Engine oil?

[beemer]

I put in 20/50 in my bike but i think it's too think for here in the UK,it's turning over very slowly and i can make the battery flat easy,what do you recommend guys?

[Bob_Roller]

I keep 20w50  weight oil in my bikes all year round, I realize that winter in Phoenix is quite mild compared to a lot of locations .

My bikes routinely get left out at work for 18 hours in temps of the upper 30's F to lower 40's F, and I have no problem starting the bikes .

The 1150 oilhead uses the same battery as the R65 .

How old is your battery ?

I've got  22ah AGM type batteries in all of the bikes .

[beemer]

Yep it could be time for a new battery,i'm going to remove it and use my jump start battery connected right to the terminals and see if it's slow turning the motor then,if it is,i will have to look further into the problem,i was thinking of at least 22/24 amp battery,not sure if i should get a gell type or standard,what do you think?

[Barry]

I've used 10W40, 15W40 and 20W50 over the years. I believe 20W50 is too thick for year round use in he UK especially for when I have been riding the bike at temperatures down to -8 Deg C. I do not intend to ever use 20W50 again.

In general I think we worry too much about the oil being thick enough when the engine is hot. We should be more concerned about it being too thick when it's cold because that's when the wear takes place. I've settled on 15W50 because it's only slightly thinner than 20W50 when hot but half the thickness when cold. It's also very easy to find a dual rated diesel/petrol heavy duty oil which gives me some confidence in it's anti wear properties. 15W40 is also approved by BMW for use up to 30 Deg C. To tell you the truth I think 15W40 is still too thick for my bike because it runs very cool oil temperatures. If it wasn't for all the fuss about ZDDP I'd choose a 10W40 oil in a heartbeat because it's even thinner at cold start temperatures. BMW also approve of 10W40 up to 30 Deg C provided it's "enhanced" oil whatever that means. I'll Have to dig out the Service bulletin to check the exact wording.

In the attached bulletin it's not enhanced but "special" oils and I still don't know exactly what that means. Almost certainly it's something to do with high temperature shear strength. For a 10W40 that likely means  synthetic because even even though 10W40 and 15W40 oils are nominally the same viscosity at 100 Deg C for mineral oils the 15W40 usually has a better high temperature shear strength. In other words it has a bit more in reserve. I guess what that boils down to is if you are going to use a 10W40 don't use a cheap one. You can say that about any oil but I think it's particularly important for a 10W40.

Note the bulletin says 10W -X  where X is equal to or greater than 40
so it could be 10W40 or 10W50 which alone tends to spell synthetic.

[beemer]

What make of oil do you use Barry?

[Barry]

What make of oil do you use Barry?  

Well I'm not going to say because that would tend to turn this into an oil thread and I'd rather oil was chosen on a scientific basis. I will use any 15W40 that meets a minimum spec of ACEA A3/B3. A3 mean it's a high performance petrol oil and B3 means it's suitable for light duty (as in passenger car) diesels. You will also find A3/B4 which is better still.

[nhmaf]

I've similar (or colder) climate as the UK, and I never run 20w-50 in anything anymore, 10w-40 is quite thick enough!

[beemer]

I've similar (or colder) climate as the UK, and I never run 20w-50 in anything anymore, 10w-40 is quite thick enough!

Yep i'm with you,10/40 is my choice.