Motorcycle Repair: engine knocking/oil filings in filter yamaha 650xs, chain tension, cam chain

Question
Hey Chris,
   I have just recently purchased this 1983 hertidge special 650 this summer.  After fixing a bunch of carb prob's and general maintance I have put about 1000 km on the bike. I have always heard a small rattling noise when driving and contributed it to the double wall headers and those cheap slip on mufflers.  Recently I have started hearing a slight "knocking noise" from the engine and when I changed the oil I found metal filings in the oil filter and of course a hole in the oil strainer in the lower pan.  Are these filings causing the knocking or the knocking causing the filings. Maybe cam chain?

Answer
Hi Keith.
 Considering the age of the bike and the other factors that you had mentioned, it could be any number of things, including those that you mentioned, that caused the shavings.  Whether you have a critical problem with that or not depends on whether there were a lot or a little shavings.

 The knocking is unrelated to the shavings.

 Start by checking the cam chain tension and the valve gap and timing.  Those could cause knocking if out of spec.

Good luck.
FALCON