from old Rallye years back in Europe... the Finns were taking their Winter Hakkapaelittas Rallye tires into the sauna before they tried to mount them on the car rims.
A little bit the same with the stiff Schwalbe Winter tires for bikes... The rubber compound is different than the regular tires and they are a little stiff to mount.. even in the 20 inch version which we sell frequently.


I love those tires... just make sure on black ice, that when you put your foot down that u be extra extra careful ... ( don't ask )