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Discussion Starter · #1 ·
Hi all,

I have had new handbrake shoes (mintext) and back pads (brembo) fitted on my 52 E39 yesterday, the brakes work fine and the handbrake does its job on a flat but when parking on a hill this morning the handbrake doesn't work properly. Do they need bedding in and if so do I do that by gently rolling the car and pulling up the handbrake a click or two?

Your help would be much appreciated.

Kind regards,

P_Murtagh2003
 

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Hi all,

I have had new handbrake shoes (mintext) and back pads (brembo) fitted on my 52 E39 yesterday, the brakes work fine and the handbrake does its job on a flat but when parking on a hill this morning the handbrake doesn't work properly. Do they need bedding in and if so do I do that by gently rolling the car and pulling up the handbrake a click or two?

Your help would be much appreciated.

Kind regards,

P_Murtagh2003
Assuming they are adjusted correctly they need to be bedded in. Drive at, say, 20mph for 200 metres or so with the handbrake held up. Don't go around any corners and don't do it in the wet etc. :rofl:
 

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I do not believe bedding of emergency brake shoes is required. I am guessing your emergency brake is not adjusted properly. How high up on the handle do you pull before it engages? If you max out the stroke, you need to take up some of the slack in the cable. The adjustment is at the base of the lever arm. If that is not sufficient, you need to remove your rear wheels and adjust the parking brake shoes within each rotor. Not sure which direction you turn the adjustment wheel to tighten the brake (reducing the clearance between the shoe and the brake drum) but a few turns in either diection will tell you if you are tightening or loosening.
 

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Discussion Starter · #4 ·
Thank you for your posts.
The guy who fitted them said about bedding them in but my misses forgot to tell me that until this morning!

Fudman - On a flat it clicks twice tops 3 times. I have not tried on a hill as the misses had the car and called me saying the handbrake wasnt working on a hill

I hope this helps??
 

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Discussion Starter · #5 ·
I got the misses to roll down the hill but only at a very slow speed and pull the handbrake up until it slightly gripped and then let go. She done this about 4/5 times but it its still not working. Would this have bedded them in or do I need to drive it at 20mph for circa 200m??

Thank you again
 

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The purpose of bedding is to deposit an even layer of brake friction material molecules so that covalent bonds create the friction force of braking at high speeds.

I seriously doubt there is any need (nor any benefit) to bedding the parking brake shoes on our bimmers.

The OP will want to look at the parking brake DIYs in red below for details on how to adjust the parking brake for effectiveness:

- What E39 street use brake pads (1) and rotors (1) and suppliers (1) (2) are most often recommended & how to do a complete four wheel brake job DIY (1) (2) (3) including the parking brake drum shoes (1) (2) (3) & exactly what lube/paste to use and not use (1) & where to lube (1) and not to lube (1) what tools (1) (2) and supplies (1) you'll need & what specifications you must know (1) including minimum specs for the brake shoes (1) (2) taking care to measure torque accurately (1) & how to crack friction material edge codes (1) & how far you can go once the brake wear sensor trips (1) (2) (3) (4) & how long do rotors last (1) & how to clear the check brake lining warning the right way (1) (2) and how to hardwire the sensor (1) (2) & how to diagnose brake-related vibration (1) (2) (3) & the truth about rotor "warp" (1) & how to rebuild the calipers (1) & how to measure runout (1) & should you just turn the rotors (1) & how to remove stuck rusted-on brake rotors (1) & how to remove a stuck 6mm brake rotor set screw (1) & how to replace the anti-rattle spring (1) (2) & what about unsightly rust (1) (2) (3) (4) (5) & how to bed (1) (2) & bleed or flush (0) (1) (2) (3) (4) (5) your brakes & what brake & clutch hydraulic fluid to use (1) and how much it will cost if you do not DIY (1) (2) (3)
 

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And YES, "bedding" is strongly recommended!
Hi Cam,
I was posting at the same time you were so I hadn't seen your post.

Bedding of the pads is a high-speed high-heat affair, whose purpose is to deposit an even layer of friction material on the rotors, specifically to reduce the chance of an uneven layer deposition (and partially to allow for covalent bond making and braking which is apparently a major component of high heat braking friction).

None of that appears to apply (at least in my mind) to the glacially slow speeds where the parking brake operates.

What would the point of 'bedding' a parking brake shoe to the drum be?
 

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...Bedding of the pads is a high-speed high-heat affair, whose purpose is to deposit an even layer of friction material on the rotors, specifically to reduce the chance of an uneven layer deposition (and partially to allow for covalent bond making and braking which is apparently a major component of high heat braking friction).
The "high-speed high-heat affair" is basically "zeckhausen" garbage.
The concept of "purpose is to deposit an even layer of friction material on the rotors" is simply not true. This is basically one-man's (zeckenhausen) claim to fame.
It has never been authenticated by the car guru in the field.

Anyway, this is his garbage for people who are interested:
http://www.zeckhausen.com/bedding_in_brakes.htm

I think "bedding" is recommended and I do it.
But the real rationale behind it is debatable!

The main purpose of "bedding" is to smoothen up both surfaces: the pad's surface and the rotor's surface. Nothing magic about it.
Basically any uneven "microscopic" bits and pieces are "grinded off".

IMHO, this is a better article to read:
http://www.ecstuning.com/stage/edoc/brakebedding.

In simple terms, bedding your brake pads allows the pads to mate with the rotors uneven surfaces. Even brand new brake rotors are covered with microscopic scratches, grooves, and imperfections that must be worn down to create as much surface area as possible for the pads to come in contact with. As your brake pads bed in, they contour to fit every imperfection in the rotors. Below are basic instructions to help bed in your brake pads and rotors correctly.
 

