This topic I’m quite familiar with. In the Beemer MC forums this turned into heated debates. Some of these guys and gals sphincters are so tight... well you get the picture. It’s been some time since I was in a Beemer forum, but as I recall BMW advised dealers not to use syn oil in bikes under warranty. Regardless of this warning many owners including myself use 100% syn oil in our horizontally opposed big twins.
Contrary to some beliefs, it’s ok to use 100% synthetic motor oil in older cars. The most common misgiving is it can’t be used with conventional. That use to be true with synthetic back when it was a relatively new product. The synthetics of today are found on the market as blends of syn and dino.
Synthetic oil is superior to conventional oil in many ways. It doesn’t break down as quickly as dino, and it has better adhesion to critical surfaces. That’s why oil change intervals are further apart, and start up is much easier on effected parts. The one draw back I personally experience is syn does seep past older gasket materials faster than dino. I almost forgot, syn oil also has a broader range of viscosity.
I will not argue the point of the oil for diesel motors. Vikki covered the points of using these dino oils. Like she said, buy’em up now for those will fade into history thanks to the EPA. Thanks for the tip on STP Vikki. I didn’t know it still carried a percentage of zinc.
As far as brand goes, that’s up to you. Different folks have brand loyalty; others don’t give a rats ars. I prefer Castrol. I use the syn blend 10-40 in the convertible, and I use the Castrol dino 10-30 (in winter) and 10-40 (in summer) for the cammer. I’d use the syn blend in the cammer, but I have to get it sealed up better. It likes to leak that undercoating and it’s less expensive than syn blend.
