Topic: Some CB550 oil questions

[Mitchm114]

Hi everyone.

I have a 1974 CB550 with 22k on it. I recently took a 700 mi roundtrip down to VA & back from Ohio.

A couple things piqued my interest and maybe cause for concern, but I'd like y'all's perspective.

1. My oil pressure light would stay on once I had the bike warmed up, but only when under 1500 rpm. I can make it go away at idle but only if I rev above 1500. My oil level was between the two marks on the dip stick when I would stop to check it when it happened. It only happens when the engine is warm. I've heard this isn't an oil level issue, but rather a pressure issue, but I'm not sure where to look. I don't have any noticeable oil leaks or anything except a tiny bit around the head gasket, but nothing hits the ground.

Any cause for concern here? Things I should check?

2. At the end of my trip, I checked my oil and it had dipped below the lower mark on the dipstick after that long ride. Does this mean that I'm due for some engine maintenance (rings, etc)? Anything else I should look at?

Thanks in advance for your help.

Thanks again,
Mitch

[TwoTired]

The oil light is supposed to come on when the pressure fall below 7-5 lbs.  But, thats' when new and know functioning properly.  Oil pressure can go lower from oil pump wear, a clogged oil filter, as well as crank and rod journal wear.  But, nothing is of concern until you KNOW that the pressure is actually going to low and that that you don't simply have a a failed sensor.

Lastly the choice of oil, oil additive package, and grade can matter, as well as oil that is damaged by excessive heat and thrashing by trans gears and mechanical cutting of the long fibers that make the oil behave as a higher viscosity oil and resist running out of fiction surfaces.

Oil lights coming on bother me.  So I generally make sure it is telling the truth before a big panic.  Especially if the motor is not leaving a blue cloud behind it. OR oiling  the inside of the exhaust.  If the motor has been treated with proper oil changes in its service life, 22K miles is nothing to be concerned about.  But, if it's had 2 oil changes or less since new...not good.

Cheers,