It has been a while since college physics but you have less angular_momentum. The vector points out from the axle and magnitude is based on velocity and weight. So if the tire is 1/2 the weight you have 1/2 the stability. Conservation of angular momentum is what lets a top spin.
I misread. I thought you just changed tires on the same bike. Bike geometry will be the biggest factor. Head tube angle is a big factor. Tire and rim weight is also a factor.