started at Laguna Seca which is extremely hard on brakes. I had been to Thunder Hill first which has some hard stops but after large stints of light braking so no cracking there. Not sure how much worse it will get. I'm just interested to see that some 135s aren't getting the cracks and you guys have WAY more power than me. I wonder if its as simple as just a bad batch.

I got the same hot spots on my rotor at first but they just went away eventually. Aside from the cracks the rotor surface looks good.

file this one as an oxymoron

[e90pilot]

Originally Posted by pixelblue

file this one as an oxymoron

lol! What I was trying to say is that the wear and color are even. No big grooves hots spots or deposits. Just need to figure out how to stop it from cracking.

[Groundpilot]

Originally Posted by BiscottiGelato

GP. I am re-reading old threads, and noticed that you mentioned you had Power Slot rotors before the RB ones. Did the Power Slot rotors you got have the curve vanes as advertised? Power Slot claims that curve vanes are only applied in some applications. Wondering if this includes the 135i rotors. Thanks.

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