R90S engine and gear oil

[skychs]

1975 R90S

Its time for fluids.

Sensitive topic I know .... so lets not go there. Im just curious what everyone is using.

I run Valvoline VR1 20-50 in my R60/2. Its a popular go to oil for vintage and antique bikes for various reasons. Is anyone else running it their /6's?

For tranny/gear oil .... I run the Sta-Lube GL-4 hypoid 85-90. Same thing. It would be nice to use the same fluids in both my bikes.

[schrader7032]

I've not run the VR1 but I understand that it is recommended by Vech. I tested nearly 20 different brands of oil about 5 years ago. VR1 has a good amount of ZDDP included. The best oils for ZDDP were Golden Spectro 4 and BMW's oils. I've mostly run BMW oil in the past 8-10 years, but now BMW is no longer offering 20w50 but a 15w50...I said no thanks. I just changed my oil this week in my /7 and put in the GS4.

As for gear oil, the only reason you would consider running GL4 is for the possibility that the older transmissions might have more bronze/brass inside. That was somewhat of a problem with earlier bikes, but honestly I don't see /2 machines falling apart on the roadside. But for /5-on bikes, that is not an issue. Owners manual says to use a good quality GL5 oil. My manual says 80w90. I think you should consider GL5 for the R90S since it stands up better to the higher pressure of the helical gears.

[skychs]

I've not run the VR1 but I understand that it is recommended by Vech. I tested nearly 20 different brands of oil about 5 years ago. VR1 has a good amount of ZDDP included. The best oils for ZDDP were Golden Spectro 4 and BMW's oils. I've mostly run BMW oil in the past 8-10 years, but now BMW is no longer offering 20w50 but a 15w50...I said no thanks. I just changed my oil this week in my /7 and put in the GS4.

As for gear oil, the only reason you would consider running GL4 is for the possibility that the older transmissions might have more bronze/brass inside. That was somewhat of a problem with earlier bikes, but honestly I don't see /2 machines falling apart on the roadside. But for /5-on bikes, that is not an issue. Owners manual says to use a good quality GL5 oil. My manual says 80w90. I think you should consider GL5 for the R90S since it stands up better to the higher pressure of the helical gears.

Thanks Kurt. Good advise. I will start looking into the GL5's. Thanks

[wolds]

been running Brad Penn 20-50 in myR60/6 aand R90S without issue for several years. Great oil for air-cooled boxers and is the "go to" oil for air-cooled Porsche's. The way I see it the BMW boxer is just a slice of a flat six, same technology.

[skychs]

Im finding two different oil filters for the R90S. There is a one piece and a two piece (folding) filter. Why the difference and is one better than the other?
thanks

[schrader7032]

The one piece is the original design. They came out with the two piece or "bendy" filter to make it easier to get in and out in some configurations, say with lowers like the RS and RT. Be advised there are filter lengths for with and without an oil cooler.

I would suggest that the two piece is the better filter. Sure there is some loss in filtration area, but I'm pretty sure the amount of area was an over design to begin with. The reason it's better is that with the metal ends that butt up in the middle actually make the unsupported length of the paper element stronger and less likely to collapse.

[skychs]

The one piece is the original design. They came out with the two piece or "bendy" filter to make it easier to get in and out in some configurations, say with lowers like the RS and RT. Be advised there are filter lengths for with and without an oil cooler.

I would suggest that the two piece is the better filter. Sure there is some loss in filtration area, but I'm pretty sure the amount of area was an over design to begin with. The reason it's better is that with the metal ends that butt up in the middle actually make the unsupported length of the paper element stronger and less likely to collapse.

Thanks again Kurt. Much appreciated. I learn something new about BMW's every day.

[ksiemon]

Use the one piece. Why screw around with the hinge? One more place to leak. I do have a RS with a cooler and that one gets the two piece type. The "S" gets what the Gods want, the one piece!. Also check and make sure there is no old o-ring in the block on the tube. When they were new you had to install o-rings to seal the filter. As you know the new ones come with seals on the filters.

[tobydog61]

Just did an oil change on the R90S and my BMW dealer is now carrying a non-synthetic dino BMW oil for vintage bikes, 20W-50. Comes in an old style metal can with a screw on cap. I believe someone told me Spectro makes if for them. I went with it because I could not find Spectro in my area in 20W-50. Price was reasonable.

[schrader7032]

As far as I know, Spectro only comes in plastic bottles. I used to use BMW oil in my /7 but when they went from 20w50 to 15w50, I said no thanks. I also cannot find Spectro locally, so I ordered from Amazon...got here pretty quick. Spectro is by far the best oil out there for ZDDP content.

I did an oil test a number of years ago and after my test was done, it was noticed that Porsche came out with a 20w50 dino oil in a metal can. One of the guys sent that oil off for analysis. It tested reasonably well however it had elevated levels of iron/steel in the content. Most likely from the metal can. Personnallly, I'd try to find Spectro. Or consider Valvoline VR-1 which is readily available.