[Raymondo1234]

I switch out the msport brakes to mperformance red ones on my m235 xdrive. I also switched to mperformance discs and pads.

Even after adjusting the handbrake as far as it will possibly go, it's still not engaging, almost like it is not going to lock onto the wheels.

Do I need to change something else for this to work?

Thanks in advance.

[aerobod]

After switching the rear discs, the parking brake shoe pawl in the "hat" of the rear discs will need to be adjusted through one of the bolt holes. Often when the old discs are removed, the adjusting pawl has to be backed off to allow the old disc to be removed without the shoes catching on a ridge of rust and has to be readjusted to the new disc. The pawl is normally adjusted to about 7 notches from locking up the disc when the parking brake is off.

[pikcachu]

you would think the new disc would not fit unless you back off the adjusting screw... not the other way around no ?

[aerobod]

Originally Posted by pikcachu

you would think the new disc would not fit unless you back off the adjusting screw... not the other way around no ?

Typically you have to back off the adjuster to remove the old disc if a rust band has built up on the inner edge of the braking surface where the shoes don’t touch, the rust expands the original surface so will require the shoes to be retracted more than the size of a new disc. The key is to adjust to the correct spec after fitting the new disc.

[pikcachu]

Originally Posted by aerobod

Typically you have to back off the adjuster to remove the old disc if a rust band has built up on the inner edge of the braking surface where the shoes don’t touch, the rust expands the original surface so will require the shoes to be retracted more than the size of a new disc. The key is to adjust to the correct spec after fitting the new disc.

exactly... so basically you are saying he backed it off so much that now the new disc doesn't engage ?

last time i did mine I backed it off a few clicks until the old disc came off and then made sure when i put the new disc that there was just a little bit of resistance when moving the disc by hand and seems to have worked just fine...

[aerobod]

Originally Posted by pikcachu

exactly... so basically you are saying he backed it off so much that now the new disc doesn't engage ?

last time i did mine I backed it off a few clicks until the old disc came off and then made sure when i put the new disc that there was just a little bit of resistance when moving the disc by hand and seems to have worked just fine...

The pawl should be adjusted by 8 or 9 clicks from the shoes touching (depends whether drum diameter in disc is 185 or 160mm diameter), as detailed in the attached procedure.

[Raymondo1234]

I will try and look at it again when I get time.

I appreciate your help.

[Raymondo1234]

So I tried, but even when adjusted to the most closed position, it still isn't enough to get it anywhere near touching.

Is it a different part for xdrive? I can't work it out.

[aerobod]

Originally Posted by Raymondo1234

So I tried, but even when adjusted to the most closed position, it still isn't enough to get it anywhere near touching.

Is it a different part for xdrive? I can't work it out.

There are two different parking brake sizes on these cars that require either a 160mm or 185mm rotor "hat" for the parking brake. You probably need the 160mm hat, but have installed a rotor with the 185mm one. You would need the 345mm x 24mm rotor with the smaller hat for compatibility.

You probably have installed either 34206797607 for plain rotors or 34206797600 for cross drilled rotors (or aftermarket equivalent), but need 34206797605 for plain rotors or 34206797598 for cross drilled rotors. The alternative is to install the larger parking brake assembly off an F30 340i or other vehicle that uses the larger hat. Your original M235xi rear rotors should be the correct 345x24 (34206797605) ones, though.