Looking for specifically the 350lb tongue weight so I can use a hitch mounted small motorcycle carrier.

Total will fall under 350lbs - but above 200lbs which is a Class I hitch.

Any premade ones or can it be done custom?

 

I suspect it's theoretically possible, in the sense that a class II hitch could be built that would safely attach to the Fit. It would definitely have to be a custom design and fabrication, as nobody makes one ready-made. (I don't really blame them, either; towing a 3500 pound trailer with a Fit at highway speeds is not at all a safe proposition. I realize that's not your intent, but that's why many people might want a class II hitch.) You would probably need to do some upgrades to the rear suspension setup, as well; stronger springs or air shocks at least.

Bear in mind that a hitch-mounted cargo or bike carrier imposes a rather different load on the hitch than a trailer of the same tongue weight. The downward force may be the same, but the torque on the hitch is greater than with a trailer because the lever arm is longer. Also note that hitches for the Fit are pretty close to the ground; any sagging or bouncing could possibly endanger the carrier and its cargo. I've seen hitch-mounted cargo carriers on much larger and higher vehicles that end up dangerously close to the road surface (I assume at least partly because they were overloaded or because the hitch or mounting were in poor shape), and needless to say I preferred not to stay too close to said vehicles as I drove along.

All in all, I think a trailer for hauling the bike would end up being more practical, even if somewhat less convenient.

 

I'm not one to worry much about published weight and towing ratings on trailer hitches. I tow a 9500 pound trailer with a diesel tractor on it with my Colorado. BUT, I feel 350 pound tongue weight is a bit too much for a Honda Fit. I'm not recommending it but they do make adapters to allow the 2" drawbars to fit into the smaller class 1 receiver.

Hitch Adapter - 2" Adapter for 1-1/4" Hitches

I suggest looking for a small trailer that is towable with a class I hitch.

 

I want to put a Hammock on the back of my Honda Fit. I saw this add on https://gearjunkie.com/mclean-metalw...unt-hitch-tire and it would be great for me or the kids on the soccer games on weekends! I am wondering if finding a class 2 hitch for the fit or getting an adapter for a class one would work. I mean even if is 250 to 300 pounds I think it would work for a static load? Please correct me if I am wrong, do not know much about hitchs.

I found this post but the want to carry 350 pounds while the car is in movement and got me thinking that is possible what I want to do.

 

have you seen this one?

https://torkliftcentral.com/2009-201...t-ecohitch?v=4