I took a slow speed class yesterday. During the ride as slow as you can for 24 feet target 24 seconds test, I would occasionally hear a really loud sloshing sound coming from under the engine. It seemed only to happen if I was slow speed riding with the engine above 4500 RPM w/ clutch partially engaged. I don't normally hear that sound but I would normally be going faster with earplugs in and in gear. It was very distinct. I'm running 20w50 and I think it was just the oil going crazy. Wet clutch not fully engaged with high RPM = sloshing oil?