Technical OIL Question

I noticed on a recent post that the 2007 manual says to use 10W30 motor oil. However, my 2006 manual says to use 10W40 weight? Did Honda change their requirement for all Silver Wings, or just 2007 and beyond? Or, can I now buy 10W30 instead of 10W40? Any help is greatly appreciated.

Dennis,

I wouldn't lose a lot of sleep over this issue. I have two 2005 owners manuals in front of me -

Specifications Section on page 196, engine oil recommendation -
API Service Certification SG or higher except oils labeled as energy conserving on the circular API service label, SAE 10W-40, JASO T 903 standard MA or MB, Pro Honda GN4, HP4 (without molybdenum additives) or HP4M (with molybdenum additives) 4-stroke oil or an equivalent motorcycle oil.

A better (clearer) reference is found on page 109 (2005 manual) where the viscosity that is recommended is SAE 10W-40.

Again, I would not lose much sleep over using 10W-30, it is a little thinner, but should not result in engine damage. Changing at a recommended interval is the key. Honda recommends an initial change at 600 miles then at 8,000 miles with an interval of 8,000 miles between subsequent oil changes. If you are changing more frequently (most do) 10W-30 will not have a significant effect on your engine.

Thanks Dale,
I am really only interested because I have hearing good things about the new Castrol Edge:
http://www.castroledgeusa.com
But, it only comes in 5W30 or 10W30. Then when I saw that the 07 recommended 10W30 I figured I use use the Castrol? Yeah???

Actually the last time I changed oil in both bikes I used Honda brand 10W-30 synthetic.

Oil has 4 primary purposes Lubrication, Cooling, Additives bond with unburned hydrocarbons which are carried to the filter, and...

Who knows the fourth purpose?

I think you should be able to use the 10W-30 with no detriment to the engine. Just stick to a schedule to change oil and filter. Don't have to be crazy about it - 500 miles +/- is not that big of a deal.

I found an interesting website and this person is saying that all 10w20's are "energy saving" which has no effect on the Silver Wing but the manual says don't use it? Interesting don't you think?
Engine oil
Executive summary: The commercial grade oils are clearly superior to the mass market oils. For the best protection in your bike or car, use Shell Rotella Synthetic, available at Wal-Mart in blue containers for $13 / gallon. For the best petroleum oil you can buy, get Shell Rotella T, Mobil Delvac 1300, or Chevron Delo 400, about $7 / gallon at any auto parts store. On the back of most oil cans is a circular stamp with the certification. Avoid oils that say "energy conserving" in the bottom half of the donut. These oils contain friction modifier additives that could cause clutch slipping over time. All XXw-20 and XXw-30 oils are energy conserving, and should not be used in your motorcycle. 10w-40 oils should not be used in a motorcycle that runs the engine oil through the transmission. Don't buy any oil additives like STP or Slick-50. Here's several pages All About Oil justifying these conclusions.

http://www.calsci.com/motorcycleinfo/Consumables.html

It seems he highly recommends Shell Rotella T from Walmart.