Recently I purchased an ascend DC156 canoe. As far as being on the water goes, I love this thing. It is incredibly stable and has very comfortable swivel seats. Trying to car top the canoe changes my perspective quite a bit however. The thing weighs over 100 lbs, and the main problem is that the seats don’t fold completely flat and are partially above the gunnel. When car topping, I have to position the canoe just right so that the back seat is behind my rear window, which leaves a lot of boat sticking off the back of my car. It would be much simpler to have the seats come off the canoe, which would help me position it better as well as reduce some of the weight. Are there any sort of quick release pins or even quick release swivels (with stops) that could make getting the seats on and off easier? Also, any tips on car topping a (very) heavy canoe are greatly appreciated.
Can’t help with the seats, but…
... I can with the other stuff.
First, how far off-center toward the rear is the boat? If the center of the boat is about two feet behind the centerpoint between the rack bars, I wouldn't call that excessive, and doing so actually improves the way the boat handles crosswinds and turbulence in the air from other traffic (especially big trucks). If you are trying to center the boat over your whole car, that's generally a mistake because it amplifies problems with wind and traffic turbulence, so shifting the boat rearward away from *that* position is definitely a good thing. I usually position a canoe so the center of the canoe is about 1.0 to 1.5 feet behind the center of the roof rack.
As far as loading goes, the easiest thing is to have the rear bar close enough to the rear of the car that you can lift one end onto that bar, then simply lift the other end and slide the boat onto the rack. The next-easiest thing is to use a commercially available load-assist bar, which extends off the end of one of the crossbars. With that setup, you put one end on the load-assist bar, then lift the other end and move it sideways onto the rack, followed by shifting the first end sideways from the load-assist bar to the main rack. A third method is to attach a longitudinal bar on each side of the car, connecting the ends of the front and rear cross bars. With this setup, you slide the boat on from one side and pivot it around to the normal carrying position once it's up on the rack.
All three of these methods require an aftermarket rack (or a well-deigned homemade rack), which is usually best for other reasons too. You didn't say what kind of rack you are using, but if you have a factory rack on the roof, any of the makers of good racks will have adapters to attach their cross bars to the existing rack. The slightly higher height of aftermarket cross bars might be enough to solve your seat issues too, though as I mentioned above, my suspicion is that you are trying to put the boat too far forward on the rack as it is (you should center the boat on the rack, not the whole car, and even a little behind-center, relative to the rack, is fine).
Get a lightweight canoe trailer
I wouldn’t want a 100+ pound canoe, but if I had one, I wouldn’t try cartopping it unless I was still 22 years old.
Even lifting just one end for rear- or side-slide loading would be a 50+ pound lift. Plus, the protruding seats interfere with sliding from the side or rear onto the bars.
I’d consider a lightweight canoe trailer, of which there a few brands. With these, you can also wheel the beast boat from your vehicle to and back from the water if there is a boat ramp or smooth put-in approach. And you can leave the boat stored on the trailer at home.
I would haul it with a trailer.