Rear Brake Cylinder Movement

Discuss mechanical problems here.
Forum rules
By using this site, you agree to our rules. Please see: Terms of Use
Post Reply
Packedup
Minor Legend
Posts: 1429
Joined: Tue Aug 02, 2005 1:40 am
MMOC Member: No

Rear Brake Cylinder Movement

Post by Packedup »

Managed to get a set of rear shoes this morning, and have just finished fitting them.

The old shoes were very unevenly worn - The upper halves had a fair bit of life left, the lowers were almost on the metal.

I noticed when fitting the new ones that the slave cylinders seem a little sloppy, and foul rather than slide fully. This would explain the wear pattern (only one shoe is being pressed into contact with the drum), but what explains the sloppy cylinders? I take it they're held on with circlips/ horseshoe clips? Is it possible for the clips to weaken with age, or is it more likely they're just missing?
crossword
Minor Fan
Posts: 119
Joined: Tue Nov 22, 2005 12:29 pm
Location: Sheffield
MMOC Member: Yes

Post by crossword »

Your ' uneven' wear is normal . The rear brakes have one leading & one trailing shoe per side , the leading shoe is effective when braked are applied & you are moving forwards . Trailing shoe is effective when you brake whilst moving backwards . The front brakes have two leading shoes per side & only brake properly when moving forwards . If ALL the brakes had leading shoes , you would have little braking effort whilst moving backwards . The sliding wheel cylinder is to compensate for the uneven wear.
Packedup
Minor Legend
Posts: 1429
Joined: Tue Aug 02, 2005 1:40 am
MMOC Member: No

Post by Packedup »

Surely though the rear cylinder slides enough to press both shoes into the drum (though only one leading edge)? My cylinders don't appear to be doing all that much sliding, more wobbling! With the shoes off the cylinders only slide up properly if pressed against the backplate - Leave them to sit how they want and there's not much movement before they foul. I'm not entirely convinced this is very useful...
bigginger
Minor Maniac
Posts: 5928
Joined: Thu Sep 09, 2004 11:01 pm
MMOC Member: No

Post by bigginger »

They do move in and out a lot with no drum on - fitting/refitting the beehive springs to the backplate would cure that, I guess
Packedup
Minor Legend
Posts: 1429
Joined: Tue Aug 02, 2005 1:40 am
MMOC Member: No

Post by Packedup »

bigginger wrote:[...]the beehive springs to the backplate would cure that, I guess
Those would be the things I just saw on the ESM site, but didn't see on the Minor this morning then..?

"Double bother"
bigginger
Minor Maniac
Posts: 5928
Joined: Thu Sep 09, 2004 11:01 pm
MMOC Member: No

Post by bigginger »

Lots of people leave them off - not absolutely vital bits. Try them with the drum on, as it holds things more firmly. As usual from me, that's not a textbook answer, and it's all at your own risk :D It's true though - it's pretty rare IME to see them fitted
Willie
Minor Legend
Posts: 3204
Joined: Tue Feb 12, 2002 12:00 am
Location: S E London
MMOC Member: No

rear shoes

Post by Willie »

Just remember that the rear shoes are Supposed to slide up and down,
unfortunately this means that they can drop down when not in use until the lower shoe rubs on the drum!
Willie
[img]http://i39.photobucket.com/albums/e197/wuzerk/mo9.jpg[/img]
Packedup
Minor Legend
Posts: 1429
Joined: Tue Aug 02, 2005 1:40 am
MMOC Member: No

Re: rear shoes

Post by Packedup »

Willie wrote:Just remember that the rear shoes are Supposed to slide up and down,
Down isn't the problem, it seemed up was more tricky due to the catching on the backplate. Hard to tell if that's still a problem with everything fitted now of course!
unfortunately this means that they can drop down when not in use until the lower shoe rubs on the drum!
That makes sense (in terms of what happens, not design!). Here's hoping if it does happen it takes a long time so I don't have to get covered in old brake grime again for a while..
bmcecosse
Minor Maniac
Posts: 46561
Joined: Wed Feb 16, 2005 11:24 pm
Location: ML9
MMOC Member: No

Post by bmcecosse »

Presumably the handbrake cable is supposed to steady them enough that they don't 'fall down' to any great degree.
ImageImage
Image
Post Reply