I have a Kromewerks hitch. Says 30 pounds tounge weight. I use a large fish scale to weigh it before hooking up. I'll adjust the cargo if nessessary. I have the Haul Master Tag-A-Long from Harbor Freight. It has a max capacity of 600 lbs. for pulling behind a car and I belive they say max 250 lbs. for pulling behind a motorcycle. I'll get all the specs and put it on here this weekend if I aint out riding. I weigh in at 200 lbs, the wife at 150 lbs and I have a '96 FLHTC.

 

I'm a little slow, but I catch on eventually! Guess havin the need for a tire had me wishing like mad!

 

From what i have read find your bikes GVWR then deduct the passangers and the weight of the trailer. What your left with is the amount you can saftly haul. What info I have found and what like others have stated no more then 10% tongue weight.