Friction is the key, so some mild abrasive that simulates the same thing as your thighs are doing - a used scouring pad? Tbh I would just plump up for a nice new white selle cheapie, got to be worth a tenner for the hassle? Or offer it up and put a wanted ad on the forum. The shape looks similar to an Arione if you wanted to splash the cash, they are always coming up on ebay.
Friction is the key, so some mild abrasive that simulates the same thing as your thighs are doing - a used scouring pad? Tbh I would just plump up for a nice new white selle cheapie, got to be worth a tenner for the hassle? Or offer it up and put a wanted ad on the forum. The shape looks similar to an Arione if you wanted to splash the cash, they are always coming up on ebay.