Ozbloke, good topic. All good replies also.. On my recent problem, abrupt low oil pressure with good return. Red light flickering. As suggested I made up and oil pressure gauge. I was recording 30 psi at 3000rpm rather than the 60-65 psi suggested. At idle 15psi rather than 20-30 psi. After reading posts I decided to renew my oil pump, oil pressure switch and oil regulating valve. Machine is 27 yrs. old with 10000 miles. It's been well maintained and exercised regularly even though ridden seldom, until last 2 yrs. I inspected the parts and noticed 2 areas of concern. The primary side of the pump, the ball seat was not as near as pronounced as the return side was. Everything else about the pump seemed ok. I reseated it and bagged it as I have done all parts of this bike. I pneumatically tested the oil pressure switch, but replaced it anyway. The main problem I found was the oil regulating valve was scored and would not seat completely. I check this by lightly squeezing oil into the oil passage coming out of the oil drilling. This was allowing oil the least of two paths of resistance, the bearings or right into the crankcase return, resulting in reduced oil pressure. Oz' like you said maybe this will help someone down the line. I immediately started running 65-70 psi o. p. So if I was to do this again I'd check the o.r.v. and replace it.i
