16 replies to this topic

[m3ap1]

I recently replaced my stock OEM rotors due to cracks surrounding the drilled holes with Racing Brakes front rotors. I went with RB due to the positive feedback on the forums. They were installed correctly and bedded properly on the race track following RB's bedding procedures. 

 

Issue I am having now is that when the rotors get warm/hot, my steering wheel shakes when I apply the brake pedal. When the rotors are cool, there is no juddering. The rotors were put on prior to my Laguna Seca track day last Saturday so they have a total of four 15 minute sessions. I would say I have to fight the steering wheel to make sure it is pointed in the direction I want the car to travel. I'm fairly confident using N05U pads but not with this rotor to pad set up. 

 

Has anyone ran into this issue before under extreme braking? If so, what was the fix to it? 

My goal is to have a non-juddering steering wheel under heavy braking. My past track car had Performance Friction BBKs on PFC11 all around and never ran into this issue. 

 

Brake Set up: 

Racing Brake 2-Piece Replacement Slotted Front Rotors

Endless N05U Brake Pads 

Stoptech SS Brake Lines

Castrol SRF Brake Fluid

 

RB's suggestion:
Replace N05U with a "right" compound. I am unsure what other pad I could try as N05U are used on Cup cars with success. 

 

 

Link to my track day for reference: 

https://www.youtube....h?v=-Xhc2TM6JK8

Attached Images

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Edited by m3ap1, 29 July 2020 - 10:26 PM.

[choerizo]

welcome to the forum!

 

the rotors do look like the bedding needs to either be redone or there wasn't enough heat/material transferred over. have you tried rebedding?

[Johnnypbmx]

Did RB mention what the “right compound” is? Did they provide any other advise besides seemingly that its your problem?

Edited by Johnnypbmx, 29 July 2020 - 01:07 PM.

[m3ap1]

Did RB mention what the “right compound” is? Did they provide any other advise besides seemingly that its your problem?

 

RB suggested I run a different compound and talk to my brake supplier for options. My brake supplier is very experienced in brake selection and noted that they have many customers run N05U with great success on heavy weight cars. N05U is a full race compound used on Cup cars with aggressive bite and high heat capacity.

 

Since RB wants me to run a different compound being that N05U is not up to par. What other pad compound could I try with similar or better characteristic that will work with RB rotors? 

Many owners from what I've read ran ME20, which is a grade below N05U so they will not be up to par with my type of track driving. 

[jhammergtr]

I do not have an answer, but I had the same problem with that combination. Long sequence of events, but ended up changing to brembo GT calipers, rotors and pads. Definitely great track setup, but very noisy even with softer street pads, track pads are unbearable on the street.

On stock calipers, My shudder started out with jhooks and endless me20. Went to n05us, still shudder. Put temp strips on calipers and they where close to max temp. Changed to RB rotors and a RB track pad with shudder.[looked like yours] Tried N05Us and still shudder, second set of rotors, still shudder. Only relief was endless mx72s which are not great on the track. Then shudder when track pads went in. Somewhere along the line, lost my brakes due to defective seals. Replaced seals and pistons. Multiple people tried breaking in pads. Cannot say enough about RB trying to help. Just did not work out with my car. Too many moving parts. Also changed front hubs/bearings I did a write up on current setup, but I do not know where it went too.

Hope you find solution quicker... cheaper...

[m3ap1]

I do not have an answer, but I had the same problem with that combination. Long sequence of events, but ended up changing to brembo GT calipers, rotors and pads. Definitely great track setup, but very noisy even with softer street pads, track pads are unbearable on the street.

On stock calipers, My shudder started out with jhooks and endless me20. Went to n05us, still shudder. Put temp strips on calipers and they where close to max temp. Changed to RB rotors and a RB track pad with shudder.[looked like yours] Tried N05Us and still shudder, second set of rotors, still shudder. Only relief was endless mx72s which are not great on the track. Then shudder when track pads went in. Somewhere along the line, lost my brakes due to defective seals. Replaced seals and pistons. Multiple people tried breaking in pads. Cannot say enough about RB trying to help. Just did not work out with my car. Too many moving parts. Also changed front hubs/bearings I did a write up on current setup, but I do not know where it went too.

Hope you find solution quicker... cheaper...

 

I really appreciate your feedback as it seems to point me into the right direction. I do not want to keep putting money into a rotor and pad combination in hopes to find something that is judder free. 

With regards to your Brembo GT calipers, what brake pad did you end up going with? N05U?

