Can you mix regular and synthetic oils?

[roncg41677]

My oil light keeps coming on on my 93 Seca 2. It will stay on for about the first 4-5 minutes of my daily ride to work, then go off. Haven't checked the oil yet, it's a 2 person job; the sight glass is not in a convenient location.

If the oil is low I just want to add some for now until I have time to do a full oil/filter change. I just got the bike and I don't know what the PO used. If he used synthetic and I add some regular bike oil to the crankcase could that cause any damage?

Thanks!

[Johnj]

Maybe you should go ahead and change the oil. Then you'll know what kind of oil is in it.

[HYPERR]

My oil light keeps coming on on my 93 Seca 2. It will stay on for about the first 4-5 minutes of my daily ride to work, then go off. Haven't checked the oil yet, it's a 2 person job; the sight glass is not in a convenient location.

If the oil is low I just want to add some for now until I have time to do a full oil/filter change. I just got the bike and I don't know what the PO used. If he used synthetic and I add some regular bike oil to the crankcase could that cause any damage?

Thanks!

Yes you can mix regular and synthetic oil.

As for checking the oil, how is it a two person job? My CBR has the sight glass all the way on the bottom and not only that, it is recessed and surrounded by the fairing. The only way to check it is to squat down completely while holding the bike upright to see it as it is so low. Still I don't see how any oil check has to be a two person job.
Anyway, if it is, then get one of those dentist type mirrors with the long handles and you can check the oil level while straddling the bike.

[roncg41677]

Maybe you should go ahead and change the oil. Then you'll know what kind of oil is in it.

That's plan A, Plan B is don't miss a day of this gorgeous riding weather. I'm going with Plan B . Until I can find/afford the one filter that will apparently fit with my aftermarket headers.

As for checking the oil, how is it a two person job? My CBR has the sight glass all the way on the bottom and not only that, it is recessed and surrounded by the fairing. The only way to check it is to squat down completely while holding the bike upright to see it as it is so low. Still I don't see how any oil check has to be a two person job. I'm so confused...
Anyway, if it is, then get one of those dentist type mirrors with the long handles and you can check the oil level while straddling the bike. Mr. Green

Okay, chalk that one up to laziness. I just went out and checked it and I was able to do it alone. For some reason I thought I had tried that before to no avail.

Thanks for answering my question! I've already got a quart of 10/40 motorcycle oil I can use for now, not synthetic. The oil was almost exactly halfway between the low and high markers, so, fine I guess, but it was pretty dark. The PO said it would be due for an oil change soon anyway. After checking the Seca forums, apparently the light will come on when the oil is below about 2/3 up on the sight glass. I'll add a bit and see what it does.