Ah right yes... I think the record is currently held by a Swede and is 1:33.__
There is little chance of any of us getting that good, I have a 1:39.800 and struggle to get any better.
The continental and world rankings are not times given by Nintendo to beat, they are times that real (incredibly good at Mario Kart) people have entered into the competition.
So the only other times you should take note of are any of your friends times, who are more likely around your skill level, either that or just tke part to better yourself.
Generally you need a reasonable start, but also you need to pick up an item box before you get into 1st place (prefereably when still in 5th/6th) if you get a mushroom/some mushrooms then you are in luck, so you can use that mushroom in whichever place benefits your driving style the most. and then pick up another item to use as protection against red shells for the remaining laps.
Even then of course you are subject to lightning bolts etc from the pack, but I haven't ever had more than 1 of each (blue shell, lightning, POW) in a single race.
