Spank Spike Race Vibrocore Bars 800mm Wide 50mm Rise 31.8mm Clamp Black. Spike Race Vibrocore HandlebarVibrocore is a low-density low weight core that reduces frequency amplitude and duration of chatter from the trail 7-Series alloy with micro-grain refinement during the drawing and extrusion process for a strong and light weight bar Dual Extreme Gradual taper technology (XGT) spreads the load out over a greater area of the bar to minimize breaks and bends TECH SPECS Color Black Rise 50 Material Aluminum Upsweep 4 Defined Color Black Back Sweep (deg) 8 Weight 360 Bar Clamp Diameter (mm) 31.8 Width 800