Ok, I have a 92 Suzuki Bandit 400. Just recently noticed the bike lurching a small amount at mid range rpm's and some trouble stating and maintaining idle. Thought maby since the bike is stored outside there might have been some water that made its way into the tank. Added dry gas, did nothing, so we pulled a spark plug and it looked like it was running a little lean. It has quad mikuini(appologize if mis-spelled, me no good at english) carbs. Wondering if fuel mixture is something that often or ever comes out of adjustment on carbuorated bikes, and if so how should I go about adjusting? Any tips will rock.