J120 front copy

J/120 Asym Spinnaker Trim



  • Takedown line is tied to the tack and led back to the forward hatch.
  •  Lazy sheet is tied to the clew and led aft to the weather side over the pole end and over the takedown line. It is important to lead this line behind the asymmetric ~ tack and ahead of the headstay.
  • Place a mark on the asymmetric tack line and on the tack line cleat to mark the position of the pole at full extension. A big time saver!
  • Add a 1.5 meter Spectra pennant to the clew of the asymmetric to allow it to pass smoothly across the headstay.


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North has developed two asymmetric sails, the AP Reacher, and Max Runner. Together, they cover a wide wind range, with cloth matched to the wind speed.


The AP Reacher (right) is especially well suited for point-to-point racing, with the area at 120 M2 constructed in .85 poly. Fatal Attraction is flying the reacher with the AWA (apparent wind angle) at 500 and good heel angle. The sheet is led through the aft spreacher block. To sail at the narrowest AWA, the crew should move aft, raising the bow and lowering the stern. The net effect is more stability and less chance of the rudder ventilating.

Sail Cloth Area Size
Reacher .85oz.Poly 120 m^2
Runner .6 oz. Poly or 165 m^2


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The AP Runner is designed to the class maximum. The luff flies straight and vertical which makes adjusting the luff curl easy. As the wind builds, pay attention to sail control and keeping the boat sailing on its feet. To maintain optimum trim, ease the tack line a few feet to allow the luff to fly upward and forward. In moderate to heavy air, the decision on whether to hoist the reacher or the runner can be determined by the sea state, number of crew and their collective experience.


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Keep a running chatter going between the helm and trimmer to select the best AWA for pressure and speed. The sheet and tiller adjustments should be automatic and 90% of the concentration between helm and trim should focus on the "speed groove" which keeps the pressure in the sail while maintaining optimum speed without increasing heel angle. The sheet grinder is an integral part of "the speed groove". A good exchange might sound like this: Trimmer: "Speed is down 2/10ths, lets head up 3 deg. - be ready for a couple feet of trim....Here it comes". Grinder: Starts trimming gently and ends gently to avoid disturbing the sail. As the wind builds, the verbal exchange gets louder, and the grinding must start earlier and more aggressively to keep the boat sailing fast, in the groove.


  • The more times you gybe in every windspeed possible, the faster your gybes will be. Your crew will gain confidence, especially in tight situations when a gybe can make the difference in mark rounding position. The helmsman will be able to sail offwind more aggressively knowing that the crew work is perfect.
  • Hoist the sail to the max, presenting the largest amount of sail area to mother nature*.
  • Initiate a gybe only when the sail is flying at its best.
  • Learn to tail the new sheet so fast the winch starts to smoke!
  • Ease off the tack line as conditions permit. The luff tension will help control the angle of attack on the forward 1/4 of the asymmetric.
  • Install telltales 2’ back from the luff at 3 locations up the luff. This will sharpen up your shape analysis.
  • Sail with minimum heel to allow as much of the sail as possible to rotate to weather.
  • "Keep the heat on the boiler". Use the sheet as an indicator of how low you can sail for the optimum VMG. If the sheet starts to droop, head up a few degrees until it is just pressurized. Watch the speed build and the AWA move forward. To maintain "heat", simply bear away until the speed begins to trend down, then head up a degree to keep it at full speed.



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