Mercury - 20W-50 Synthetic Blend Motorcycle Oil V-Twin 4-Stroke Series Synthetic Blend 8M0160549. Overview. Every rider knows that the bond between a V-twin engine and the open road is something you feel long before you hear it. There's a certain trust in that low, rolling rumble - the kind that tells you the engine is ready for heat, long miles, and whatever the ride turns into. When you run Mercury Marine part 8M0160549, that trust comes easier. You know the oil inside is doing more than just