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> Why doesn't my right ebrake work?, It's the asymmetric cables, dummy.
davesprinkle
post Dec 3 2009, 10:14 AM
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Here's why most modern cars have the ebrake handle in the middle of the car -- it's so the cables running to the wheels have identical length and path. How do I know? Here's the anecdote:
For the last year, I've been struggling with my ebrake system. The right caliper just wouldn't clamp as tightly as the left. I've got rebuilt calipers, new pads, new cables, proper clearance, but no worky.

Finally found out why. It's the internal drag of the actuation cables. The passenger-side cable is substantially longer than the driver side. Also, the right-side cable has 3 right-angle bends vs the left-side cable with none. This results in so much internal friction that the cable just binds solid when it's pulled.

I was able to improve the situation somewhat by lubricating the cable. Still not perfect, but much better.
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Chicken
post Dec 4 2009, 11:16 AM
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This is not a design flaw/issue it is an expectation of design- flaw.

And is a quite common one …

only because I can’t get over this one....

The "E-brake" as you call it is not an "E" brake, it is a PARKING Brake, designed to HOLD the car in a standing position.

The design intent with the Equalizer is to distribute equal force to both sides of the car. Left wheel Right wheel ONCE engaged.
It is not designed to work the same a your speed reducing brakes with equal engagement at the same time, as this is not a concern of a Parking brake.

Once the first set of pads make contact with the rotor.. if all is adjusted properly force will then begin to be distributed to the other set that has not made contact yet by using the equalizer bar. Once equalization of force is established additional travel by the hand lever will apply approximately the same value of force to both sides.

Were this gets tricky is if the (equalizer) = cable lengths are too far out of adjustment and an equilibrium between cannot be reached before tension from the main cable is all applied to one side, on our 914s this is usually the Right side wheel that receives little force.

Expecting “first contact” of both sides is not the intent of this design.

If you have improved the timing of contact with lubrication /adjustment, ….fantastic! No harm…
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Cevan
post Dec 4 2009, 01:00 PM
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QUOTE(Chicken @ Dec 4 2009, 12:16 PM) *

The "E-brake" as you call it is not an "E" brake, it is a PARKING Brake, designed to HOLD the car in a standing position.


Maybe in Texas it isn't, but around here, the parking brake is commonly refered to as an "E brake." (IMG:style_emoticons/default/beer.gif)
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SirAndy
post Dec 4 2009, 01:11 PM
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QUOTE(Cevan @ Dec 4 2009, 11:00 AM) *

QUOTE(Chicken @ Dec 4 2009, 12:16 PM) *

The "E-brake" as you call it is not an "E" brake, it is a PARKING Brake, designed to HOLD the car in a standing position.


Maybe in Texas it isn't, but around here, the parking brake is commonly refered to as an "E brake." (IMG:style_emoticons/default/beer.gif)

I presume by the same people that call the fog lights "running lights" and leave them on even when there's not a speckle of fog in a 100 mile radius?

