I am about to build a camping trailer to pull behind my 08 FLHT and have been seeing a bunch of trailers with what looks like a very long toung so is that for a reason?

 

Just a guess that it would lower the downward weight on the trailer hitch and bike.

 

It has to do with handling. The trailer doesnt respond as rapidly with a longer tongue. What ever the width of the trailer wheel base is, you want the length of the tongue to be same length plus 50% more at a minimum. Some guys like it 2 to 1 in length

So as a example, your trailer wheel base is 48" wide your tongue length from the front of the trailer frame would be 72" in length.

 

That now makes sinces.