(1994 R1100RS) I have had this bike for 1 1/2 years now and I'm noticing lately that the power on acceleration in the 4500+ rpm range drops off abruptly. Does this indicate that the valves need resetting? It has 41,000 miles and I haven't done the valves for at least the 15,000 miles I've had the bike. It runs beautifully at lower rpm's.