CBS is Combined braking system;
AFAIK it is a Honda thingie.
You will void the warranty on the Yam bikes if you don't get it serviced by Yam/Dealer. That is what the Mumbai Yam shop told me. I have a 40 km ride up to their showroom for my service due any time now. I'm planning to truck the damn beast there and back; don't want to ride to malad all the way from south mumbai.
Cheers,
Streetfighter