I've got those on my 1600 Classic. I took them off the bike a couple of months back, cut out the crossover and welded the holes shut. They sound very distinctive now and you can actually here each cylinder firing instead of the muddled rumble.
A forum community dedicated to Kawasaki Motorcycle owners and enthusiasts. Come join the discussion about performance, modifications, troubleshooting, maintenance, off-road, touring, street bikes, and more!