HDK-0012 - IS 42/52 45x45 Drop-In headset kit

This IS42/IS52 integrated/drop-in headset fits bikes with head tubes with 42mm top IDs and 52mm bottom IDs, bearings with 45°/45° chamfers and tapered (1.125" x 1.5”) steerer forks. Includes 440C stainless steel upper and lower bearings, upper bearing cap, hidden bolt topcap preload adjuster, with 45° crown race and compression ring.

Enduro stainless headsets always feature top-quality 440C balls and races, dual-lip seals top and bottom, 90% fill with high-pressure waterproof grease, and are guaranteed for as long as you own the bike.

This headset features ACB 4545 1125 SS (also known as MR042, 870E, MR121, MR070, MR084, MR116, TH-870E, and MH-P08) with 30.5mm ID, 41.8mm OD, and a width of 6.5mm, and ACB 4545 150 SS (also known as HSS011, BAA0695K, TH-070, MR-128, and MH-P16) with 40mm ID, 52mm OD and a width of 7mm. Please note that both of these bearings differ in width from many of the standard bearings that they replace, though they stack to the same height when installed. If you need additional clearance, we also make spacers for both the upper (HD-120 included) and lower bearings (WA-45 1x150 available separately) to provide a little extra stack.