 

My current options:
1) Try a different rotor such as PFC/AP/Alcon using N05U pads

2) Go with a BBK such as AP Racing 9668/5000R

[haul s]

Have you considered adding brake cooling?

[m3ap1]

Have you considered adding brake cooling?

 

Yes, I've considered it and am looking into a solution. 

However, RB suggested to not run brake cooling on their rotors due to wanting to keep thermal temperature consistent. 

[Johnnypbmx]

Sounds like rb has a lot of what not to do but i dont know why they dont know a few pads that work with their rotors since seems like its a common issue- wonder if its the large channel design they use?

And how many people have a braking expert to consult? Haha im glad you did though!!

Im running top secret 400mm with endless mx72 f/r as i mostly do street driving. I was going to change to RB but had snobby responses from them when i asked questions via email. Im glad i didnt switch with this happening. I have solid bite with these but the alcon discs were the beat ive run so far.

Yes, I've considered it and am looking into a solution.
However, RB suggested to not run brake cooling on their rotors due to wanting to keep thermal temperature consistent.

[Johnnypbmx]

Sounds like rb has a lot of what not to do but i dont know why they dont know a few pads that work with their rotors since seems like its a common issue- wonder if its the large channel design they use?

And how many people have a braking expert to consult? Haha im glad you did though!!

Im running top secret 400mm with endless mx72 f/r as i mostly do street driving. I was going to change to RB but had Short/ snobby responses similar to what you got from them when i asked questions via email. Im glad i didnt switch with this happening. I have solid bite with these but the alcon discs were the beat ive run so far.

Yes, I've considered it and am looking into a solution.
However, RB suggested to not run brake cooling on their rotors due to wanting to keep thermal temperature consistent.

[99zipline]

I have been using RB OEM replacement rotors with ME20 pads. Not as good as RB XR70 pads (may not be in production anymore not sure) but ME20 work on track. Not the fastest out there but under 2:05 on 3 mile Thunderhill. Front straight 135+ and I trust them. No wobble under braking. 2015 BE stage 2 OTS tune. Toyo R888R.

[7racer]

I run RB but the ST carbon ceramic rotors.  That surface looks really uneven.  Can you run a more abrasive pad burnish that top layer then try it again?  I seem to remember something about their steel rotors needing a bit more to get a good transfer layer.

[jhammergtr]

For the brembo gt calipers I am using ST210 for street pads. I could not find the race pad series. The gt pads are smaller and thicker than stock size, see picture, but they stop better and run cooler than stock. In the process of looking in the garage, for the stock caliper, I have two sets of used RB pads (street almost new and track), used endless mx72, me20, n05Us.

Edited by jhammergtr, 30 July 2020 - 11:40 PM.

[descartesfool]

Run Hawk DTC60 or 70 pads. You need to get all that pad deposit removed from your rotors though. Very hard to get rid of once it's there. Take rotors off and have them cleaned using a rotary hone on both sides and that takes a long time. The re-install and bed them in properly following Hawk's instructions. I usually do 6 mediums stops from 100 kph to warm everything up and then 6-7 hard stops from about 120-130 kph and then drive 15-20 minutes to let rotors cool down. Rotors then get a nice even blue-grey color.

 

I use a Flex-Hone in a drill press to clean deposits off rotors.

 

Here is another option for removing brake pad deposits.

 

https://www.youtube....h?v=5qB-jnANdTw

 

And get some brake cooling.

[jhammergtr]

Thanks for the video. This looks quicker than only using abrasive pads. It took me over an hour per rotor with a 5inch orbital sander and green abrasive pad.

Edited by jhammergtr, 01 August 2020 - 09:58 PM.

[Warren-RB]

Track pads are more of a "personal" choice and preference, which is a "try & learn" process until it's settled to your liking which opinion can be subjective therefore we prefer to stay neutral w/o giving any recommendation.

 

By searching this forum you should be able to learn different opinion and feedback on almost all the named track pads used against RB rotors which we offer two different set up:

 

One is the stock replacement disc (re-use OE hats) like this member (see bottom illustration); and one is the complete rotor assembly with RB hats (center mount design-Top illustration)

 

 

[colo_evo]

Track pads are more of a "personal" choice and preference, which is a "try & learn" process until it's settled to your liking which opinion can be subjective therefore we prefer to stay neutral w/o giving any recommendation.

By searching this forum you should be able to learn different opinion and feedback

Ive read some questionable posts from you but this takes the cake.

Im guessing the type of brake the op is looking for is something that doesnt suck and will last more than 1/4 of a track day.

Edited by colo_evo, 03 August 2020 - 08:05 PM.