Marzocchi Bomber Z1 Suspension Fork - 27.5" 160 mm 15QR x 110 44mm Offset RAIL Sweep-Adjust Shiny BLKMarzocchi Bomber Z1 Suspension Fork 27. 5" 160 mm 15QR x 110 44mm Offset RAIL Sweep Adjust Shiny Black. The redesigned Bomber Z1 gives even more riders access to this celebrated Marzocchi workhorse. A 36mm chassis provides stiffness where it matters and an updated Rail damper allows silky smooth travel and enhanced traction for when things get rowdy. Forget fiddling with settings at the top of the enduro course this is about pointing your bike down