[frosty]

Gentlemen, Please accept some wisdom from someone who has worked in engine oils for an oil company for over 25 years. When a manufacturer quotes a specificaion, it will be the minimum required not the optimum. Some places n the world you cannot get oils THIS good! We all know how expensive it is to repair and service our engines so surely a little investment will act as an insurance. Buy the best that you can. The only problem is spotting ther best. Forget Sponsorhip LOGOs as that just confirms who gave the team some money. It's no guarantee of the oil used in the bike. Firstly pick a viscosity. I would use nothing less than 15w50 as the viscosity will be marginal a high temperatures. It's the film thickness at 150 degrees which is critical. A cheap oil will also break down (shear) and that fine film will become metal to metal contact at high temperatures. Result is tell tale shards in the filter strainer. My 900SSie has done 25Kmiles and I have never seen debris in the filter! Only use fully synthetic as these stand 150.c plus without degradation. Degradation is spotted by lacquer or brown deposits in the engine. This is the oil oxidising. Another enemy of our bikes is oil shear. What oil do I use. Mobil 1 Racing 4T (Halfords). Oh yes, I do use the bike! All the miles have been European trips and ride schools on most tracks and the ring (several times) with no mechanical failures (wheres the wood!) ps. Harley love this oil too.