Stoptech brake question? - The Unofficial BMW M5 Messageboard (m5board.com)

XrayMD · 23rd July 2004, 03:06

I have Stoptechs on the front with slotted rotors. They've never felt quite "right". I've had them bled and fluid replaced twice but when slowing down from moderate to higher speeds (50 - 100 or above) the get a shudder in the whole front of the car. I don't have any problem stopping but it feels horrible. Any ideas? Dave Z. if you read this, I'm seriously thinking about taking a field trip to visit you so you can have a look, even though you're about 8 hours away!

gsfent · 23rd July 2004, 04:01

Quote:

Originally Posted by XrayMD

I have Stoptechs on the front with slotted rotors. They've never felt quite "right". I've had them bled and fluid replaced twice but when slowing down from moderate to higher speeds (50 - 100 or above) the get a shudder in the whole front of the car. I don't have any problem stopping but it feels horrible. Any ideas? Dave Z. if you read this, I'm seriously thinking about taking a field trip to visit you so you can have a look, even though you're about 8 hours away!

If it only happened after the brakes were installed, I would think something was not installed correctly. I had a similar problem with my stock brakes, turned out to be the thrust arm bushings in the front. You might try a local shop that does race car prep, they should be familiar with how to set up brakes. Or take that 8 hour drive, and while you are there.........

Regards,
Jerry

XrayMD · 23rd July 2004, 04:28

Aw Jerry!...don't leave me hangin'! While I'm there....what???!!!

MariettaM5 · 23rd July 2004, 05:10

I just installed a set of of front Stoptechs last weekend. I haven't bedded the pads in yet but they are already a significant improvement over stock; firmer pedal and no shudder at all. Going to a track event this weekend and will have a more comprehensive view after that but so far so good. Sorry I can't help diagnose your problem but but be confident that it doesn't have to be that way.

Redshift · 23rd July 2004, 05:31

95% of the time mine feel fine, but once in a while I get the same feeling you are getting. It's probably uneven pad deposition on the rotors themselves. Try re-bedding the pads properly and seeing what happens. Some pads are less compatible with the StopTech rotors than others. I had a similar problem on track with some of my favorite race pads, then switched to a different brand, re-bed the pads, and the problem went away.

Good luck and report back when you know more.

XrayMD · 23rd July 2004, 06:03

Thanks Brian... I have Axxis pads on there now but you have a good idea regarding the deposition on the rotors. One thing I heard was to put different pads on that are a bit harder and will serve to "scrub" off the deposition.

Redshift · 23rd July 2004, 06:05

Yep, that would be one thing to try, or you could just try re-bedding the Axxis pads. Let me know if you need more help - I ended up having to "rent" some Hawk Blue (very abrasive) pads from StopTech to get my vibration to go away, but I would like to see you try to exhaust all other options before having to go there.

Can you do me a favor and let me know if your brakes make a loud "clicking" sound when aggressively cornering? It may help to open the driver's side window. Mine is very annoying and I'm waitig to hear back from StopTech about it.

MIB · 23rd July 2004, 07:37

Quote:

Originally Posted by XrayMD

Thanks Brian... I have Axxis pads on there now but you have a good idea regarding the deposition on the rotors. One thing I heard was to put different pads on that are a bit harder and will serve to "scrub" off the deposition.

Hey Steve, WHICH Axxis pads do you have?

ChuckC, had Delux on and had the exact same problems and setup. I told him to go for the Ultimates, becasue they are the Ultimate.

He switched and is ALL SMILES now.

He had huge vibration, now its all sweet.

So check to see if you have Delux and if so switch to Ultimates.

I've had the Ultimates on all Four Stoptech BBK and they are sweet as.

Regards MJ.

atomic80 · 23rd July 2004, 08:20

I had the same problem on mine for a while. DZ attributed this to the pads not being properly bedded in and suggested that I "rebed" them with a series of hard brakings just as you would do when breaking them in. This worked in getting most of the shuddering but there was still some vibration that I didn't like. My dealership noticed that my pads were rubbing on the rotors due to a poor fit. After working with Stoptech they managed to get the left front pads to fit properly by sanding down the pads a bit. This solved the vibration/shuddering issue for me! Maybe this would fix yours too.

DZeckhausen · 23rd July 2004, 08:30

Quote:

Originally Posted by Redshift

Can you do me a favor and let me know if your brakes make a loud "clicking" sound when aggressively cornering? It may help to open the driver's side window. Mine is very annoying and I'm waitig to hear back from StopTech about it.

This one is easy. Your installer didn't bend back the rotor backing plate far enough and when you corner hard, there is just enough bearing deflection for the rotor to contact it. If you take the wheel off and shine a flashlight between the back of the rotor and the backing plate (sometimes called "dust shield") I think you will find the spot just in front of the lower ball joint is almost touching the rotor. Use a large screwdriver to pry it back a bit to gain at least a few millimeters of clearance.