BMW 10W40

[kinchy]

I changed the oil and filter on the RT today. Had to use 10W40 BMW motorcycle oil (thought we had 20W50) Later checked the owners manual and it suggests 10W40 shouldn't be used over 70 degrees. I don't need to be concerned about this do I?

[ShovelStrokeEd]

Short answer, no.

 

Long answer.

 

So long as you are not operating the motorcycle at extemes of load and HP requirements your bike will be fine with 10w40 in the crankcase. The other extreme might be considered lots of idling and slow running in traffic where the oil cooler cannot really cope with the heat loads and the oil gets pretty hot, i.e. >7 bars on your RID.

 

Facetious answer.

 

Your motor can't read. If you don't tell it that you have 10w40 in there, it will probably never know.

[smiller]

BMW themselves specify that 40W is OK in an RT for all temperatures, if it is a synthetic ('Special') oil. Take a close look at the manual.

 

But synthetic or not, Ed gave you the right answer(s).

[Urban Surfer]

What about Amsoil 0-40 synthetic. I'm running that right now and the bike runs really good, starts easy and never seems to get really hot.

[ShovelStrokeEd]

See the facetious reply.

 

The specifications (from Amsoil's site) indicate it is a suitable replacement for 10W-40 and it should be fine.

 

Something all would do well to keep in mind. There is considerable overlap and overhead in oil specification from one viscocity range to another. High quality oils from major suppliers, so long as they are changed regularly and properly filtered should present no problems. Within reason, so long as an oil meets BMW's recommendations for API classification (SF, SG, SL, etc.) you should be fine.

 

That said, if you contemplate hour upon hour of 120+ mph running, you might want to consider a heavier oil. For just putzing around in the 35 to 75 mph range that most of us spend the majority of our riding time, usually with no more than 25% throttle openings, the fact that oil is present is more important than the quality or viscosity specifications. Please don't use the foregoing as an excuse to start yet another oil level thread.

[Red]

I've used 10-40 for ten years and 66,000 miles and have had no problems except in extreme cold. Can't keep the engine temp in the operating range.

[kinchy]

Thanks Boys..

[RFW]

What about Amsoil 0-40 synthetic. I'm running that right now and the bike runs really good, starts easy and never seems to get really hot.

The viscosity of oil you are using has nothing at all to do with it "getting hot" or not.

 

Bob.

[Acidburn]

What about Amsoil 0-40 synthetic. I'm running that right now and the bike runs really good, starts easy and never seems to get really hot.

The viscosity of oil you are using has nothing at all to do with it "getting hot" or not.

 

Bob.

 

Really, what then,, the direction of the earths rotation?

 

Sometimes the Amsoil guys will share the vis index for a given blend with you, then you have real data, temp / vis index, otherwise its black magic.

We are all running the high end racing synth yes, dry clutch means we can run the super duty oils and dont need to worry about the friction modifiers like the wet clutch folks do.

I may have missed that small point in this thread, but if not, it is a important a point as the weight and time you change the oil.