Quote:
Originally Posted by Javi Cooper
But that's actually the reasoning behind the DOF; the bearing, even though it's submerged in oil at rest, is NOT submerged in oil at all when the engine is running, contrary to popular belief. Here's a visual explanation from Pedro:
https://www.youtube.com/watch?v=qj06dqBk0to |
Yeah, I came across this video. Still, I don`t think it justifies the need for DOF. The IMS is submerged almost all the way to the top of the shaft when your level is at the max sign, and is submerged around half way up when it`s at the min level. So, the inner ring (that is fixed) is always submerged in oil that will carry excessive amount of oil onto the balls and the outer ring. Centrifugal force has nothing to do with this because the inner ring is not spinning. Ball bearings do not require DOF. There are motorcycle engines with ball bearings operating at much higher rpm and temperature that an IMSB and they are totally fine with submerged or splashed oil lubrication or even oil mist in 2-stroke engines. But you don`t have to go that far, look at the ball bearings in your transmission, they are lubricated by splashing oil, and they don`t fall apart, even if the input shaft is spinning at much higher rpm than the IMSB.