Topic: Which Engine Oil

[clintcd]

Can anyone tell me which replacement engine oil to use in a 1977 cb750a, Haynes manual lists Castrol GTX  for all cb750's including the hondamatic, is this correct?, can the "A" take synthetic or semi synthetic oils

Thank you
clintcd

[trueblue]

I personally run Lucas 10w40 semi synthetic in my 650, I like it.  The bike seems to as well but I can't comment on the A's.  
One thing you will learn on this forum is opinions are like arseholes (especially when it comes to oil), everyone has one and most of them stink .  Oil threads are boundless if you do a search and most of them are full of crap.  But now I will just pull out my popcorn and watch.

[70CB750]

It can take synthetic. but after a while - say few years - it will leak.  The reason is the excellent ability of synthetic to cut crud - it will remove deposits in gaskets and make them leak.

I personally have synthetic Mobil 1 15W-50 in my K0 as of now - for the summer and fall - and the plan is to go dino again.  Some folks run semi synthetic too.  When I run dino, I use Mobil Delvac - oil for diesel trucks.

[raymond10078]

http://forums.sohc4.net/index.php?topic=105638.0