[blockquote]Terrier said: I've not had very good luck with flags. They tend to come apart after just a short trip. I ran both U.S. and CSA Navy Jack. After 200 miles they were both retired.[/blockquote]
A standard cloth flag will tend to do that. Flags that are intended to be flown from a moving vehicle are normally a little tougher and made out of a synthetic blend like nylon. I have a CycleFish flag that a good friend had made for me and it has probably over 10,000 miles on it.
I do not put flags on my bike ... never have never will .