Hard to tell what is happening with your tires. I bought Specialized Pros last year and am still riding them. Tires last forever for me as i am only 125 pounds but I have seen s bulges in tires. Usually if it is premature, i.e. not too many miles on them, I really think it is a manufacturing defect. But, if you rode them 6 months, time to anty up for new tire. In any event, if there is an s bulge by all means replace the tire - it is not worth crashing!