Unlikely; lighter rotational components should put less energy into the system, decreasing vibration.
The bars form a mechanical resonant system, vibrating at a particular fixed frequency. If this frequency is within the of the characteristic frequency spectrum of the motorcycle, the bars will vibrate.
Bar end weights work in two ways. First, they move the resonant frequency to a lower pitch, hopefully avoiding the frequency spectrum of the bike. Second, weight added to the ends of the bars increases their inertia making them less willing to vibrate back and forth, preferring to stay still.