81 seca 750. When I got the bike, the odometer was stuck on 1999.7 and the speedo jumped around. It was accurate at some speeds, but not others. Kind of like a clock without a battery - right 2x's a day. The tripometer worked, though the knob broke, I could turn it with a fishing pliers. Now the tripometer and speedo don't work at all. Fortunately, the tach is good and I have figured out my speed using this. Buddy of mine suggests getting new speedo cable should solve the problem. I just don't want to lose the tach. Thoughts??