Read many prior posts. Bought a used 650 with excessive whine, especially on acceleration. Quietens down at level speed. Local dealer serviced and changed all fluids, transmission, etc. Noise no better. Bike only has 4,400 miles. The dealer said to rebuild transmission would be $3,300. Is it safe to ride with the noise. The bike is perfect otherwise. Any possibility of it locking down? Do not know what else to try, sure do hate to put $3,300 more into a $4,800 bike. Thanks