AZmidget91
Well-known member
- Joined
- Dec 3, 2014
- Messages
- 1,664
So, a while back I did the hidden caliper upgrade using a P34 caliper. Which is a dual 34mm piston caliper. The braking was better, but still required a lot of effort and a solid pedal when it did engage. Doing some research I found the target for the caliper to master cylinder ratio, granted, it's not for rear brakes, but close and gives you a good idea.
http://www.vintagebrake.com/mastercylinder.htm
So, now knowing a little more about brakes, I found what it was stock 9:1... Not good if you want to actually feel the brakes. Now, I getting the ratio for the P34 and stock master cylinder was easy because the master cylinder has the size stamped on it, 1/2". Ok, so now with the P34 and the stock master cylinder it is 14.3:1, better, but still a "wooden" feel. Common rear master cylinder sizes are 11mm, 1/2"(12.7mm), and 13mm. So I made the chart below and added the P32 caliper for those who went with that for their hidden caliper.
Now with that easy chart made up, it's easy to see that the 11mm master cylinder is going to be my best choice. So which one? Well, Brembo of course... So, off to the internet again to find a suitable 11mm master cylinder. Looking around, I found the PS11B, it's 11mm with a side exit for the brake line, which will hide the master cylinder behind the heel guard better. Cool! So, found one on ebay for cheap. Got the master cylinder and immediately noticed my first problem, no threads... Ok, so put helicoils in and now I have threads. Next issue, was my brake line, with the straight fitting, I either hit the belt, or the swing arm. So put on a 45 fitting to angle it forward and up to clear both, only had a chrome one laying around :mad-new: So now got the kinks worked out...well except for the push rod falling out if you accidentally pull up on the pedal, going to add a spring to keep it down, or a stop....
Now, onto the test ride, I can now lock up the brake without putting my body weight on the pedal, just using those calf muscles. Yes, I know..."why would you want to lock up the rear tire" well, to quote a great man, "because I like to party." Many of you will think doing this is a waste, and not needed, but now I have more feel of what's going on with the brake, less effort, and more braking.
Onto the pics!
Comparison of the master cylinders.
Mounted up and showing the 45 fitting on the brake line, will replace that chrome fitting for a black one soon.
With the heel guard you only see the bottom poking out with the Brembo logo
And of course, didn't have the right hose to fit the smaller reservoir up in the stock location.
There are other master cylinders you can use. Some use an integrated reservoir.
After I had done all this research, I then thought, hmm what bike did the P34 caliper come on? Monster 1100... hmm what master cylinder did that come with PS11... So, looks like I decided on the exact brake setup as a Monster. So, that just proves this isn't such a bad idea after all to all you negative Nancys out there.
http://www.vintagebrake.com/mastercylinder.htm
So, now knowing a little more about brakes, I found what it was stock 9:1... Not good if you want to actually feel the brakes. Now, I getting the ratio for the P34 and stock master cylinder was easy because the master cylinder has the size stamped on it, 1/2". Ok, so now with the P34 and the stock master cylinder it is 14.3:1, better, but still a "wooden" feel. Common rear master cylinder sizes are 11mm, 1/2"(12.7mm), and 13mm. So I made the chart below and added the P32 caliper for those who went with that for their hidden caliper.
Now with that easy chart made up, it's easy to see that the 11mm master cylinder is going to be my best choice. So which one? Well, Brembo of course... So, off to the internet again to find a suitable 11mm master cylinder. Looking around, I found the PS11B, it's 11mm with a side exit for the brake line, which will hide the master cylinder behind the heel guard better. Cool! So, found one on ebay for cheap. Got the master cylinder and immediately noticed my first problem, no threads... Ok, so put helicoils in and now I have threads. Next issue, was my brake line, with the straight fitting, I either hit the belt, or the swing arm. So put on a 45 fitting to angle it forward and up to clear both, only had a chrome one laying around :mad-new: So now got the kinks worked out...well except for the push rod falling out if you accidentally pull up on the pedal, going to add a spring to keep it down, or a stop....
Now, onto the test ride, I can now lock up the brake without putting my body weight on the pedal, just using those calf muscles. Yes, I know..."why would you want to lock up the rear tire" well, to quote a great man, "because I like to party." Many of you will think doing this is a waste, and not needed, but now I have more feel of what's going on with the brake, less effort, and more braking.
Onto the pics!
Comparison of the master cylinders.
Mounted up and showing the 45 fitting on the brake line, will replace that chrome fitting for a black one soon.
With the heel guard you only see the bottom poking out with the Brembo logo
And of course, didn't have the right hose to fit the smaller reservoir up in the stock location.
There are other master cylinders you can use. Some use an integrated reservoir.
After I had done all this research, I then thought, hmm what bike did the P34 caliper come on? Monster 1100... hmm what master cylinder did that come with PS11... So, looks like I decided on the exact brake setup as a Monster. So, that just proves this isn't such a bad idea after all to all you negative Nancys out there.
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