Re: I\'m guessing this is bad?
Don't worry, that's absolutely normal. Suzuki spot-hardens the Birfield, so that where the bearings un the steel is hard for good anti-wear characteristics, but the rest of it stays relatively soft so that it's less prone to shatter. Every single Birfield joint has that discoloration.
When you clean out the joints, they almost always get stiff. Make sure you pack it VERY well with some good grease. I use marine grease in mine. It will take a long time to completely pack the joint. Don't get lazy....pack a ton of it deep into the joint, and it'll loosen right up and you'll be good to go.
-- Geoff Beasley