One thing that will quiet them is valvoline bike oil. Forgot the exact name, but it's available at autozone. I read that it quiets the engine here at this forum in fact. Tried it and sure enough it did quiet it down. Valve tapping was probably 1/2 as loud at startup. But to be honest i'm not sure if it was much quieter once warm, but definatly quieter when started and for the first few miles anyway. the reason i can't say for sure if it's quiet after it warms up is because i thought i noticed it getting louder as it warmed up. But i wasn't sure because i was too busy noticing how much slower the bike accellerated ! Yes, it made a considerable difference in that regard which prompted me to dump this new oil and go back to Mobil Vtwin immediatly. I guess it's the lack of slickness, as this stuff is dino oil. In any case the Vtwin oil makes the bike run very noticably quicker, the valvoline makes it run quieter. if you're willing to make that trade i'd say is a lot quieter when cold and possibly a bit quieter when warm. But when warmed up for say 20 miles it may be as noisy at that point. I just can't say. STP might help too, tho i don't know if that stuff is good for the bike.
