I just saw that you didnt have it apart yet... How did the old stuff on that wheel look? fine? Maybe check your install one more time? May need to rebuild the caliper seals and whatnot. check those caliper slides for binding
I read where rear MINI calipers need to have the piston turned (screwed back in) to get it to retract. Assuming you did this..... Maybe the one side hasn't fully rotated back out to where it's applying full pressure on the pad to the rotor.... It kind of sounds like this might be happening....
Look at it this way: If you let the next set of brake pads go for 80kmiles, they will DEFINITELY wear your rotors below minimums. If you're not replacing pads very often (or if you're not checking rotor thickness before then), you won't notice 'til it's too late. 80kmiles on the OE rotors and pads? Bite the bullet.
Jeff just bought this MINI from another member who happens to do a lot of interstate driving. He is addressing the brake issues with brand new rotors....
More backstory: So the original owner was a road warrior and racked up a good deal of miles driving. However, he didn't seem to brake veery often. :biggrin5: I have had the car for about 5000 miles and I am replacing fluid, lines, rotors, pads. (Just havent done lines and fluid yet). So the rear brake wear sensor is what tripped. The inside pad of the right rear was very minimal. The outside was better. The fronts hadn't tripped yet. Go figure. JCW Brembos, 85,000 miles and the fronts hadn't tripped the sensor but the backs did. I do have some pictures and will post them later that shows the condition of the OEM. But I will say that all 4 rotors were smooth. No grooves at all. I measured the thickness of both fronts and rears and while I was still above minimum thickness according to Bentley manual there wasn't enough left that I would leave them on only to do another job next year. I did use the brake tool to screw the caliper back in. Hard to tell tif the right was diff than the left. It seemed to be ok. Question, does the caliper bottom out and stop rotating? Should It? I don't recall that either of mine did. It appeared flush to the housing and wasn't making any more progress so I stopped.
Progress Made Another shout out to the folks at DetroitTuned!! I called them to explain my rear rotor not bedding in and was informed that the brake pads are in pair sets. :mad2: Who knew? So I never noticed but the pads are set as inner/outer. I ended up inner/inner and outer/outer. I corrected the mistake and took her for a spin and like magic the coating is coming off the entire face of the rotor. So, just because all 4 of your pads have cutouts for wear sensor cables it doesn't mean that you can just randomly install pads.
Look at it this way: fixing that is much cheaper than a new caliper. And you may very well have helped someone else avoid the same pitfall. I've made so many minor mistakes resulting in major consequences on my MINN that I'm seriously considering rewriting the Bentley manual. This little episode will be a worthy addition, but pales in comparison to some of the stuff I (and others) have done. There should be clips on the inner pad to keep it on the piston, none on the outer pad. It's very easy NOT to get those clips on properly, and it's not entirely intuitive on how to put the inner pad on--you have to slide it down vertically to get the clips to catch.
Well I thought some of you might like to see the condition of the old rotors so I took a few pictures. rears: Front: I am rather impressed actually. These are the original OEM JCW rotors off my 2009 R56 JCW. As stated before in this thread the original owner did a lot of highway miles, but not heavy on the stop/go so these lasted a good long time. They are still pretty smooth but they where close to the minimum thickness so that it was worth replacing at the same time as the pads. Here is a pic of the old rotor thickness: [/url][/IMG] And the new: I thought that the life of these was a pretty good example of the oem brakes, but then I read this post about a MINI owner that achieved 200,000 miles from his brakes http://www.miniusa.com/haroldqa/index.html
The way the caliper in the photos is used on the worn rotor will not provide an accurate measurement of rotor thickness without shims. A lip forms on the edge of the swept area, and thickness can vary from inside to out. A caliper or micrometer with posts is a better tool for reaching all points on the contact area. From the number shown in the photo, the rear rotor has a long way to go before being close to minimum.
Hey Jeff, looks like you'll have to put the original rotors back on. :smilewinkgrin: I'm amazed at how gentle the previous owner was on the brakes. Some folks just have mechanical sympathy & can really make things last.
True, a micrometer would have been better. This was for reference only plus I dont have a micrometer (time to go dig in Grandpa's old toolbox!!). The tool I used is notched so it gets past the lip on the edge of the rotor. Looking at the Bentley manual I see that the min thickness for the rear rotor is listed at 8.4 mm. Having mine at 9.06 mm gets me thinking that I was on edge. But maybe your point is that the new thickness is 10.0 mm and I am at 9.06 mm after 85,000 miles means I only consumed 0.94 mm which means I could have driven a few more miles for sure.