Author Topic: Front brake mc size  (Read 627 times)

Online John A

  • Gaggle Hero
  • *****
  • *
  • *
  • *
  • *
  • Posts: 4907
  • No way to slow down...
  • Location: Hager city ,western WI
Front brake mc size
« on: May 08, 2021, 07:35:26 PM »
 I’m going to put on another disc on Deb’s 02Stone because I’ve now gotten all the parts I need.  What size master cylinder do I use for a double disc non linked system?  I have that info at the shop and I’ll read over it but what experiences did you have with it?
John
MGNOC L-471
It is easier to fool people than it is to convince them that they have been fooled-Mark Twain
99 Bassa, sidecar
02 Stone
84 V65C
15 F3S Spyder

Online RinkRat II

  • Gaggle Hero
  • *****
  • *
  • *
  • *
  • *
  • Posts: 2188
  • Lake Powell AZ
Re: Front brake mc size
« Reply #1 on: May 08, 2021, 11:38:21 PM »

 Here's  some good info for what your doing.  Fun With Numbers!
     http://ducatimeccanica.com/brake_ratios.html

      Good Luck
     Paul B :boozing:
A Miller in the hand is worth two in the fridge.

Online moto

  • Gaggle Mentor
  • ****
  • *
  • *
  • Posts: 771
  • Potrebbe andare peggio, potrebbe piovere!
  • Location: Madison, WI
Re: Front brake mc size
« Reply #2 on: May 09, 2021, 01:24:47 PM »
Another good source is Guzziology. You'll need to know the sizes of both your master and slave cylinders to get started.
850 T-3
Griso 1100 corretto
2023 Royal Enfield Classic 350
Italjet Buccaneer 250 (ex-SSR) -- now sold
credit for 2500+ postings lost in the database meltdown of Feb 9, 2020

Online John Croucher

  • Gaggle Mentor
  • ****
  • Posts: 647
Re: Front brake mc size
« Reply #3 on: May 09, 2021, 02:02:48 PM »
Here are a couple of pictures on brake line routing I used to clean up appearance.
Bike originally had linked brakes. 
The right size m.c. will give you two finger braking.  To small and you will have a soft lever, to big and the lever will be hard with little braking.  Just guessing, I think I used a 14mm. on the front by Brembo.





Wildguzzi.com

Re: Front brake mc size
« Reply #3 on: May 09, 2021, 02:02:48 PM »

Offline moto-uno

  • Gaggle Hero
  • *****
  • *
  • Posts: 1397
  • Location: Burnaby , B.C
Re: Front brake mc size
« Reply #4 on: May 09, 2021, 03:19:22 PM »
  I might suggest you simply try it with what you have ( it may be fine , different , but fine) !   Peter

Online Turin

  • Gaggle Hero
  • *****
  • *
  • *
  • *
  • *
  • Posts: 5146
    • crap and stuff
  • Location: Chandler, Arizona
Re: Front brake mc size
« Reply #5 on: May 09, 2021, 11:45:48 PM »
I like 14mm. 15mm also alright.
1997 Daytona RS
1991 Rennsport California III
1991 LeMans 1000
1987 LeMans SE Dave's Cycle Racer
1984 LeMans III
1985 Sidlow Guzzi
1974 850-T Sport
1969 A-series Ambassador
1996 Triumph Daytona 1200
1996 Triumph Daytona 900
1982 Alfa Romeo GTV6 Balocco SE 3.0

Online skippy

  • Gaggle Mentor
  • ****
  • Posts: 729
Re: Front brake mc size
« Reply #6 on: May 10, 2021, 08:21:44 AM »
I found that when I converted my 03 Stone to a twin disc setup the 17mm master cylinder I sourced from an Apillia was just about perfect. Two finger operation would provide really good feel and feed back as well as haul the bike to a full stop with little effort.

Skippy 
23 V100 Mandello
20 V85TT

Online John A

  • Gaggle Hero
  • *****
  • *
  • *
  • *
  • *
  • Posts: 4907
  • No way to slow down...
  • Location: Hager city ,western WI
Re: Front brake mc size
« Reply #7 on: May 10, 2021, 11:33:59 AM »
When I get the bike and measure what  master came on it with the original single disc I can get an idea of how it’ll work for two discs by the charts. Thanks for the replies
John
MGNOC L-471
It is easier to fool people than it is to convince them that they have been fooled-Mark Twain
99 Bassa, sidecar
02 Stone
84 V65C
15 F3S Spyder

Online Antietam Classic Cycle

  • Gaggle Hero
  • *****
  • *
  • Posts: 14141
  • Happily stuck in the past.
    • Antietam Classic Cycle
  • Location: Rohrersville, Maryland
Re: Front brake mc size
« Reply #8 on: May 10, 2021, 12:12:34 PM »
When I get the bike and measure what  master came on it with the original single disc I can get an idea of how it’ll work for two discs by the charts. Thanks for the replies

It should have a PS13 front master cylinder. The calipers are P4 30/34. Using an average of 32 mm for the 4 pistons, you'd end up with a 24.2 to 1 ratio. Just for reference, the V11 Sport used a PS16 with a pair of the same calipers.
Charlie

Offline Tusayan

  • Gaggle Hero
  • *****
  • Posts: 1788
Re: Front brake mc size
« Reply #9 on: May 10, 2021, 01:50:25 PM »
Just for reference, the V11 Sport used a PS16 with a pair of the same calipers.

Which is equivalent to 5/8 inch, the typical master cylinder size used by almost everybody with those calipers.
« Last Edit: May 10, 2021, 01:51:49 PM by Tusayan »

 

Quad Lock - The best GPS / phone mount system for your motorcycles, no damage to your cameras!!
Get a Wildguzzi discount of 10% off your order!
http://quadlock.refr.cc/luapmckeever
Advertise Here