Brembo brake proportioning valve
Moto Guzzi V7 Sport, 750 S, 750 S3, 850 T, 850 T3, 850 T3 California, V1000 I-Convert, V1000 G5, 1000 SP, Le Mans, Le Mans II, Le Mans CX 100, Le Mans 1000, 1000 SP III, 1000 S, California II, California III, California 1100, California Jackal, California EV, California EV Touring, California Aluminium, California Titanium, California Special, California Special Sport, California Stone-Metal, California Stone-Touring, California Classic, California Touring, and California Vintage models
Thanks to Charles Cooper for sending me this information via email. In Charles' own words:
I came across an article relating to the connections for this valve but for the life of me can't find it again. The valve is the one with a round rubber boot approximately 32 mm diameter covering the end with spring piston circlip. The valve has a mounting flange with two 6 mm bolt holes 35 mm apart and is fixed on the left hand side behind the side panel. It has 5 ports: master cylinder, front caliper, rear caliper, brake switch, and 6 mm bleed nipple. I have recently overhauled my Le Mans 1000 braking system and replaced such a valve. I reckon it had been incorrectly fitted as at MOT the brakes were appalling. It was originally fitted as per the article advice with I reckon the master cylinder and front left hand caliper the wrong way round. I have checked several parts books and translated front, rear, master, cylinder from Italian and conclude this is the correct arrangement for the connections:
- F-ANT= Front left hand brake caliper
- MC-PO= Master cylinder connected to rear master brake cylinder
In Italian,master cylinderismaster cilindroandrearisposteriore.
- STOP= Brake switch
- POST-R= Rear brake caliper
The article has the front left hand brake caliper onMC-POand the master cylinder onF-ANT. If you look at the valve theMC-POconnection is completely different from theF-ANTandPOST-Rbrake connections, which are identical. The master cylinder connectionMC-POhas a separate screw-in plug with a nylon diaphragm / filter and O-ring arrangement, which also makes sense.