How about some more info on the Aussie racing gear? What is the wood, comparable to US hardwoods? Any pics of race chain for this stuff?
I'm the wrong person to answer, lumberjackau is the man, but haven't seen Will on for a bit so I'll have ago.
The timber varies, depending on what's native to the area but it'll be Eucs of some description
lumberjackau has a you-tube channel
http://www.youtube.com/user/aussieracesaw and they've used 'Bloodwood' (Janka hardness, 8.8kN) at a number of his state's shows. You'll find that whatever Eucs they use, generally it'll be harder than Black Locust (Janka 7.6) and often harder than Hedge (Janka 9.1) too and a lot of Eucs are very dense.
To give an idea of how tough it may be, if they use something like Grey Ironbark for the post rip (common fence post timber) it has a Janka hardness of 16.
Chains in the speed events are a closely guarded secret, but in the post rip it's generally Oregon 21LP (I was told 'Pixel' chain, which is the Husky name) with the top plate angle re-filed running 18" bars (+-2") driven by 3120's and 088/880's.
The post rip is an endurance event, so the saw needs a bit of a different setup to a cookie cutter and the chain needs to be pretty robust.
This is one of Wills vids of the Post Rip final at a big show that I've posted up a few times already.
<object width="480" height="385"><param name="movie" value="http://www.youtube.com/v/MM0KcjOMgr8?fs=1&hl=en_GB"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="http://www.youtube.com/v/MM0KcjOMgr8?fs=1&hl=en_GB" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="480" height="385"></embed></object>