CB77 air filter tubes soft?

[Warren Goodman]

Back in the days before Armor All brake fluid was the tire black rubber softener of choice. Mine are quite hard now so I will try some silicone based fluid and report.

[brewsky]

Wintergreen oil.
I used this method on an old Yamaha dirt bike boot and it did work. Don"t know how long it lasts though.
Put 3oz in a small pan of water and simmer for a couple hours. Set the boots on something in the pan to keep them from direct contact with the bottom of the pan.
I've also used a hair dryer to heat the boots, then sprayed with silicone just before installation.
I would try that first.
http://forums.sohc4.net/index.php?topic=62328.0