Secondary master cylinder linkage orientation

Joined
Nov 19, 2024
Messages
11
Age
69
Location
U.K. Oxfordshire
Bike
ST1100 ABS/TCS
Can anyone on here please confirm that I've got the secondary master cylinder linkage fitted correctly. It does not seem to operate the cylinder properly when
push the left calliper upwards (as it would move when applying the front brake with the bike moving).
All the pivots are free and lubricated.
 

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It does take some pressure to compress the SMC. Does pressing hard on it apply the rear brake?

If you shake it vigorously back and forth in that same direction, i.e., towards and away from the fork tube, does it rattle, i.e., some free play? If so, suspect a stuck SMC.
 
I thought the st1100 didn't have a SMC. I know there is an anti dive valve connected to the caliper bracket on some models. What he is pointing to looks like some ABS valves. Avatar states 1100 abs,tcs.
Yeah, confusing, but 3 piston caliper & SMC is definitely a '96 onward ABS-II/CBS...
 
Can anyone on here please confirm that I've got the secondary master cylinder linkage fitted correctly. It does not seem to operate the cylinder properly when
push the left calliper upwards (as it would move when applying the front brake with the bike moving).
All the pivots are free and lubricated.
I thought the st1100 didn't have a SMC. I know there is an anti dive valve connected to the caliper bracket on some models. What he is pointing to looks like some ABS valves. Avatar states 1100 abs,tcs. The more I think about it he is playing with the anti dive valve and pointing to a brake valve.
 
I thought the st1100 didn't have a SMC. I know there is an anti dive valve connected to the caliper bracket on some models. What he is pointing to looks like some ABS valves. Avatar states 1100 abs,tcs. The more I think about it he is playing with the anti dive valve and pointing to a brake valve.
No - I'm pointing to the secondary master cylinder on the left fork leg. Nothing to do with anti dive.
 
No - I'm pointing to the secondary master cylinder on the left fork leg. Nothing to do with anti dive.
Ok , good . Are there wires that go to the SMC? What year are we working with , that important to know. And just pushing it should not apply brakes to the best of my limited knowledge of that system.
 
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But it should not create pressure just distribute it ??
I don't understand the question.

When the front wheel is rotating and the front brake applied, while the right caliper does not move, the left caliper bracket allows the caliper to move toward the fork tube.

The piston of the SMC is affixed to the fork tube, so when the left caliper moves toward the fork tube, the SMC housing is pushed over the piston, applying some rear brake.

Whether you push the piston into the cylinder, or push the cylinder over the piston, the relative motion applies force to the fluid, in turn applying braking force at the calipers.
 
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