1955 Road Rocket clutch parts

[fenderman!]

I have a 1955 BSA Road Rocket...The clutch chainwheel has cork inserts..I've noticed that there are inserts that 1/8 inch thick and 3/8 inch inserts made of a harder compound.When I purchased a new chainwheel it came with the harder inserts..What is the difference and does it matter?

[bikerbob]

I would suspect that you have the original 6 spring clutch fitted as it had he chainwheel with cork inserts. I have 6 spring cltch fitted to my 1956 S/A A7 and when I overhauled it about 5 years ago I fiited a new chainwheel with the harder inserts and it has worked OK now for 5 years originally those inserts were made fro m cork also the friction plates from that time had cork inserts  but the new plates today have bonded material fitted.