HollowGram SiSL2: Simply the lightest, stiffest, most incredible cranks to ever be bolted onto a mountain bike, the HollowGram SiSL2 represents the latest evolution of the crank that started the BB30 revolution. These hollow cranks are created by bonding together two machined, heat-treated clamshell halves with a super-strong anaerobic bonding agent. The result is a crank light and stiff enough for our top road race machines but tough enough for a life on the trails, as the full throttle performance of our CFR and Sho-Air Pro XC teams shows. Since the spider is interchangeable, HollowGram cranks have many different double and single-ring chainring options, including XX1.
SiSl2 with XX1 chainring
HollowGram Si: Our patented OPI 3D forging process enables us to build hollow, seamless crank arms 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 with 38/24t chainrings