Do you find your motorcycle has less power at high altitude?

Everyone has the problem. When you go to higher altitudes, your bike is going to run richer because the air is thinner. Thats the whole purpose of rejetting the carb(s), for the proper air fuel mixture. The only problem is that if you dont live around that altitude, then rejetting would be a waste of time if you are returning to lower altitude levels (where you live). Fuel injected bikes have sensors that can compensate for the change automatically, and the ECU gives the injectors the proper fuel mix automatically. Thats one of the best benefits of fuel injection over carbs, the bike does it for you.

edit: CV carbs have to be rejetted for altitude changes too Adam, the diaphragm compensates, but if the jetting is too rich, its gonna run crappy at altitude.

High Altitude Bikes

Jon is right BUT: your bike has a C.V. [constant velocity] carb,it has a rubber manifold that raises and lowers the jet needle and therefore does compensate for altitude change.

of course it does, engines need oxygen to work, at higher altitude there is less oxygen in the air, therefore less energy can be produced from the fuel.