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Discussion Starter · #1 ·
What’s up guys. Managed to get the DCBS working after 1 million bleeds.

I’m now looking at a strange issue where upon depressing the rear pedal, it gets about halfway, then stops, judders all the way down to the end of its travel.

never encountered this on any other bike.

it takes an enormous amount of pressure for me to bottom out the pedal. Any ideas on what this could be? My rear brakes are free and I can spin the wheel, I seem to have functioning brakes.

fronts drag slightly but I am thinking that’s more of an EBC HH+backing plate thickness issue than anything else…?

all replies appreciated.
 

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Basically it seems you dont understand the way of operation of the dual cbs . you are not alone about 90 pct do not .or dont want to understand it
Some time ago i wrote about this and more recently a 3 part series on several fb forums as well
Google cbr dual cbs schematic . That will already provide you with some basic detail
It seems as if you want to force the pedal stroke all the way down
Why?
Whats the point?
The juddering you feel is normal its the pressure balancing valve under the seat relieving overpressure to the rear caliper
Its a primitive abs system that works very well as long as maintained correctly
 

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Discussion Starter · #3 ·
Basically it seems you dont understand the way of operation of the dual cbs . you are not alone about 90 pct do not .or dont want to understand it
Some time ago i wrote about this and more recently a 3 part series on several fb forums as well
Google cbr dual cbs schematic . That will already provide you with some basic detail
It seems as if you want to force the pedal stroke all the way down
Why?
Whats the point?
The juddering you feel is normal its the pressure balancing valve under the seat relieving overpressure to the rear caliper
Its a primitive abs system that works very well as long as maintained correctly
Hi, thanks for your reply. Contrary to your opinion, I do understand how the system operates, having read the service manual and nearly every piece of literature written here, including your own struggles with the system and also rebuilding the entire system and struggling through troubleshooting.

Simply asking for any advice RE what I believed to be an incorrect operation of the pedal - as you say - it’s a proto-ABS system and I’d rather have some more experienced views on whether it seems to be working or not before I take the bike out into the road - given my unfamiliarity with the quirks of the system itself past the actual architecture of the dual combined circuits.

cheers for the info. If that is normal operation - it sure doesn’t feel like it!
 

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What’s up guys. Managed to get the DCBS working after 1 million bleeds.

all replies appreciated.
So the lever goes firm, then from that point, judders to the end of the brake peddle travel? like a warped rear disc kind of pulsating or a sticky/binding kind of lever judder or your locking up the rear tyre and the tyre is hopping and the chain is slapping the swing arm kind of judder?
 

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Discussion Starter · #5 ·
So the lever goes firm, then from that point, judders to the end of the brake peddle travel? like a warped rear disc kind of pulsating or a sticky/binding kind of lever judder or your locking up the rear tyre and the tyre is hopping and the chain is slapping the swing arm kind of judder?
Neither of those - I haven’t moved the bike from its garaged position yet. Few walking tests - the rear stops as I intend. Rear disk not warped as far as I can tell. Rear wheel is free when no braking force applied. Pedal is clean and free, cleaned up every part of it, the footpeg assy, greased and dismantled rear MC + cleaned that.
 

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Hi, thanks for your reply. Contrary to your opinion, I do understand how the system operates, having read the service manual and nearly every piece of literature written here, including your own struggles with the system and also rebuilding the entire system and struggling through troubleshooting.

Simply asking for any advice RE what I believed to be an incorrect operation of the pedal - as you say - it’s a proto-ABS system and I’d rather have some more experienced views on whether it seems to be working or not before I take the bike out into the road - given my unfamiliarity with the quirks of the system itself past the actual architecture of the dual combined circuits.

cheers for the info. If that is normal operation - it sure doesn’t feel like it!
Basically if you use the pedal only and all is tickety boo the pedal should descend 10 mm then become firm
The bike should brake evenly between front and back with minimal dive
If you load the pedal above the setting of the rear relief valve the plunger will ocillate to relieve the pressure to the rear wheel
This will vary depending on the torque load given by the front left caliper in the secondary
You may also hear a pop or squeaky nose from the front right delay valve as this operates
Cheers
Paul
 

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Discussion Starter · #7 ·
Basically if you use the pedal only and all is tickety boo the pedal should descend 10 mm then become firm

The bike should brake evenly between front and back with minimal dive

If you load the pedal above the setting of the rear relief valve the plunger will ocillate to relieve the pressure to the rear wheel
This will vary depending on the torque load given by the front left caliper in the secondary
You may also hear a pop or squeaky nose from the front right delay valve as this operates
Cheers
Paul
1. Yes I’ve got that
2. I think that’s the case.
3. I do have the dreaded squeak, yeah

so all in all I should be good.Amusingly enough, between posting my question and testing again yesterday,the judder stopped. Cracked the banjo on the PCV as I suspected air in there, then bleed twice more and now feels good.

thanks for the advice.
 

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1. Yes I’ve got that
2. I think that’s the case.
3. I do have the dreaded squeak, yeah

so all in all I should be good.Amusingly enough, between posting my question and testing again yesterday,the judder stopped. Cracked the banjo on the PCV as I suspected air in there, then bleed twice more and now feels good.

thanks for the advice.
Welcome
The bleeding process is ... unusual and described in my articles
 

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Sorry to interrupt, but can we get the links to those threads? Can't seem to find them in Resource Center.
 

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They would be in the service manual. You'll have to download it the look up the braking section.
 
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