Other people say it so it must be true.
(IMG:style_emoticons/default/rolleyes.gif) Andy
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Posts in this topic
davesprinkle   Why doesn't my right ebrake work?   Dec 3 2009, 10:14 AM
jim_hoyland   I have the same issue.....where did you lube the c...   Dec 3 2009, 10:34 AM
davesprinkle   I have the same issue.....where did you lube the ...   Dec 3 2009, 10:46 AM
tat2dphreak   dunno about OR, or CA, but a hydraulic Parking bra...   Dec 3 2009, 12:02 PM
davesprinkle   dunno about OR, or CA, but a hydraulic Parking br...   Dec 3 2009, 12:56 PM
tat2dphreak   new cables should not bind, perhaps it was bent be...   Dec 3 2009, 01:06 PM
davesprinkle   new cables should not bind, perhaps it was bent b...   Dec 3 2009, 01:27 PM
tat2dphreak   new cables should not bind, perhaps it was bent ...   Dec 3 2009, 01:59 PM
Shade Tree   I've been considering just putting a line lock...   Dec 3 2009, 01:18 PM
JJ914GT   That's exactly why my car has the handbrake in...   Dec 3 2009, 01:45 PM
JJ914GT   The PO installed it before I got the car, so didn...   Dec 3 2009, 04:13 PM
McMark   Dave, did you try adjusting the ebrake cables? An...   Dec 3 2009, 10:37 PM
davesprinkle   Dave, did you try adjusting the ebrake cables? A...   Dec 3 2009, 11:37 PM
PRS914-6   The length of the cable should not effect it. The...   Dec 3 2009, 10:47 PM
davesprinkle   The length of the cable should not effect it. ...   Dec 3 2009, 11:35 PM
PRS914-6   [quote name='PRS914-6' post='1246177' date='...   Dec 3 2009, 11:51 PM
Mike914   My cars both grab the driver's side rotor firs...   Dec 4 2009, 12:11 AM
davesprinkle   My cars both grab the driver's side rotor fir...   Dec 4 2009, 09:07 AM
davesprinkle   Sorry, the friction difference between two new ca...   Dec 4 2009, 09:40 AM
PRS914-6   It cracks me up when people get on a forum and ask...   Dec 4 2009, 10:17 AM
davesprinkle   It cracks me up when people get on a forum and as...   Dec 4 2009, 10:44 AM
Solo914   Dave, First off, Thanks, I know if you were able ...   Dec 4 2009, 11:01 AM
davesprinkle   Dave, First off, Thanks, I know if you were able...   Dec 4 2009, 11:22 AM
Chicken   This is not a design flaw/issue it is an expectat...   Dec 4 2009, 11:16 AM
davesprinkle   This is not a design flaw/issue it is an expecta...   Dec 4 2009, 11:40 AM
Cevan   The "E-brake" as you call it is not an ...   Dec 4 2009, 01:00 PM
SirAndy   The "E-brake" as you call it is not an...   Dec 4 2009, 01:11 PM
messix   Dear Dave, I really don't think that you are...   Dec 4 2009, 11:45 AM
davesprinkle   Dear Dave, I really don't think that you ar...   Dec 4 2009, 12:37 PM
messix   Dear Dave, I really don't think that you a...   Dec 4 2009, 02:58 PM
Chicken   quite simply adjust the cables so the RR makes co...   Dec 4 2009, 11:51 AM
davesprinkle   quite simply adjust the cables so the RR makes c...   Dec 4 2009, 12:26 PM
SirAndy   I call the system an "emergency brake...   Dec 4 2009, 12:45 PM
davesprinkle   I call the system an "emergency brake...   Dec 4 2009, 12:56 PM
SirAndy   Its other function is as an EMERGENCY brake. Firs...   Dec 4 2009, 01:18 PM
davesprinkle   I stomp on the brakes, *POP* it said and the peda...   Dec 4 2009, 01:33 PM
SirAndy   [quote name='SirAndy' post='1246418' date='Dec 4 2...   Dec 4 2009, 01:37 PM
davesprinkle   Did you also read my question? I'll ask again...   Dec 4 2009, 03:09 PM
Solo914   [quote name='SirAndy' post='1246428' date='Dec 4 ...   Dec 4 2009, 03:18 PM
SirAndy   From the owners manual:   Dec 4 2009, 12:53 PM
tat2dphreak   that happened to me on an old hunting truck we had...   Dec 4 2009, 01:56 PM
Chicken   guys i am glad we can all give each other a hard t...   Dec 4 2009, 02:50 PM
SirAndy   A+ for your lubrication skills :thumbsup: D- for ...   Dec 4 2009, 03:13 PM
Shade Tree   Don't the brake lines travel through the tunne...   Dec 4 2009, 03:17 PM
messix   Don't the brake lines travel through the tunn...   Dec 4 2009, 03:22 PM
SirAndy   :lol4: http://wtanaka.com/node/7745   Dec 4 2009, 03:38 PM
MDG   :lol4: http://wtanaka.com/node/7745 :rotfl: ...   Dec 4 2009, 08:14 PM


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