Tyres will also ware faster near the equator .... at least in OZ. The road surface is more abrasive up there .. probably due to the weather conditions (monsoonal rains, floods etc).
You should get at least 10,000 kms out of them. The fronts tend to ware faster on K models - more weight on the front tyre? Or geometry? What ever - I find that the front and rear tend to need replacing near the same milage.
Regards Frank Warner
motorcycles BMW R80 G/S 1981, BMW K11LT 1993, BMW K75 G/S