BMW R1200R R1150R/T F800 K1200R R1100R/T R1250R RnineT Message Board

This is the most comprehensive article that I have recently read on the subject. Well worth reading for those that want to dwell the latest on the subject, albeit a bit long. Note that it addresses water cooled IC engines with better temperature control, but is equally applicable to air cooled engines.

http://ferrarichat.com/forum/faq.php?s= ... oil_basics

There are three things to remember, which by the way are not new to the tribology:

Oil flow is what is required and pressure drives the flow
The golden rule is 10 psi per 1000 rpm
90 % of the wear occurrs during start-up

It would be especially welcome by owners with hard to start bikes in colder climates, read on.

Enjoy

Wow. Very cool writeup. Also clearly implies why it's necessary to have an oil pressure gauge.

Other major points in the article:
- Use the thinnest oil you can that will still get you sufficient pressure at operating temperature.
- Synthetic oils have a big advantage in lubrication during start-up.
- Higher pressure due to viscosity increase (thicker oil than necessary) actually results in less oil flow, less lubrication, less cooling, less horsepower. So, seems that an "oil cooled" bike would really benefit from not using too thick an oil.

Ves

You are a man that apreciates the fine details.....there is something to be learned everyday.

I have a 99 MB E430, 295 HP running Mobil 1 0W40 and it returns 27+ mpg at 80 mph on two trips to FL. My 77 911 runs ~ 10 psi at idle (900 to 1000 rpm). I'm going to install an oil pressure gauge on the Burgman and see what can I get away with.........will take to the dyno too.......I'm thinking 0W40 or 5W40

Ford has taken this course as well, the oil recommended for my 06 Mustang GT is 5W-20. Contrary to what we used to believe (thicker is better) the new thinner lubes flow better cold, and hold up against pressure. The Stang also gets mileage numbers similar to your MB.
Don

Since I don't have my R1150R anymore I'll have to talk to CycleRob or Boxer to see if they want to try some of the "thin" oil as I'm willing to give them the oil. In any event I will try it in my Burgman, unfortunately I changed the oil 2 months ago, so it will have to wait.

Al,
Rob has used the Castrol Syntec 5W50. I have too. It is definitely better in the colder weather than the Mobil1 15w50 that I am currently using, and much better than the 20w50 dino that I have used. I am due for an oil change soon, and will probably go back to the 5-50.

Very interesting article. But, for the last 30k miles I am using Amsoil "DOMINATOR" Racing oil 15W50.
I see no reason to clean my engine from the inside.
One of my riding buddies is using same racing oil in his Old BRICK engine for over 100K without any problems.
Boxer engine is designed to run on 20W50. In the COLD weather I would go from 20 to 15 or 10, or 5, but to change from 50 to 40

OK, so let me throw this into the mix...

based upon this article, we should consider using this....

http://www.iapdirect.com/product.php?productid=42015

Yes, thats right! A 0W50 weight Synthetic Oil. No, its not SG rated and yes they are very proud of it to at $10.00 a quart.


Anyway, I would be interested to know how hot my oil gets during those very hot (97 and up) and humid summer days when traffic is not moving along as I would like. I may have to look at install one of those oil temp gauges after all...

klrstix
Where in Louisiana are you located? We might be neighbors.......

OEM's have selected a viscosity of 10 at an operating temperature of 212 F to be the basis for thei IC The key thing to remember is the viscosity selected by the OEM designs the engine to run at normal operation temperatures and that is assumed to be a viscosity of 10 at 212 F. The other aspect is the flow of oil to the lubricated parts and that is accomplished by pressure as the motive force. The rule of thumb is 10 psi for every 1000 rpm.

That being said the above is easily accomplished in water cooled engines as they are designed to run in the 200 degree range. In the case of air cooled ones, obcviously one would benefit greatly from both a temperature and a pressure gauge. Although one could get away iwth a temperature gauge alone.

The bottom line is to figure out what is the maximum temperature of the oil under the conditions you state and then choose the oil accordingly. I will venture to say that in heavy stop and go traffic the 20W50 dino is marginal at best, especially if the temperature hovers around 240 F. After that a lighter oil could be reducing friction, which reduces temperature and possibly gain a little HP. It's all in a days work.......

Hello Boxermania...

I actually live in the upper northwest corner of our beloved state. In the wonderful Shreveport/Bossier City area. So we aren't quite neighbors!

As for the oil, I use the 5w50 Castrol from December to May. Then in June I switch to the Mobil1 15w50.

For my next "project" I will probably look into installing an oil Temp/Pressure gauge. I admittedly fight off the urge to obsess over these sort of things but given a good deal of my riding (which is year round) is a 13 mile commute to work I would benefit from the info this gauge would provide.

Finally, let me say how much I appreciate the contributions everyone provides from your knowledge and experience. Thanks!