Try the shoe covers that surgeons wear. You can buy them at almost any medical supply store & even some pharmecy's now. then simply take them off & wad them up & stuff them in your bag. Or take 2 pair, one for the going from your car to the pavement & one for the going from the pavement back you your car at the end of your ride. But only do this if there is a trash can handy to throw them away. If you only use one pair & if you do not have any room for a pair of wadded up medical shoe covers then you should rethink how much stuff you need to be carrying in your pack & bag.