They might help a bit, sliders open the variator a little wider allowing higher top speed. Heavier will be lower RPM at any given point UNTIL the variator hits its maximum gear ratio.
You are correct. I installed 23 gram dr pulley sliders on my 2009 Xciting 250 in efforts to reduce cruising Rpm. (In hindsight, It actually needed a new belt) . My rpm's decreased at most speeds. Even with the new belt and the sliders, my rpm's at 70-71 mph are around 7500 . I think the variator maxis out around 6500-6800 rpm with the 23 g sliders. But at 65 mph the engine seems much more relaxed than before.
