Early LiS headset question

I'm running a TS1 230 and am getting enough vibration through the grips to make my hands "ring" when I stop after about 60 miles. In an attempt to counteract it, I'm looking at putting some heavy bar weights into the ends and also use foam grips. I'm waiting for the grips to arrive so don't want to cut the standard ones off yet.
Can someone tell me what the internal diameters are of the bars please so I can get the weights ordered.
many thanks.
Can someone tell me what the internal diameters are of the bars please so I can get the weights ordered.
many thanks.