Posted by Tim Schroeder on July 23, 2001 at 20:42:08:
In Reply to: What's causing this noise??? posted by Scout on July 23, 2001 at 18:28:19:
It might help to know where the noise originates. Does it seem to come from the upper engine area, as in cylinder, cylinder head or head cover (valve area)? Or does it seem to come from the lower engine area, such as the transmission or crankcase?
Does the noise change, appear or disappear depending upon speed and gear selection, or riding versus idling, etc.?
Does the noise get louder or a lot worse while the engine gets hot?
Hogryder's suggestion is good, change the oil and filter and see if that helps. If not, you might need a valve or other adjustment. Have you ever adjusted the valves, or decompression cable, since owning the bike? (FYI, when changing your oil, DO NOT OVER FILL. The manual says 2.4 quarts with filter change, but in reality it's less to get the level to the full-notch on the sight window. Put in two quarts, then run it for a minute or two. let it sit, then check the level. If you over-fill, you'll get back pressure through the airbox and the engine might want to sputter and hesitate, or not run at all. Hard to diagnose other problems if the oil level is too high.)
I live in Michigan, and once my first year break-in period using Suzuki's 10w-40 non-synthetic oil was over, I began using Yamaha's 10w-50 Semi Synthetic oil with great results. (I think it's called YamaLube.) My '96 seems to run smoother, better and quieter in all temperature ranges with the semi-synthetic oil. Either use non-synthetic oil, or semi-synthetic....I wouldn't recommend full-synthetic.
Tim