Stihl and Husqvarna saws handle almost all the racing.
044,046, 066, 084 (most popular) 088, 090 for Stihl
just a few 090's today, they do come out for odd 090 class visually standard runs in QLD.
272,575,576,394,395 3120 (dominant in NSW, no quite so in QLD) for husky.
an odd other saw like the 2100 etc. but mainly the above saws compete the regular calendar events.
a couple of kart saws have been doing the rounds in Open Speed.