The Yucatan knot was first developed in the sport fishing waters off Cancun and Isla Mujeres. It is generally considered to be a good knot for connecting doubled main lines to heavy leaders.
Some say that the Yucatan is not suited for light leaders, however, this is probably because the quality/brand of the two components (mainline and leader) will strongly influence the integrity of the knot. For example, with this knot the leader must form around the braid and on some hard leaders this may not be possible. Likewise, the Yucatan knot must be formed using an unbroken (full loop intact) double, such as can be formed using a bimini twist (or spider hitch).
One philosophy behind the Yucatan’s popularity is that if it is tied to connect 50lb braid to 80lb leader, such as you might when reef fishing, then the 50lb braid might test at 65lb breaking strain which is then doubled to give a potential 130lb limit; concurrently the 80lb rated leader is unlikely to break at over 100lb breaking strain. Throw in a few nicks in the leader and you’ll pop the so-called 80lb leader before you blow apart the 130lb breaking strain double.
The finished knot is compact and very strong. It will pass through rod guides easily, making it suitable for repetitive casting techniques. The Yucatan is an excellent knot for joining heavy mono-type leaders to superbraid mainlines.
To Tie the Yucatan:
Make a short double line using a bimini twist to form the double. Lay the double alongside the leader (parallel to but opposite in direction). An overlap of 20cm is a good measure.
Wrap the super braid double line 12-15 times around the leader, or as many times as you can for mono to leader connections probably around 6 turns. Knots that require multiple turns of line must lie and draw up neatly, without line overlapping.
Now bend the tag end of the leader back on itself and feed it through the loop end of the double line.
Lubricate with saliva and carefully pull the knot tight. Pull the doubled line and the leader in opposite directions to tighten knot. Note that although the wraps were made with the doubled line, when the knot is pulled tight the leader will wrap onto the doubled line. Trim the tag end of the leader close to the knot.Reads: 6606