What are the safety concerns of a high vs a low mount trailer hitch?

Question

When you google for images of (canoe & bike) you find two basic solutions to towing a canoe with a bike.

1. A traditional axle mounted tralier is modified to have a tongue long enough to load/support the canoe/kayak on the trailer.

2. A seat post or carrier mounted pole connects to the front of the boat, the boat servers as the "trailer frame" with a canoe dolly (wheels that attach to the boat for moving by hand) for wheels.

Solution 2 offers the advantage of less material and more a portable trailering solution. With this solution the bike and trailer easily fit in most canoes, so you have a fully amphibious combination.

Is there any significant safety considerations when towing with a bike from a higher or a lower tow connection on the bike?

Answer 1

The higher the hitch the easier it is for the trailer to push the bike sideways or lift the rear wheel of the bike under braking.

With the high hitch you can generally only do one of turning and braking at a time. So if there's a problem and you need to swerve and brake to avoid it, you will end up lying on the road with a canoe on top of you. And a bicycle. And a trailer. And they will all still be moving.

The solution is to disconnect the rear brake of the bicycle and use that lever to operate the the trailer brake, but few people do that because it's not trivial and in practice it's not really necessary. Most people find that the "tow my canoe" rig is big, heavy and unwieldly, so they only actually tow for short distances on flat ground. That makes riding slowly and carefully quite practical, and often they can choose quiet streets as well.

One other option is a three or four wheel trailer which you could do as a rear dolly and a front, pivoting pair of wheels. Handling will be better than a central dolly if you can work out how to attach the front solidly to the canoe. Or have a spine to the trailer.

This question is much more important for touring trailers and work trailers, where the distances covered are greater and there are fewer opportunities to avoid bad roads. That means the consequences of a crash are more severe as well. But at the point where you're building a trailer with brakes and suspension (because there are 4 wheels) it becomes worthwhile modifying the towing vehicle as well. Most people start down that path and end up with with a trike as the load vehicle or the towing vehicle, or a quad bike. It's much simpler to build and ride a single vehicle than a trailer.

Answers like this Burning Man Trailer one deal with the general details of heavily loaded trailers. It's also worth mentioning Richard Guy Briggs and his canoe carrying tricycle

Answer 2

I now have about 100 miles (160 KM) towing my 17 foot canoe behind my bike all of it with the hitch mounted to the seat post. I have been averaging about 5 - 6 miles per hour for distances of up to 15 miles (24 KM) on mostly straight and level trails (rail to trail).

There have been occasional tight turns, and narrow areas. I do NOT have brakes on the trailer/canoe. The hitch location has not caused any significant issues. On one occasion, the canoe tipped over (pushed over by coming to close to a pole when I was learning) and the bike was not unmanageable during the event, I stopped, got off, tipped the canoe back on it's wheels, continued on my journey.

Because the rig is so long, I have to approach sharp corners slowly, so no real opportunity for side pressure there. On the occasionally down hill coast, I have used the bike brakes to keep speeds below about 10 miles per hour.

In my application; long load and relatively high (100 pounds / 45 KG) tow weight, without brakes, keeps the prudent speed below any point where the higher hitch point would be a concern.

While I can't speak to other scenarios (Mσᶎ has a fine answer), for a bike towing a canoe, the high hitch point has not been a concern.