Several things. 1st, I've always hated crawling around under a dripping wet boat trying to get the transom saver connected to boat and trailer.
2nd - my biggie: most trailers I've seen have springs far too heavy for the load they're carrying. I "think" the average 14 - 16 ft tin boat will weigh around 500# with motor and fuel, etc., ready for the water. I know mine is in that ballpark. The springs on most trailers I've seen seem to be aimed at 2,000# boats (only exaggerating a bit here) and they bounce like crazy on rough roads. Many times I've watched in the rear view and cried a bit. On several trailers I've owned, I've removed a leaf and gotten a much better ride for my boat. Of course, you hafta leave enuf to properly support the whole thing. I've often thought of adding shocks to a boat trailer but haven't tried it. I'm very sure they'd make a big difference.
Get a 200# man to stand in the boat and bounce up and down while you watch the trailer springs. On many or most trailers, there'll be hardly any give at all. You "know" what that's going to do to your transom.
3rd has already been said - the bunk boards MUST extend beyond the transom to give proper support.
4th is what I do now with my 16 ft Starcraft Seafarer with 25 hp Johnson 2 smoke: I measured from rear oarlock on one side, around the back of the tilted motor to the oar lock on the other side - on mine, about <12 feet. Bought a 14 ft, 1,000# rated ratchet strap and hook it up when prepping to tow. Just drop the hooks into the oar locks. Crank the ratchet strap to where it lifts the motor completely off its' stops and all flexing is eliminated. It only takes a minute to connect or dis-connect and it does the job beautifully.
(my biggest fear on that is if I'm in a market or café, someone is going to see that perty blue strap and steal it.
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