Tire Questions for 1800s

New to this board, been reading for a while. Sounds like I would like to give this a try. I have a 2004 1800s
My question is conserning the tire height, not width. I would like to get a tire that is taller that stock. Wide is nice but I spend a lot of time at 75 mph or more and would like to help lower my rpms to get some more mileage.

I have read that I can put a 205/60/15 on the bike but that tire is about an 1 1/2" shorter than stock. I would like to know if any one has tried a taller tire? I have tried to see how much clearance there is between the tread and any fender bolts or braces, but have not had much success. I know that actual measurements of non mounted tires is diffucult to check. Tire height does change depending on rim width and tire pressure.

Thanks for all your help.

Gene Schafer

Welcome to the board

You can easily fit a 205/70/15 on your 1800S. Maybe have to turn some muffler mounting bolts around.
Your only other decision is whether you want to seal your rim or use a tube.

I can only speak for myself, but i used a 205/65-15 on my 1800S. I sealed my spokes with the 3M 5200 and have had no issues or leaks.