I have a 7X16 Haulmark enclosed cargo trailer and have comfortably hauled 4 harleys, a dresser, two nighttrains and a FXST. Plus a butt load of gear for five or six riders. 7' wide trailer will let you put two bikes of any size side by side with no problem.

 

7x12 minimum. Works for me.

I got a 7x12 because I wanted to take up the least amount of parking space and also wanted tandem axles. A 7x14 or larger would make it even easier.

 

I tend to agree with others here. If you're buying new I'd go for at least a 7x12 and possibly even look into surge brakes as well. Your trailer dealer or others who have trailered alot could give you a better idea on braking systems or if they're even neccessary.

 

I got a 7x12 Haulmark Lo Hauler and 2 bikes with room for gear is no problem.Torsion, tandem axle is the only way to go.Real smooth ride and tracks like it's on a rail.

 

Just ran across this yesterday, dosen't say what the dimensions are but it looks like and good deal. http://oklahomacity.craigslist.org/mcy/2229405106.html