Vintage Campagnolo Record 51t 42T Chainring Set 144 BCD 51 Tooth Road Italy 80s. Vintage Campagnolo Record double chainring set for classic road and racing bikes. Tooth counts: 51T outer ring and 42T inner ring, stamped 51 and 42 as shown. Bolt circle diameter (BCD): 144 mm, 5-arm pattern for compatible Campagnolo road cranks. Silver aluminum construction with large cutouts and PATENT CAMPAGNOLO logo on the outer ring. Inner ring features Campagnolo C diamond logos near the bolt holes. Weight for the pair: 241 g on shop scale. Only the two pictured chainrings are included. Vintage Campagnolo Record 51/42T chainring set shows wear from prior drivetrain use. Tooth faces on both rings have visible chain wear, finish loss, and scattered dark spots and stain marks. Ring surfaces show numerous small scratches, scuffs, and light grime. Listing includes the two chainrings only; tools, scale, and measuring guides are not included.