I helped a friend outfit his new 2016 Two with a hitch and cycle carrier. We installed a Curt hitch (1 hour, 2 beers). Modified a Harbor Freight hitch carrier by attaching a 1-1/4 inch to 2-inch receiver adapter after shortening the main tube by 11 inches (four inches longer than the adapter). I decided to post after his vanity plate came in. With the bike loaded the car sits 3/4-inch lower in the back, and approximately 3/8 inch higher in the front. The bike is a Grom (225 pounds). Headlights do need to be aimed -- he gets flashed more often. No noticeable effect on handling. The mileage tax is about 5 mpg. I don't think I would add more than 1 passenger. Of course it totally screws up the usefulness of the backup cam. The rack is nice (only $90 on sale with 25% off coupon, plus $9.99 for the adapter, also on sale.). There is a nice pinch setup for the front wheel -- the bike will not fall out of it. He also relocated the plate. I think it needs lights -- the rear fender obscures the right side signals a bit. With a fender eliminator for the bike, lights wouldn't be necessary. The rack does wobble a bit, but nothing severe. I have suggested reducing its width as it is about the width of the reflectors too wide. It does not exceed the width of the car (mirrors), so it is legal in California.
Keep an eye on the frame where the hitch mounts, you are exceeding the tongue rating and putting a lot of stress on the frame/bolts. I use a cargo carrier and will be adding more support to reduce the stress where the hitch mounts. It really needs at least 3 mounting points.
Not sure where the additional support would be placed. The only idea I could think of knowing the configuration of the Curt hitch we installed on the Gen 4 would be to use a "J" bolt to support the cross tube through to the storage area with a plate or bar inside the cabin to spread the load. That wouldn't help much with the rotational stress. As we installed the hitch, I was pretty satisfied with the structure of the car as the hitch bolt up points are at the end of boxed "beams." The box configuration is a pretty strong cross section. Also, although I don't know the actual values used in this design, it is not uncommon for engineers to build in 2.5 times the rated load for such connections.
That's an interesting hitch design. It looks better than the type I'm use to such as for my 04 Prius which mounts horizontally under the frame rails.
Do you have any update? Did it affect anything else in the long run? Tire wear, damage to the shocks? Anything ...? Would like to try the same with a 2012. Did you friend ever mention if it was all worth it? Is s(he) still happy with it?
I echo the comment about keeping an eye on the hitch, or reinforcing it. i have a Curt hitch on my 2017 Prius, and Curt specifically said for any loads on the hitch like a bike rack, you should buy their strap that goes from the rack to the top of the hatchback to absorb some of the bending loads. Of course a motorcycle is way more than a bike rack, hence my comment.
