Should I put special motorcycle oil in my 1975 motorcycle?

I have a 1975 Honda CB550 K1 and I figure they didn't make special motorcycle oil back then, so I'm wondering if I should use regular car oil. On the dipstick headpiece thing it says ';SAE 10W40';


Which type of oil would it be best to use?


ThanksShould I put special motorcycle oil in my 1975 motorcycle?
I use Castrol GTX 10W40 in my Hondas.


I have never had an oil related failure. Actually, they all looked real pretty inside.





If you think you may have a concern with ';friction reducers'; just make sure whatever you get does not have the ';energy conserving'; label.Should I put special motorcycle oil in my 1975 motorcycle?
ANY motor oil you can buy is more than sufficient for your bike. I too am partial to Castrol GTX, mainly 'cause it saved a couple of engines for me. Regular oil and filter changes mean a LOT more for engine longivity than the type/brand of oil you use. I use 20W50, here in SoCal we don't get cold enough to nee 30W!
Careful...the newer oils have additives that were not available back in 1975. These additives were are not designed to be used with a wet clutch system used on your bike and may cause the clutch to slip. Autos use a dry clutch system that require an oil/grease free atmosphere.
Use any quality, brand name, 4 stroke motor oil.


';Motorcycle'; specific oil is just a marketing ploy to purchase that manufacturers oil.


I use Castrol GTX in all of my bikes., including the crankcase of my 2 stroke bikes.
For the age i would use a heavy weight oil like a 50 weight.Thats what i use on my harley use harley oil its the best and lucas or royal purple. Its really what you pref.
sae 10w40 is regular car oil.-----just use a good oil,castrol,valvoline etc in a 10w40.i wouldnt go heavier unless you are burning oil.