I'm talking vabout the 2 clamps that hold the bars down as you stated.. Are you referring the the steering stem? If you mean the steering stem (the long tube from the bar clamps to the first rods) than no you can't change the top. I think you are talking about an anti vibe steering stem ?? No u can't change it to an anti vibe stem, however you can custom make one using the bottom of the existing stem and welding on a new anti vibe top mount, or a cheap easy anti vibe stem is to pull off the plastic cap under the bar mounts, spray in some foam insulation like "great stuff" and it does actually work and asbsorbs some of the vibration..