Paoli fork dampers
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 Charlie Mullendore of Antietam Classic Cycle for sending me this information in a private e-mail. In Charlie's own words:
I'm installing new FAC dampers in a customer's Le Mans III and the original Paoli(?) cartridge leaked like a sieve, so I did a little dissection. The top cap with air fittings just screws out, under that is a rubber bladder with a ball-shaped tip.
When air pressure is added to the bladder, the tip restricts flow through the orifices.
More pressure = stiffer damping. At least that's the theory - in reality most of these leaked off pressure quickly and because of the small volume were very hard to pressurize accurately anyway.
Once the cap is off and the bladder removed, all of the oil can be drained from the cartridge and oil of a different viscosity put back in. That is, if the cartridge doesn't leak...