XR600R Knocking ??? Or just noise ???

I have a 1993 XR600R, stock everything and recently rebuilt the engine, new just about everthing :D !!! The bike runs flawlessly, starts easy, etc. I have 15/48 gearing :) ... When I open it up on the highway, full throttle, I detect maybe some different noise, but barely, cant tell what it is :) . But againhere is so much wind, chain noise, etc. at this speed I would barely hear a truck horn :p , let alone knocking. At full throttle, the bike just goes very fast, and power RPM's and power just seem to run out, but its smooth, no missing or anything, but there is a sound thats just a little different as I advance the trottle to the full open position... Im afraid to run it at full throttle for very long, because I dont want to destroy my engine if it is knocking :D , how can I tell ???

My guess and nothing but a GUESS is possibly valve spring tension or a lack of. The installed height after a valve job changes usually increasing spring length and decreasing tension. Springs weaken with heat and age at high RPM they have a tendency to not follow the cam causing a rattling sound. If all the components were inspected and clearances checked when it was assembled, My GUESS is springs. The best way to find out how your engine is wearing normal/abynormal is the oil and Filter. Take the oil filter and wrap it with paper towels to draw out the oil, this might take a day or two. Cut the ends off stretch out the filter and look for fiber and or metal. A little is normal allot is a sign of things to come.

Dont remember if I bought new springs or not, dont think so :) . The sound seems to change more with full throttle than with just rpm. Anyone out there know how to hear a knocking motor :) with so much other noise going on ???

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