A 190 tire 'Should' be mounted to a 6" rim. If you mount it to a 5.5" rim it changes the contour of the tire and it effects the handling characteristics. It's done all the time but your bike will handle better with the tire mounted to the correct rim width. Triumph went to a 5.5" rim and the 180 tire on most of it's sport bikes for a reason, better handling. I have the Avon Azaro 45/46 (Sport Touring) combination on my bike and it may be just what you are looking for. Most people (myself included) mistake the 180 Azaro for a 190. They run wide. I also loved the way they transformed the handling of my bike. Much better turn in and steering response. They also make a 'Sport' version in the Azaro 49/50. I use my bike for getting to work so I opted for the model that will give me more life. I now have 4k on them and they show no real signs of wear yet! They handle great, (IMHO) they give great mileage and they look FAT, might be just what you need.
Here's a link to a package deal on them. They had the 49/50 package when I was looking. (Just my luck)
Avon 45/46 Package Deal
[ This message was edited by: Stlakid on 2005-04-19 14:52 ]