suspension by applying a "rubber renewal" product to the rubber bushing? I've considered doing this to my Shinon Red Boron but have been nervous about potential damage if renew liquid migrates up the cantilever. This is an older cartridge and the suspension appears to be holding up but I'm looking at this as possible preventative maintenance.
In the past I've had good luck on belts for turntables and tape decks with a product called Rubber Cleaner Revitalizer by PRB Line.
I really enjoy the Shinon and it still tracks without distortion on highly modulated passages in spite of its age. Therefore I'd like to keep it going as long as possible. I've always had two or three cartridges so the Shinon has had only intermittent use since new and does not have nearly a thousand hours.
Thanks if you can share any experience or recommendations.