Ausmini
It is currently Sun Jul 27, 2025 8:31 pm

Board index » Mini Chat » Mini Chat

All times are UTC + 10 hours




Post new topic Reply to topic  Page 1 of 1
  [ 9 posts ] 
  Print view Previous topic | Next topic 
Author Message
willy
 Post subject: Rear wheel cylinders
PostPosted: Sun Sep 18, 2011 11:36 pm 
Offline
1360cc
1360cc

Joined: Mon May 03, 2004 6:46 pm
Posts: 13688
Location: ADL
For a dual circuit system, which rear brake cylinders are the size to go for?

The master cylinder will be this:
"MASTER CYLINDER FOR 1980 ON PRE SERVO (YELLOW IDENTITY TAG)"
http://www.minispares.com/Product.aspx? ... 659&title=

... the rear line will be going through a hydraulic handbrake (with 5/8 master - is this suitable?) and then to the rear wheel cylinders.

Any help appreciated.
Top
 Profile  
 
DA9jeff
 Post subject:
PostPosted: Mon Sep 19, 2011 12:02 am 
Offline
848cc
848cc

Joined: Tue Dec 11, 2007 7:49 pm
Posts: 194
Location: Gawler SA
We have a .70" m/cylinder on our Hydraulic hand brake... thought the rear cylinder should be bigger,not smaller than the front???

...the smaller the cylinder for a given pedal movement equals more line pressure...you want less line pressure on the rear brakes for obvious reasons [or a bias valve.]

_________________
1974 1150cc Leyland Mini S racer,
1975 No motor Leyland Mini "ute"
1991 IPRA Honda Integra (in the build)
1995 Land Rover Discovery 300Tdi

CAMS Scrutineer
Top
 Profile  
 
drmini in aust
 Post subject:
PostPosted: Mon Sep 19, 2011 7:49 am 
Offline
religious status
religious status
User avatar

Joined: Fri Mar 19, 2004 6:19 pm
Posts: 39757
Location: near Baulkham Hills, NSW
DA9jeff wrote:
We have a .70" m/cylinder on our Hydraulic hand brake... thought the rear cylinder should be bigger,not smaller than the front???

...the smaller the cylinder for a given pedal movement equals more line pressure...you want less line pressure on the rear brakes for obvious reasons [or a bias valve.]

This is right for a MC, but the opposite applies for a slave (ie rear wheel) cylinder. You want less area on the piston to get less applied force to the shoes, so fit 5/8" diameter wheel cylinders as used on Cooper S and GT.

Most drum braked cars here had 3/4" rears. They can lock up after you fit front discs (as I found out at 110KMH once in the wet...) :shock:

_________________
DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R. :mrgreen:
Top
 Profile  
 
willy
 Post subject:
PostPosted: Mon Sep 19, 2011 4:45 pm 
Offline
1360cc
1360cc

Joined: Mon May 03, 2004 6:46 pm
Posts: 13688
Location: ADL
Cool so 5/8 if it has disc brakes up front - they are 8.4" if it matters.

And on that note, is the 5/8 MASTER cylinder of the Hydraulic handbrake OK size wise?

8)
Top
 Profile  
 
drmini in aust
 Post subject:
PostPosted: Mon Sep 19, 2011 7:07 pm 
Offline
religious status
religious status
User avatar

Joined: Fri Mar 19, 2004 6:19 pm
Posts: 39757
Location: near Baulkham Hills, NSW
5/8" master cylinders are most uncommon- they were used on 998 Coopers and on nothing else.
Worth $$$ for rarity, if you have one.
I'd fit a 0.7"MC, they are easy to get. :wink:

_________________
DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R. :mrgreen:
Top
 Profile  
 
willy
 Post subject:
PostPosted: Wed Sep 21, 2011 9:11 pm 
Offline
1360cc
1360cc

Joined: Mon May 03, 2004 6:46 pm
Posts: 13688
Location: ADL
I meant the handbrake master, is 5/8".

So 5/8" wheel cylinders for the rears with my 8.4" disc brake setup, yeah?
Top
 Profile  
 
drmini in aust
 Post subject:
PostPosted: Wed Sep 21, 2011 9:47 pm 
Offline
religious status
religious status
User avatar

Joined: Fri Mar 19, 2004 6:19 pm
Posts: 39757
Location: near Baulkham Hills, NSW
Yep, 5/8", unless you like doing emergency loop da loop in the wet on a greasy road at speed... :lol:
Trust me it ain't funny...

_________________
DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R. :mrgreen:
Top
 Profile  
 
willy
 Post subject:
PostPosted: Wed Sep 21, 2011 10:15 pm 
Offline
1360cc
1360cc

Joined: Mon May 03, 2004 6:46 pm
Posts: 13688
Location: ADL
Nope, only handbrake initiated. :lol:
Top
 Profile  
 
poeee
 Post subject:
PostPosted: Thu Sep 22, 2011 12:35 pm 
Offline
1360cc
1360cc
User avatar

Joined: Tue Mar 16, 2004 8:55 am
Posts: 11264
Location: Geelong, Victoria
3/4" is the size of choice for a hydraulic handbrake. A land rover s2 clutch master cylinder.

_________________
Image
Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  Page 1 of 1
  [ 9 posts ] 

Board index » Mini Chat » Mini Chat

All times are UTC + 10 hours


Who is online

Users browsing this forum: No registered users and 92 guests

You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Jump to:  

© 2016 Ausmini. All garage work involves equal measures of enthusiasm, ingenuity and a fair degree of irresponsibility.