Not wishing to cast doubt on anyones abilities and, I can't talk as I've yet to change a tire on anything other than my bicycle. But the crafty chap did point out that you shouldn't need much strength to change any tire if you're changing it properly. The key seemed to be, once the bead was broken, to sit it in the well of the wheel therefore giving more slack to the opposite side of the tire so you could get it on or off. Oh, and lubrication was important too... soapy water or if you're in the field, shampoo etc.