- Joined
- Apr 7, 2009
- Messages
- 210
quote: Newer oils have reduced the amount of zinc, and can actually be harmful to old engines unless a zinc additive is combined with the oil. I believe 1000-1300ppm is the ideal range for zinc.
Mobil 1 V-Twin contains 1700 ppm Zn.
Mobil 1 Racing 4T 15W-50 contains 1200-1300 ppm Zn (an independent lab measured 1315 ppm)
quote: Viscosity retention is why synthetic oils can go up to 25,000 miles (40,000KM) in some applications. For 3000 miles or less between oil changes, the difference is negligible.
I don't think this is true. Mineral oil begins to degrade immediately. The tabel I referred to shows high viscosity retention losses after only 800 miles.
Mobil 1 V-Twin contains 1700 ppm Zn.
Mobil 1 Racing 4T 15W-50 contains 1200-1300 ppm Zn (an independent lab measured 1315 ppm)
quote: Viscosity retention is why synthetic oils can go up to 25,000 miles (40,000KM) in some applications. For 3000 miles or less between oil changes, the difference is negligible.
I don't think this is true. Mineral oil begins to degrade immediately. The tabel I referred to shows high viscosity retention losses after only 800 miles.