SiSl2 with OPI SpiderRing
As beautiful as the cranks are, the most eye-catching feature of the cranks is the OPI SpiderRing. Inspired by auto racing wheels, the 10-arm spider and both chainrings are 3D forged and machined from a single block of aluminum. This one-piece design saves weight and reduces chainring deflection for crisper, more precise shifts. The SpiderRing is available in both 53/39t and 50/34t options and is retrofittable to all HollowGram cranks.
HollowGram Si: Our patented OPI 3D forging process enables us to build hollow, seamless crankarms that are not only extremely light but also incredibly strong and stiff. In fact, they are the stiffest, strongest crankarms we've ever made. As light as the first-generation HollowGram cranks and completely compatible with every HollowGram spider and chainring set-up, the Si brings HollowGram performance to more price points than ever.
Si crank with 50/34t