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Discussion Starter #1
Could someone please describe how the servo-assist brakes work (or point me to a post - I can't imagine it hasn't been covered by now) ? Specifically, what kind of servo is it and how does it increase hydraulic pressure in conjunction with what's input by the brake lever? Is it a pump? i linear actuator on a piston? How it works will go a long way to understand its reliability and longevity. Also, if the new system is not servo assisted, then either force on the lever has to increase or braking force has to decrease. The constant in this equation is lever throw distance - the extra force from the servo has to come from somewhere to provide the same brake force/lever force. Why? I'm still struggling with the '06 or '07 question... :confused:
 

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Brakes

The levers are the control circuit for electric pumps that multipy the force at the calipers, AND are the answer to the question no one asked. Mine work fine, but so do the brakes on every other bike I ride, none with all that monkey motion.
H



Kalmarjaeger said:
Could someone please describe how the servo-assist brakes work (or point me to a post - I can't imagine it hasn't been covered by now) ? Specifically, what kind of servo is it and how does it increase hydraulic pressure in conjunction with what's input by the brake lever? Is it a pump? i linear actuator on a piston? How it works will go a long way to understand its reliability and longevity. Also, if the new system is not servo assisted, then either force on the lever has to increase or braking force has to decrease. The constant in this equation is lever throw distance - the extra force from the servo has to come from somewhere to provide the same brake force/lever force. Why? I'm still struggling with the '06 or '07 question... :confused:
 

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Servo

I believe the servo assist is there primarily for the ABS to function. As the ABS cycles from release to apply the servo helps re-apply the pressure.
 

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Kalmarjaeger said:
Could someone please describe how the servo-assist brakes work (or point me to a post - I can't imagine it hasn't been covered by now) ? Specifically, what kind of servo is it and how does it increase hydraulic pressure in conjunction with what's input by the brake lever? Is it a pump? i linear actuator on a piston? How it works will go a long way to understand its reliability and longevity. Also, if the new system is not servo assisted, then either force on the lever has to increase or braking force has to decrease. The constant in this equation is lever throw distance - the extra force from the servo has to come from somewhere to provide the same brake force/lever force. Why? I'm still struggling with the '06 or '07 question... :confused:
I thought I still had a file showing the mechanics of the system, but can't find it. Too bad because I remember how well it explained the system.

But here's a "hand waving" attempt. Pressure from the lever/master cylinder directly pressurizes the wheel circuits and, as it does, this pressure causes a valve to open which allows pressurized fluid from the servo pump to join in and greatly amplify the hydraulic pressure generated by your hand squeezing the lever connected to the master cylinder. The more pressure from the lever, the more the valve is opened and this lets in more pressure from the booster pump circuit into wheel circuits. Whenever the hand lever is moved jsut a little, the hydraulic booster pump is turned and full pressure in made in that circuit. But the amout of hydraulic pressure from the booster pump that goes to the wheel circuit is controlled by the valve I cannot explain without the drawing. If you squeeze the lever real hard, then the booster circuit gets opened more and the pump has to work harder to keep the booster circuit pressure up. You can hear that since the pump sound changes as you squeeze the lever harder. When you are stopped, I mean.

How the linking works and how the balance between front and back is optimized - that's voodoo to me.

I know this isn't so helpful, but without the drawings, I can't explain (or fully remember either).
 
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