on our local track, @ mallala race way (look it up if you really want) its surprising how well a TRX goes.. Its a short track thats fairly tight.. It also has one of the hardest braking corners on any race track in australia, and i THINK the southern hemisphere. Its a 220km bent straight, (locals call it "the kink) and the northern exit (turn 4) is ~30km/h depending on how brave you are.. This is where the TRX shines the best over MANY bikes.. engine brake ability plus being able to pull outta that corner with low revs in 1st gear.
Many bigger sports bikes struggle SO much with that. Its just fun to drag your ass outta a corner from there on the outside of a 600cc track bike.. funny as hell. Also, you get the hole shot to the inside of the sweeper left, so you get a good advantage there
FYI: get a 850cc, sleeve / bore to 900cc. you can stroke it to 916 comfortably without interfering with anything. Obviously you need to shim your barrels up a touch, etc.. Personally i wouldnt do it mainly cos of the oil holes, they WONT be in the middle, they will be offset, and i dont know how that will effect things.. And im not prepared to find out.
Car cranks CAN do this, as they grind out a little valley for the oil to work in, but they dont rev as much as a bike.. either way.