Thanks to all who responded my question about tubes for my Speed. I found a
site that has most all sizes needed for trikes.
http://www.gaerlan.com/bikeparts/bike.html
I also found a site that a person has regarding adding things to his Catrike.
He has some pretty interesting ways of doing things.
http://www.virtualflint.com/bike/catrikemods.html
Still haven't heard from anyone who has ever changed to a bigger chain ring
though.
Mickey