fuel for motorcycles at altitude

[eyepecka]

what happens to a bikes performance at higher than usual altitudes ? is it healthier for the engine to have lower octane fuel running through it or higher, when up in the mountains ?

[Toureman]

Changing the fuel will not make any difference, it will loose power because there is less oxygen getting into the engine at high altitude..

[dilligaf]

I think the normal fuel you use is ok. There used to be a problem several years ago when carburettors did not function efficiently at high altitudes. Now a days with fuel injection systems the problem has been resolved.

[deloupie]

petrol mixture will be slightly leaner ( or is it richer ?) at altitude so it may run a little rough when idling and at low revs.