Hi Benji, if you can post a picture, that'll be the quickest way to tell you. All sandcast and "K0" bikes have same forks, as pictured on every bike pictured in website. Visually, from outside, the lower (aluminum) slider on K1 is tapered in the seal area; sandcast/K0 is "stepped." The K1 requires different seal size and if i recall correctly, the internals are different from sandcast/K0.