To add to my earlier post a bit-
Re-mapping is a good idea. The relative lack of o2 compared to sea level means you are now running richer. Assuming the bike was properly tuned in the first place, the fuel curve should be adjusted for this lack of o2.
This will not make it like it was at sea level, as the o2 level in the air simply isn't the same. There is no way to add more o2 to the air in your area.
You aren't running richer... the amount of fuel that is put into the bike is mostly based on the value read by the MAP (manifold absolute pressure
The reason there is less o2 around is because you are at a higher altitude... but o2 still makes up 20.9% of the atmosphere up there, its just at a lower pressure
meaning less air and subsequently less o2 per unit volume.
Given that the bikes manifold pressure will drop by a proportional amount to the drop in atmospheric pressure its is readily apparent that the bike's MAP sensor will tell the ecu of this fact and the mixture will be adjusted accordingly. Ergo: yes less o2, no you won't run rich.
As for correcting it, yes there is a way to do it: Free up the intake so that it flows more air into it... then get a p/c or bazzaz to correct the a/f ratio.
And before someone asks me why you would need one given that an increase in air getting into the bike should cause an increase in pressure, you would be right to an extent but its not the pressure that changes a whole heap, its the flow rate of the system... meaning more air in the front, more air in the cylinder and provided the latter offsets the former the pressure will remain the same(ish).