Im going to be doing a brake job on my mini next weekend. I have read the directions from Randy Webb's how to and there is one thing I am unclear about. When you remove each rotor there are 4 torx screws and one retaining bolt to remove. However when you put the new rotors on you only have to replace the retaining bolt and can forget about the other torx screws??? I want to make sure I am clear on this....one retaining bolt will keep each rotor on nice and tight? Also i have heard a lot of people struggling in removing the torx screws...Some even have to drill them out? When they say this, they mean actually boring a hole through the screws right? I hope I wont have to do this. I do have an impact wrench so I should be Ok.. right?

 

Theres only one retaining bolt holding the rotor on. I was worried it wouldn't come off but it gave me no trouble. edit: also did that without a impact gun. I used a breaker bar, but it really wasn't required.

 

I just had the OEM brakes replaced with a Wilwood BBK, and yes the rotor is only held on with one retainer bolt. I guess it depends on where your MINI has lived--mine originally came from Wisconsin and everything is rusted--so an impact wrench was needed to remove it.

 

Ok great thanks fir the help....the fact the there are five holes in the rotors make it confusing in the pictures

 

Well 4 of the holes are for your wheel lug bolts to go past the rotor and into the hub, lol. The 5th one is the retaining bolt.

I'm holding the OEM rotor here next to my Wilwood rotors--but you can clearly see the holes I'm talking about. The hole with the beveled edge on the lower left of my hand is the retaining bolt hole. But I agree it is confusing--I couldn't believe the rotor was that simple to remove.

 

Now I get it! haha Thanks for the pic and your explanation....

 

Can someone post all the torque specs for the various bolts?

1. The 7mm allen front/rear
2. Retaining bolt front/rear
3. Pad carrier bracket

Thank you!!!

 

For GEN1 - regular brakes (not JCW)

Disk retaining screw 20 ft lb

Front
guide pin bolt 22 ft lb
mounting bracket bolts 81 ft lb

Rear
Guide pin bolt 22 ft lb
mounting bracket 48 ft lb

Haynes page 9.1

 

FWIW, my 13" and 14" kits don't have that retaining bolt. Not a big deal as the calipers hold things in place wheel off. I would however urge you to put some anti-seeze on both the bolt threads and the rotor to hub interface.

 

Thanks!

I was going to do a pad and rotor swap soon and I just realized that I have a stud conversion kit on the car. I am assuming that the studs will have to be removed before the rotor can come out. Are there specialized tools needed for this?

What is the torque spec for the stud conversion?

 

I wouldn't think the studs have to come out. This should be like any other car with studs. Just remove the caliper and bracket then the rotor slides off with the studs being retained in the hub.

 

Be prepared for a little extra time just in case you get one torx screw that is seized. I had one that would not come off and was forced to drill it out. I still need to go out and order some torx screws to replace it. My advice would be to buy some in advance and replace them anyway.

 

Thanks for the info - I will take a wheel off today and see what the studs look like. Hopefully they can just stay on.

Good to know that the torx screw might be an issue - I will try to pick some up ahead of time. I take it I can just get one in Autozone or some place like that?

Is the torx screw an absolute must? It seems the studs and the brake caliber would keep the rotor in place just fine.

 

It isn't a must. Its only purpose is to align the rotor with the hub threads for the wheel lugs to make it easy to put the wheel on.

I don't know if you can get them at autozone, but BMW shouldn't be an issue and they shouldn't be that much.

Just be prepared for the worst just in case you have to drill it out. You may not need them but having the tools ready will save you headache of searching for it all with the car apart.

 

give it a good soak with PB blaster and let it sit for 5 or 10...and be sure you have a strong arrangement with your wrench and keeping the wheel from moving as you attack the torx. Many have the wrench slip and the torx gets rounded and things go down hill fast. I use a scrap of re-bar threated 'tween two lugs to wedge the wheel from turning ( % )and a torx on an 18 inch bar pressing the socket into the bolt with one hand and turning the other and never had a problem...after some PB.

If you don't have stud conversion you can get the rear rotor off w/out removing the bracket...just the caliber, which saves time and effort as the rear bracket bolts are a little harder to get to. There's enuf angle to pop the rotor off the hub and gain clearance. But no huge issue to pull the bracket if you must.

And concur with cleaning rust and a lil anti-seize on the torx and the mating faces of the rotor and hub on reassembly.

Last - the torx adds no strength. As stated it is just an alignment/holding tool. All the similar bolts on the drums of my 79 disappeared long ago. The wheel holds everything together just fine.

 

Impact Driver. You can get one for under $20 and they work great. Just hit with a hammer.

 

Sounds great... what's the size of the retaining bolt?

 

Maybe I missed it in this message thread, but what is the size of the torx tool to remove the retaining bolt? I assume it is quite a large one? Thanks in advance.

 

I did mine a while ago, so from memory, I believe it is a T-50.

 

This is correct. I just did mine today. Took about 25 mins on the first side, and about 15 mins on the other side since I knew what I was doing lol... T-50 is the correct bit for the retaining bolt.

 

Certamus: any words of wisdom re: removing the superstructure which holds the caliper? How many bolts, etc.

While I just installed CT Bobcat pads, next time I probably will do the rotors as well. Thanks

 

Two bolts in the back. I believe it is 16 mm, again from memory.

Remove the brake pads first. Two 13 mm bolts but you may also need something to stop the nut from turning (17 mm).
Then remove the assembly that holds the brake pads. Two 16 mm bolts.
Then the t-50 torx bolt and remove the rotor.
Reassemble with antiseize on the torx and the two bolts. I use a little lock tite on the two pad bolts.
Torx T-50 torque to 20 ft lbs.
16 mm bolts torque to 80 ft lbs.

After the tire is off, perhaps 10 minutes each side. You may need a breaker bar and/or some rostoff or liquid wrench spray.

 

This looks about right... it's either 16 or 17mm. You really only need to remove one bolt. Just loosen the other a little bit and you can turn the mount far enough out of the way that you can get the new rotor on... It doesn't matter which bolt either, I removed the bottom bolt on one side and the top on the other just to see...

You will need to have the opposite tire on the ground or chocked when you remove the rotor retaining bolt. I didn't need liquid wrench or a breaker bar for any of this...

 

Many thanks for sharing the info re: removing and replacing rotors. I have perform this job on other cars but wanted to make sure I was on the right track. Thanks again!