When we purchased our TI we got the Hobie Trailex trailer for it, and it works great for long-distance hauls - but now that we're keeping our TI in south Florida, we've found that many great kayak launch sites are not trailer-friendly. We've also been considering getting a motorhome when we retire, in which case the TI could be car-topped on a "toad" vehicle, but surely couldn't be dragged behind it in a compound-trailer configuration.
So here is our approach to car-topping, for the benefit of anyone else who may be considering it. The assumption is that you have a vehicle with a 2" trailer hitch receiver and a roof rack with crossbars (in our case a 2004 Jeep Grand Cherokee).
Materials needed:1 pair of Hobie TI cradles
1 Extend-A-Truck hitch-mounted support bar
1 pair of Yakima bow & stern tie-downs
1 48" piece of 2x4 lumber
6' of foam 1" pipe insulation
4 ratcheting tie-down straps
bag of 24" heavy-duty cable ties
6 1/4" SS flat washers
3 1/4"x1.5" SS lag screws
2 1/4"x1.5" SS bolts & lock nuts
1 1/4"x3.5" SS bolt & lock nut
electrical tape
Optional:2 locking hitch receiver pins
1 alarmed motorcycle cable lock
2 magnetic taillights
Scotchlite reflective tape
The Extend-A-Truck unit mounts into any 2" hitch receiver. Simply bolt a Hobie TI cradle to top of the 48"-wide crossbar. Two of the ratchet straps are used to stabilize the upright, the reflective tape is optional.
For the front unit, position both roof rack cross bars as far forward as possible and adjacent to each other; shape the ends of the 2x4 to fit, as needed (and possibly cut shorter than 48", depending on your vehicle); lag screw the 2nd Hobie cradle to the 2x4; pad the inner edges of the roof rack crossbars with the pipe insulation and secure with electrical tape [great stuff - no residue]; secure the 2x4 between the roof rack crossbars with 2 cable ties [new ones will be required for each installation -- cost ~ $1].
To get the TI onto the roof, position the hull (with the mast secured to it) so the bow is alongside the rear cradle and overlapped such that, when lifted, it can sit on the cradle, and place a rubber mat under the stern to protect it and keep it from sliding [easy with 2 people; requires the use of some sort of cart if alone (or with a small 2nd person) -- we use the Hobie Heavy Duty cart inserted into the rear scuppers]. Then lift the stern of the TI, and slide it forward into position such that the rear scuppers are just behind the rear cradle; install the akas & amas; secure the assembled craft with the 2 remaining ratcheting tie-downs [one to the loops at the ends of the Extend-A-Truck crossbar, the other to the roof rack side bars just behind the front cradle] and the Yakima bow & stern tie-downs.
The Yakima straps will prevent the TI from shifting rearward. To preclude any forward shifting under hard braking, tie it to the Extend-A-Truck upright via the rear scuppers, or [optional for greater security while parked] run an alarmed motorcycle cable lock through the scuppers and around the upright. Security can also be enhanced by installing the Extend-A-Truck unit using two locking receiver pins instead of the supplied items.
Now you are ready to roll
We've tested our setup at 70mph on the Florida Turnpike, and have found it to be very stable, with a fuel economy penalty of only about 2 mpg.
One final suggestion: if you will be traveling at night, the visibility of your load can be increased by placing a pair of magnetic taillights atop the metal crossbar and underneath the rear cradle -- no way you won't be seen
Merry Christmas to all, and to all, a good sail.