Wet Sump vs Dry Sump

[Randy]

I was reading some of the specs on a BMW 1150 Rockster, it stated that it used a Dry Sump for oil lubrication. What is the difference between a wet sump and a dry sump? Are there any advantages to either variety?

[BuzZz]

A wet-sump engine carries it's oil in the cases all the time. A dry-sump lump carries the oil in a seperate oil tank and uses 2 oil pumps... one to feed pressurized oil to the crank, cam, pistons, ect., and one pump (scavanger pump) to suck the oil out of the cases back into the oil tank after it lubricates the moving parts. The C/G tends to be lower as there is no oil pan to worry about.

A dry-sump motor can be made to slightly smaller outside dimentions as you don't need 3-4 liters of oil storge capacity. So you can have a larger reservoir of oil if you find a place to put the larger tank on the bike. They also don't lose any power to turning gears, ect while submerged in oil, but that amount is very, very small.

Either system works as well as the other..... there's more lines, pumps, and things to cause potential problems with on a dry-sump, I spose, but that's about it.