Have read lots of information from you guys on this site about front tires, and just recently a little information about rear tires. However, I have never seen anything about changing rear tire and wheel sizes. I am having my 2006 Wing triked with CSC conversion. The standard rear tires are 205/60R 15 Sigma All-season mounted on 15 X 6.5 wheels. I want to change the look a little and go with 205/40R 17 Goodyear tires mounted on 17 X 7 wheels. The tire dealer I am dealing with says with the proper wheel, they will fit. My question is - has anyone else done a similar change, and if so what effect would the lower profile sidewalls of the 40 make on handling and performance? Your thoughts and comments would be much appreciated.