Hi Harley, I love the look of your bike. If the head is ported at 26mm, as far as I know there's no advantage putting a 30mm carb on. I would lean the plug and do a "plug chop" at full throttle and see what the colour is to find out if it's running lean. If it is you can go up a size on the main jet. If it's the correct colour or black, it doesn't need any more fuel. That's where I'd start.
