Author Topic: Front brake mc size  (Read 258 times)

Online John A

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Front brake mc size
« on: May 08, 2021, 07:35:26 PM »
 Iím going to put on another disc on Debís 02Stone because Iíve 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 Iíll read over it but what experiences did you have with it?
John
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Offline RinkRat II

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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:
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Online moto

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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.
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Offline John Croucher

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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.





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

Online moto-uno

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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

Offline Turin

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Re: Front brake mc size
« Reply #5 on: May 09, 2021, 11:45:48 PM »
I like 14mm. 15mm also alright.
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Offline skippy

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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 
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Online John A

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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 itíll work for two discs by the charts. Thanks for the replies
John
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Offline Antietam Classic Cycle

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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 itíll 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
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Offline Tusayan

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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 »

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