It's more than about the best lock - think the system through.
Think like the bad guy - how would you steal? Think engine lock,
s/s cable (or chain),
dock lock - the bigger and more obvious, the
more likely it will detour the bad guy.
Think how you are going to use it? - On the dink? At the dinghy dock?
On the the ship's transom? In a locker? During off season
storage?
1. There are excellent all s/s locking devices on the market. Spend the money.
2. Use a high quality
stainless steel cable (not the plastic covered lifeline type
which sometimes has more plastic than stainless) Test cut it - if you can cut
it with your bolt cutters, so can the bad guy.
Chain, especially s/s chain, could be a good alternative to cable.
Test cut the chain. It's inexpensive, compared to the loss of dink and
motor, not to mention the agro.
3. Pass it through a transom lifting ring, the tank and anything else you don't
want to lose. Then the bow eye.
4. Use a high quality lock on the dock end - combination locks
work well, but
difficult to see at night... I prefer a key.
5. *** the strongest part of any system is it's weakest link ***
6. And folks .....
Lift it. Lock it. Or lose it....