My K8 600 did the same thing this summer right around the time I hit 5,000 miles on the odometer. After reading numerous forums I found a Service Bulletin from Suzuki stating the problem and the solution. . . it's the O2 sensor and it is covered under a 4 year warranty as long as you have under like 18,000 miles. I went to my dealer and at first they tried to say that it wasn't listed on their system, but after I bitched them out, they decided to look into it further. It took a week, but they got the sensor and replaced it free of charge! I've put over 2,000 miles on my bike since then and the problem has not returned!!!! : ) If you're having this problem, stop reading the forums and go to your dealer and get the O2 sensor replaced. You won't regret it!!!