I have a 05 stock S version that the rear tires keep feathering. I bought the car with 45K and the set that was on it started to feather after I drove it for awhile. The second set on it now is also feathering and the car has 90K now. I am planning to change the rear struts as I know that could be a possible cause. Any other thoughts as to what to look for? Car has not been wrecked so everything should still be straight. Any thoughts on reasonalble struts as this is a daily driver for my wife?

 

Have your alignment checked. I would do that before throwing parts at it.

 

Sounds like you just have worn parts but I wouldent condem the struts as your solution just yet. The springs are probibly settling. Struts may be worn with 90k miles but replacing them will have little if no affect on fixing your problem. If the tires are feathering on the inside, there is not much back there to adjust to compensate for it. More than likely, the bushings in your arms are worn out caulsing your tire wear problem. IMO, I would get some replacement arms with from Helix, Alta, or WMW. That will give you adjustability you need and upgrade the bushings at the same time. I would not recomend replacing the rear struts without changing all four on a car approching 100k miles.

 

MINIs are set up with some negative camber. The reason is to improve handling characteristics in cornering. negative camber by its design is going to create some feathering of the inside tread. Rotating tires more frequently will help to even out the wear.

 

Negative camber is IMHO not going to cause feathering. In 87,000 miles of driving my MINI I have never had feathering of the rear wheels. More wear on the inside yes, feathering no. While it is possible that worn parts are causing the feathering my guess is that the alignment is off. Too much toe-in can cause the feathering.

 

Correct me if I am wrong but I dont think R53's have any rear toe adjustment. The typical alignment shop is going to try and sell you on that, their mind set is "set the toe and let it go". That may work on the front but not the rear of an R53. Also, make sure the alignment shop is giving you a full thrust angle/4 wheel alignment where they check all specs by doing a full caster sweep, checking the thrust line, and SAI (steering axis inclenation). Especially if you have never installed front strut reinforcement brackets. I am sure you have heard this before if you've had you car for 90k miles- R53's are prone the front strut towers mushrooming after contact with hard road bed object like pot holes. A true full Mini alignment will also require the suspension to loaded by putting measured weights in the seats and I beleave a full tank of gas. Ask your alignment shop they check the thrust angle and SAI. If they dont know what that is, find another shop that does. As I stated prior, if you dont install a set of aftermarket arms you will not have full adustability of the rear suspension. The parts on your rear suspension that affect the specs you are discribing (toe and camber) are the rear suspension arms. The factory ones are very flimsy and the bushings wear out easly. Replace them and you will be able to accomplish two things: the alignment shop will be able make adjustments to compensate for other worn parts and, you will have a better handling car when you replace the crappy factory arms.

 

The control arms, or wishbones, adjust the camber.

The toe adjustment, to correct the feathering, is made at the pivot point of the trailing arm.
I think the mounting bracket is the adjuster but I'm not positive.

Hope this helps...

http://www.realoem.com/bmw/showparts...86&hg=33&fg=30

 

I liked your post especially the part about the mushrooming. I have been frustrated as hell with tire rotation, alignments and replacements that I literally gave up. Every time I went to the dealership they give the same song and dance about aggressive camber. This time, however, after driving the car over 75,000 miles they tell me about the mushrooming. Claiming it is my fault. I do not doubt the fact that I have hit a pothole or two, but I must have mentioned it 20 times and only now do they tell me about the mushroom effect. I have dropped so much money on the tires it is mind boggling. They say the only fix is body shop. Is this the only fix that you know of...?

 

My rear tires were wearing badly with negative camber (worn inside edges). the alignment shop could not get the rear lined up because of what they claimed was a bent rear control arm (the one that controls the camber). I replaced them with TSW adjustable rear arms and that allowed them to set it to factory spec, which is still agressive and wears the inside edges rather quickly and requires frequent rotations.

 

If you are running more than 1.5 neg camber at the back you have too much.

The feathering is caused by the toe being off. This can be caused by a bad lower control arm bushing as it will allow the wheel to change its toe setting while driving.

 

I have a '06 Cooper S with 17" rims. I purchased it about a month ago with 41,000 miles. It's all stock. The front tires were wearing evenly. The rear tires (Goodyear run flats w/17,000 miles on them) showed signs of cupping on the inside of each tire. The left rear was pretty bad. The right rear just bearly noticable. After rotating the tires, I took it in for a 4-wheel alignment. The mechanic told me that the toe for each of the rear tires was in too far (which would explain inside cupping) and there wasn't enough adjustment on the left rear to bring it into proper specs. The toe for the left rear was at .32deg. Mini says there should be .13-.27deg of toe for the rears. The right rear was at .28deg.

After the alignment, the left rear was at .29deg and right rear at .26deg. There was no adjustment left for the left side, but the right side looks like it could be adjusted out more if needed. The car was never in an accident because I know the previous owner. If I replaced all 4 control arms I know I'll be able to adjust toe & camber, but do you think I need to replace the trailing arm bushing too?

Any reason, other than the bushings, why the left rear would not be able to be adjusted out far enough?

Camber on both rears were at -1.9 before & after alignment. The range per Mini is -1.4 to -2.1deg.