Found a handlebar anti-vibration kit on e-bay. I did a search here and found no info on it. Going to their website I found that it was a new product. The kit also raises the handlebars 1". 07' bone stock motor. 9,000 miles. So far I have filled the handlebar with lead shot and added bar ends. they did a little but not enough. I recently added mirror vibration dampners and those helped more than the previous cures, but still not even close to good enough. I decided I'd be the test bunny for this product. I was going to add handlebar risers anyway, so what the heck. Got the product today and got it installed. It has adjusting shims provided. I used one per bolt(four bolts). Wow. I said that several times before I got out on the highway. Wow. This really works. Really. Below 60mph it's not just tolerable, but comfortable. You can feel it, but not enough is transfered to even mention. Above 60 it starts growing until at 75 it's pronounced but still noticably less than before. This was money well spent. http://www.gripnripracing.com/product_info.php?cPath=41_48&products_id=126
Don't forget to "tune" the mounts. Changing the preload on urethane mounts will change their vibration reduction characteristics. You should be able to get that cruising speed vibes cut down (while making some other speed a little bit worse). And don't forget LOCKTITE!!!! the bushings can let the bolts back out easy.
Hmm my bone stock 98, well with the carb unplugged and the do done, is very smooth. Nothing at 3000 and very little at 4000 then increasing slowly. This on a 24,000 km bike. Maybe your balancer aint where it should be. My stock bars are perfect for my 6' spider type body. Standing is perfect and I am not changing a thing there. Now the rest .... cue maniacal laughter.