My bike seems to be developing a shifting problem. I've searched, but most of the similar problems have been happening to new bikes and getting better as time goes on. Some suggest that lowering your shifter may help, but this is a new problem for me and it's getting worse. Yesterday I had tons of missed shifts between 1st and 2nd; hitting neutral and having a real hard time getting into 2nd. After 2nd, up shifts aren't a problem. I've got about 1500-2000 miles on my bike and have been using Rotella T for most of that time. I change the oil every ride, so it was definitely fresh. Any help is greatly appreciated.