If you look here
https://racetech.com/ProductSearch/1...%20S%20SA/2019
you will see, under **Front Products**, that the the standard/stock spring rate is 0.71kg/mm. Just below, "under Fork Springs & kits" is a link to a calculator where you can enter your weight and riding style, to calculate the correct springs for you. I agree with Bibio, avoid progressive springs for the reasons stated, plus, they are synonymous with excessive fork dive on initial front braking.