I just opened up my starter access cover to find the starter was turning all the time even with motor running. I never heard one spin so fast. I removed the chain and small sprocket - will pull the hub and large sprocket to see what´s up. Will let you know the find. May be able to help you understand yours. I had a 79 kz750 twin 25 years ago that did the same thing yours is doing. good thing for kick starters.