An Oil thread worth reading

[Barry]

I have no problem at all with oil threads provided there is some intelligent discussion going on and that was certainly the case in a recent thread on the Boxerworks forum. It was actually about crushed oil filters and that caught my attention at first because I've BTDT with my own crushed filter.

Then a guy posted a link to "Bob's the oil Guy" website. I'd visited this site before though not recently. This time I took the trouble to read everything he had to say on oil viscosity (11 chapters or about 30 pages of A4).  I'd come to the conclusion years ago to use something thinner than 20W50 oil in my airhead so maybe I was predisposed to like what he had to say. This guy makes a very persuasive argument about why thin oil is good and thick oil is bad by talking about oil flow rates as well as oil pressure and I particularly liked the way he puts his money where is mouth is by making his own decisions on what viscosity of oil to use in his new Ferrari.

Highly recommended read if you haven't already done so.

http://www.bobistheoilguy.com/cms/

[Motu]

So airheads would last even longer if we used thin oil? They don't seem to die prematualy from using 20/50.The thick/thin oil debates on BITOG are like oil or gun threads on other sites - pages and pages of them defending thin oil,when no one taking the opposing view.Thin oil is a US thing - they have to use thinner oils for some ecconomy thing.The rest of the world has no laws requiring thin oils,so manufacturers can choose and oil that suits.ACEA is the European standards which are more complex than just the SAE or API stanbdards.

BMW recommends 20/50 for my climate...I'll stick to that.

[Bob_Roller]

I was in a local store to get oil for my four wheelers, oil changes are done in October when I'm on vacation .

 The different weight oils that I saw for Mobil 1 shocked me, there were 0-30, 0-10 and 0-5 weight oil !!!!!!!!!!!

Especially for the climate here in Phoenix, I use 15-50 in the cars, and 20-50 in the bikes all year round .

I must be stuck in the 'stone age', as a light weight oil like that would never go into a vehicle of mine .

[nhmaf]

New cars these days are specifying these new high tech, very low viscosity oils.  I think that our Mazda specifies 0-30W.   The tolerances and low friction surface treatments on many internal engine parts these days enable use of these low drag oils for higher fuel mileage.

[Barry]

The thick/thin oil debates on BITOG are like oil or gun threads on other sites - pages and pages of them defending thin oil,when no one taking the opposing view.

Good point. It would be good to see an opposing view at the same technical level as Bob himself.  The actual forum on that site was disappointing and I wasn't recommending anyone read it only Bob's 11 chapters.

I'm in a temperate climate where BMW's chart says 15W40 is just about OK. There's no way I will ever put 20W50 in the bike again and start it in sub zero deg C temperatures when 15W40 is half the viscosity of 20W50 in such cold conditions.  On the other hand the difference between these two oils at operating temperature is negligible which is one of the points Bob is trying to make. He's trying to say quit worrying about your oil when it's hot as long as you have good pressure and start worrying about it being grossly too thick when it's cold which is when most of the wear takes place.

[Motu]

The oil chart in my manual gives 20/50 as being in the range of -10 to 40 degrees - those are the extreme ranges in our climate.Most riding would be done from 10 to 30 degrees.

I'm using 25/50 - so long as I don't start the bike below 5 degrees I reckon she'll be right.

[Semper Gumby]

I'm about to change to "Winter" oils here in Atlanta.  I'm going to put 10W40 in this year to make it easier to start on those cold nights in the company parking lot after a four day trip.  In April I'll go back to 20W50 for the spring and summer.  

For the tranny and the drive train I use 85W140 in the spring summer and fall and then switch to 80W90 for the winter.  Both are Synthetic Blends.  The motor gets Spectro Golden American and the drive train gets Valvolene in the dark blue bottle.  Been that way for many years now.  I use the BMW flexi-filter and two washers to hold the proper pressure (after measuring the depth of the oil filter canister) on the big o-ring and no paper gasket.

Your results may vary.

[Ed Miller]

Bob, I used 0w-30 in my CRX, and it only got to 280,000 miles before I skidded off a corner and flipped it, back in August.  I think I should have used a better driver.