COOK BROS. "E" CRANK ARM SET
The Cook Bros. "E" series cranks are more traditional in their styling. They are machined from 7075-T6 billet aluminum. Unlike the other Cooks arm sets these have a rectangular cross section, not round, and the E cranks use a replaceable, user installed spider. At the pedal spindle, the arm is 27.83mm, it reduces above the pedal to 18.5mm. On the left arm, at the B/B spindle area widens to 37.5mm. The arms are 14.14mm thick at the pedal spindle and thicken to 26.4mm at the B/B spindle. The right arm has five round posts protruding from the back of the arm. These five posts are drilled and tapped for the inner fixing bolts to anchor in. The spider with the outer fixing bolt pattern drilled into it also slides over these five posts. Custom aluminum spacers used with the inner fixing bolts tighten down over the machined plate aluminum spider. The right arm has four stubby extensions that the posts are fastened to. The extensions lie perfectly over the spider. The posts incidentally are positioned so that only a 58mm bolt center diameter can be used for the inner chainring. There are three choices of Bolt center diameter for the spider, either a 94mm BCD or a 110mm BCD or a 130mm BCD. At the moment, the arms are made only in a 175mm length, Cooks believes that they may introduce a 181mm version in 1995. The arms come anodized in Blue, Black, Grey, Lavender or Silver. The standard spider with the 110mm BCD weighs 47 grams, the 94mm spider weighs 34.5 grams. The spiders are available in the same colors. We found the arms weighed 396.5 grams, and had a Bike- Pro Q measurement of 162mm. The inner steel bolts and aluminum spacers weighed 38.5 grams. The E crank set comes as right arm, left arm, spider, five steel inner fixing and the five custom aluminum spacers that hold the inner chainring and spider in place. Chainrings, the outer fixing bolt set, crank bolts, crank arm dust caps and will need to be purchased separately. Specify crank arm color, spider BCD pattern and spider color.