I put on a new derailleur the other day and noticed some slack in the chain. So, I decided to calculate my chain length with the Park equation. Oops. Mistake. Somehtin' didn't work, and my chain was too short. But when I added the links back, everything went to hell in a bucket (babe, but at least I'm enjoyin' the ride). I must've put soemthing through something wrong, or I don't know what. So, any advice is welcome, or if you just wanna rag on me for being so stupid - be my guest. I can take it.