RP Rear brake cables

[Roger]

More advice and pictures on this issue here:  http://pub25.bravenet.com/forum/static/s...0&cmd=show

Ruairidh and Ian,

Thanks for the link, a Lot of useful information still on the old forum.
The forward angle of the lever is about 45/50 degrees is this ok?
This does not allow the ball to be nearly in line with the king pin at all, for that it has to be nearer vertical.
My levers are wider than the ones I took off and have a shoulder at the end of the arm this is what seems to be the main cause of the excessive kink in the cable, it does not show where it touches clearly in photo No.3. 
The socket end does not touch the backplate either.

Photo 1
     
photo 2
     
photo 3
   

[Tony Press]

More advice and pictures on this issue here:  http://pub25.bravenet.com/forum/static/s...0&cmd=show

Ruairidh and Ian,

Thanks for the link, a Lot of useful information still on the old forum.
The forward angle of the lever is about 45/50 degrees is this ok?
This does not allow the ball to be nearly in line with the king pin at all, for that it has to be nearer vertical.
My levers are wider than the ones I took off and have a shoulder at the end of the arm this is what seems to be the main cause of the excessive kink in the cable, it does not show where it touches clearly in photo No.3. 
The socket end does not touch the backplate either.

Photo 1
 
photo 2
 
photo 3

The 'new' lever is quite wrong- I would go back to the original levers which look in good order !

[Roger]

More advice and pictures on this issue here:  http://pub25.bravenet.com/forum/static/s...0&cmd=show

Ruairidh and Ian,

Thanks for the link, a Lot of useful information still on the old forum.
The forward angle of the lever is about 45/50 degrees is this ok?
This does not allow the ball to be nearly in line with the king pin at all, for that it has to be nearer vertical.
My levers are wider than the ones I took off and have a shoulder at the end of the arm this is what seems to be the main cause of the excessive kink in the cable, it does not show where it touches clearly in photo No.3. 
The socket end does not touch the backplate either.

Photo 1
 
photo 2
 
photo 3

The 'new' lever is quite wrong- I would go back to the original levers which look in good order !

Tony,
The old lever is badly grooved and the ball oval although it does not show in the photo.
I have spent most of this afternoon with a file and carefully reprofiled the lever, it looks promising.
I hope to have a result sometime tomorrow it is a slow job.
The old one was 0.100” wider at the ball end I have removed the shoulder as well witch is a great improvement.

Roger

[Tony Press]

Tony,
The old lever is badly grooved and the ball oval although it does not show in the photo.
I have spent most of this afternoon with a file and carefully reprofiled the lever, it looks promising.
I hope to have a result sometime tomorrow it is a slow job.
The old one was 0.100” wider at the ball end I have removed the shoulder as well witch is a great improvement.

Roger

Oavality of the ball is not a great worry, but necking is bad. I would look for a good second hand set of levers.

[Roger]

Tony,
The old lever is badly grooved and the ball oval although it does not show in the photo.
I have spent most of this afternoon with a file and carefully reprofiled the lever, it looks promising.
I hope to have a result sometime tomorrow it is a slow job.
The old one was 0.100” wider at the ball end I have removed the shoulder as well witch is a great improvement.

Roger

Oavality of the ball is not a great worry, but necking is bad. I would look for a good second hand set of levers.

Tony,
I have spent today filing the levers to an acceptable profile.    
The result is as below.
On full lock the cable is more or less straight now, just as I expected it to be.
There is still a slight bend showing but that is left over from the previous stress on the cable.
Most of the available levers are identical to mine, I wonder why other people have not had the same problem.
   

Roger

[squeak]

When viewed as in your last photo; if the pendant section of your front lever was given a slight twist so that the ball presents at 90 degrees to the cable (when steering straight ahead) ,you'd eliminate the necking and save yourself a lot of filing. That said removing the 'step' next to the ball has fatigue merit.
This also will bring the endcap a tad further away from the backing plate and the levers are of course left and right handed.
I have seen many so modified and they can't have been from panic stops so is this recommended practice?
 
Others have mentioned the importance of eliminating lost motion from the lever onward, so that the pendant portion can be closer to vertical at rest and then 90 degrees to the cable at full braking.  cheers  Russell

[AustinWood]

Some cable end caps are almost square ended and catch on the backplate. Older ones are rounded.
Twisting the levers does help - if you can do it, they're tough!

[Roger]

Russell,
Thanks for your reply, I like your idea of twisting the lever but do not have any way to achieve this with any consistency so both sides would match. Is it ok to do it cold or is heat required, also would this cause stress in the area that needs it least? I have a collection of well used levers I may practice on first.
I have never liked sharp edges ever since breaking a reground crank that was not done properly.
Your other comment about the ball being under the king pin I agree is a good idea but not sure how to achieve this, twisting the lever would help, but is there a way to reduce the lever angle?
In a drawing I have of the front brake assembly the ball is shown to be biased to one side.
This is a later type of brake than mine.
The cotter pin has a small effect on this angle I believe.
   
Roger

---

Some cable end caps are almost square ended and catch on the backplate. Older ones are rounded.
Twisting the levers does help - if you can do it, they're tough!

I made my own socket and end cap, using a 1/2” ball end drill and radiusing the end to suit.

Roger

---

Russell, 
I have just tried to twist two very old levers using a large adjustable spanner on the lever, it works well cold and does not effect the end where the ball is so no stress on that part.
I wish I had known that one before I did the filing. We live and learn?

Roger

[squeak]

thanks for the feedback Rodger,
 important that the twist is no substitute for any wear in the system including the linings. It is only to achieve 90 degrees where the ball meets the cable when viewed from above. 
When viewed from the side, the pendant lever position is controlled by the cutaway for the cotter and, as you have said, the direction in which it is inserted. The cutaway is handed.
 I would not bend the lever to correct any discrepancies here, rather look at whether the cams are on the correct sides and can you adjust the steepness of the cotter. 
Whilst on the subject of front cotters , I make my own, about 3 inches long and jutting forward, with a light extension spring between the cotter and backing plate. This to help the brake shoe springs counteract the weight of  front cable and fittings.  cheers  Russell

[Roger]

Russell,
I have all ready removed the brake cams and swapped them over, all this achieved is the lever now points the same amount to the rear of the car, not good! (Swapped back again).
Cotter pins are in ok, but may try your idea of spring assist later.
I think I am sorted now just a question of setting the whole system up next.

Roger