I don't want a flamewar, Just information.

Prophet

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Hello fellow tossers, dentists and miscreants.

I know starting a thread about Oil will start flamewars, but that's the problem. I've read through 20 years worth of arguments and I'm no further to understanding than I was before I started reading.

I bought this Oil to change my R1150GS's oil since it hasn't been serviced in who knows how long. https://www.ebay.co.uk/itm/111701579402

It's 20w50 Mineral oil, and from what I can see that's kind of the consensus, but I don't know if the API specification is wrong on it, some people said it doesn't matter what oil you put in it, some people say it does. I don't know. It's SG/CF API.

Just I've used this brand before in my old bikes and never had an issue with their oil, it performed well enough.

Thanks.
 
Co pilot response.

API SG/CF is completely fine for a BMW R1150GS.
The R1150GS "Oilhead" engine relies on older, traditional oil chemistry, making this specification a solid match:
API SG (Gasoline Spec): BMW originally specified API SF, SG, or SH for the R1150 series. API SG is high in ZDDP (zinc and phosphorus), which protects the R1150’s flat-tappet cam followers from scuffing and excessive wear. Modern automotive oils (API SN, SP) reduced these anti-wear additives to protect modern car catalytic converters, but SG retains the heavy protection this engine likes.
API CF (Diesel Spec): The "CF" rating indicates heavy-duty detergent and dispersant additives designed to handle soot and thermal breakdown,
 
Your mineral 20W50 oil is just fine for an agricultural tool like the 1150 GS..
She makes noise and rattles even when warm, thats all normal…
Watched a documentary on BMW building the 1000 RR in Berlin Factory.
Those engines are made to 7 micrometer tolerances, just imagine a human hair is between 20-40 micrometer.
They need highly specified oils…..not the 1150…..I have used a 10W40 semi as top up,
but stick to mineral 20W50 for an oil change.
No problems.
 
Your mineral 20W50 oil is just fine for an agricultural tool like the 1150 GS..
She makes noise and rattles even when warm, thats all normal…
Watched a documentary on BMW building the 1000 RR in Berlin Factory.
Those engines are made to 7 micrometer tolerances, just imagine a human hair is between 20-40 micrometer.
They need highly specified oils…..not the 1150…..I have used a 10W40 semi as top up,
but stick to mineral 20W50 for an oil change.
No problems.
A 7 micron tolerance is a reflection of the capability of the manufacturing process. (And sounds a bit tight to me, as process capability studies require that to allow such a tolerance the process would need to be capable of achieving less than 4.2 microns in normal circumstances - typical CNC machines are around twice this - though grinding processes can achieve it in normal production)

It has nothing whatsoever to do with the clearances between parts, which is much more relevant to the oils.
 
It's 20w50 Mineral oil, and from what I can see that's kind of the consensus, but I don't know if the API specification is wrong on it, some people said it doesn't matter what oil you put in it, some people say it does. I don't know. It's SG/CF API.
There is no easy answer to this one !! as Its the everyone has an opinion / Asshole type of thing

But My tuppence after working on them for 20 plus years, CF is pretty much all that is "easily" available these days and even that is becoming hard to get and all of my bikes have run on it for 20 plus years

If you are going to keep the bike ??Try your local motorfactors and ask them to get you a case of 4, OR a 20 litre drum of an SG grade If you are not happy with SF

Personally again!! If you are just riding the bike and not riding it like you stole it every minute of every ride ??

Fresh oil of and adequate amount is way better than low oil or Dirty oil and if you have doubts change it at 4000 rather than 6000, Its your call
I ran my 1200 on that grade too !


Oh and don't keep filling the oil level to full !! Park it on the sidestand after a run and let it drain down a bit from the oil cooler!
If you can brave it out? They find their own oil level Where they basically stop using oil so much !!

There are two half litre paint pots flying up and down and the crank smashing the oil surface and basically vapouring anything that is in their way

My 1200 was a prime example even though I should know better I was worried about fragile the Mk1 were

And I did the religious top up thing and ended up at about a litre and a bit between each service

Caught myself on when my mate reminded me of the above and that dropped to "maybe" a 1/4 litre between services !!
 
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I don't think that it's nearly as critical as people try to make out. The manual itself gives a wide range of oil viscosities.

For my own part I will use anything from 10/40 to 20/50 either mineral or (more normally) semi-synth and they don't seem to suffer from it. I ride mine every day is all weathers and temperatures, a lot of stop-start (because it's a mix of fast road and London traffic), I put 82k on my last bike and it's still going strong 2 owners on.

By far the most important thing is to change it regularly.
 
I ran my first hexhead on viscositys ranging from

water to grease (well not quite grease)

The understanding was its a tractor and is more than happy on mineral oil, you can run SS but why bother

specified thickness was 10/40 with lots of up and down in the thickness ratio supject to the minimum letters

i ended up on 10/50 with the correct letters ( some strange info on the letters) ?? the llater the letter covers the the preceding letter ?

Anyway being a tractor it didnt care and it became no longer noisy when we got to 27 degress c
 


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