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Thank you for your posts.
The guy who fitted them said about bedding them in but my misses forgot to tell me that until this morning!

Fudman - On a flat it clicks twice tops 3 times. I have not tried on a hill as the misses had the car and called me saying the handbrake wasnt working on a hill

I hope this helps??
The cable length adjustment seems fine but it appears that the shoes are not adjusted properly to the drum. Take it back to whoever installed them and have them readjust the parking brake shoes outward a little bit.

+1 on always setting the car in gear, in addition to the parking brake, when on a hill. Back when I had a manual, I also used to steer towards the curb, just in case.
 

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Discussion Starter · #11 ·
Thank you all for your posts.

Just spoke to the garage and they said they told my misses the drum was pitted. They prob did as the misses fails to tell me these things!!
They have said to try the bedding in and if that doesnt work the drums will need replacing. Does this sound about right
 

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Thank you all for your posts.

Just spoke to the garage and they said they told my misses the drum was pitted. They prob did as the misses fails to tell me these things!!
They have said to try the bedding in and if that doesnt work the drums will need replacing. Does this sound about right
This is why whenever the Parking Brake Shoes are replaced it is always a good idea to either:

1. Resurface the inside of the drum so the Brake shoes have good surface to "bite on to".

or...

2. Install a new REAR rotor (only $40 for Brembo or ATE in the USA). This is the best option!

Your shop cut corner and now you have to deal with it!
 

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I gotta say that something doesn't sound right. If the drum was pitted that badly, they should've called you and told you that you needed a new brake drum (& then charged you for it). But they thought it was good enough to install anyway. Hmmm... :dunno:

Static braking (holding something at rest) is a LOT different from dynamic braking (slowing down from speed). Granted the braking surfaces need to match up and should be free of imperfections and contamination. And unless there was an installation error, they should match up. While pitting of the drum surface can reduce the friction between the brake shoe and the drum surface, it should not significantly reduce the braking power of the emergency brake. If someone put some grease on the shoe or drum, that's a whole 'nother matter.

I would either have them readjust the parking brake (or do it yourself as it will take 20 miutes a side) or just avoid this garage in the future. I smell a rat. :eek:
 

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It's probably worth mentioning that the handbrakes on these cars are not the most effective, from what I've seen and read elsewhere. The cars are relatively heavy, with smallish diameter parking brake drums. I've found that in my car, parking on steeper hills, they do a marginal job.
 

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Discussion Starter · #15 ·
They said they will re-adjust it should the "bedding" in not work. Fingers grossed this works!

Thank you again for all your posts, much appreciated and I will let you know how I get on
 

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The "high-speed high-heat affair" is basically "zeckhausen" garbage.
The concept of "purpose is to deposit an even layer of friction material on the rotors" is simply not true. This is basically one-man's (zeckenhausen) claim to fame.
It has never been authenticated by the car guru in the field.

Anyway, this is his garbage for people who are interested:
http://www.zeckhausen.com/bedding_in_brakes.htm

I think "bedding" is recommended and I do it.
But the real rationale behind it is debatable!

The main purpose of "bedding" is to smoothen up both surfaces: the pad's surface and the rotor's surface. Nothing magic about it.
Basically any uneven "microscopic" bits and pieces are "grinded off".

IMHO, this is a better article to read:
http://www.ecstuning.com/stage/edoc/brakebedding.
in that article he's talkin about bedding PADS AGAINST ROTORS, not SHOES WITHIN THE INNER DRUMS.

and for someone who's DIYs have some made up $hit of drilling holes in thermostats and such, I'd be more hesitant to call Dave's articles garbage :rolleyes:

Stoptech is garbage too? Do they have to be approved by a car guru as well? :rofl:

http://www.stoptech.com/tech_info/wp_bedintheory.shtml
 

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It's probably worth mentioning that the handbrakes on these cars are not the most effective, from what I've seen and read elsewhere. The cars are relatively heavy, with smallish diameter parking brake drums. I've found that in my car, parking on steeper hills, they do a marginal job.
Actually I used to think so (the Parking Brake in E39 was weak) as well when I bought my car in 2006 (when it was 8 years old).
As it turned out, after I replaced the Parking Brake Shoes, it is good like new, it holds the car very well even on a slight hill (but I always use 1st gear and turned the wheels so they hit the curb should the car roll).
 

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Actually I used to think so (the Parking Brake in E39 was weak) as well when I bought my car in 2006 (when it was 8 years old).
As it turned out, after I replaced the Parking Brake Shoes, it is good like new, it holds the car very well even on a slight hill (but I always use 1st gear and turned the wheels so they hit the curb should the car roll).
Right. Mine works okay on a slight hill, but anything steeper (and we have lots of steeper hills here in the Bay Area) presents a challenge, and the car will creep if you don't pull extra hard on the handbrake. This is not the case with the Acura TL and MDX that I've driven. In any event, I've never trusted my car's fate to the handbrake, regardless of make.

I'd be interested to hear what Bluebee and Edjack have to say about their handbrakes, since they've likely parked in similar terrain.
 

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Right. Mine works okay on a slight hill, but anything steeper (and we have lots of steeper hills here in the Bay Area) presents a challenge, and the car will creep if you don't pull extra hard on the handbrake. This is not the case with the Acura TL and MDX that I've driven. In any event, I've never trusted my car's fate to the handbrake, regardless of make.

I'd be interested to hear what Bluebee and Edjack have to say about their handbrakes, since they've likely parked in similar terrain.
If the parking brake is not used regularly, the inner drum will rust. The brake will not hold at that moment.
 

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If the parking brake is not used regularly, the inner drum will rust. The brake will not hold at that moment.
Noted. I always use it; I just make sure the car's in gear and my wheels are curbed as well.
 
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