Ruts in the corners definitely form differently on tracks with mostly 4 strokes. That was one of the biggest differences I noticed when I started racing again in '06 after 20 years off. When I raced as a teen in the early to mid '80's, there were never the 10-12" nearly vertical ruts in corners like there are now, the turns used to berm up more. 4$ts have so much more traction that even squids can pin it from the apex of the corner out, a 2st rider needs more skill and throttle control. Plus the 2st can cut & thrust to the inside and blast out, where 4$t riders can't.