GP14 Tuning Guide by Sailboats Speedsails

The aim of this tuning guide is to help you get the most out of your GP14. Although the following measurements should enable you to set your boat up close to its ideal settings, it is worth bearing in mind that it is only a guide and minor alterations may be required for different boats and helmsmen.

Spreader Settings

Spreader length controls the sideways pressure on the mast and is measured from the side wall of the mast to the shroud (A). Spreader deflection controls the pre-bend in the mast and is measured by putting a straight edge from shroud to shroud and then measuring from this edge to the nearest point on the luff groove (B).

Setting	Fat Top Mast	Slim Top Mast
Spreader Length (L)	360mm	380mm
Spreader Deflection (D)	155mm	150mm

Mast Step Position

The position to step the mast is obtained by measuring the distance (in a straight line) from the back of the transom to the furthest aft bolt in the mast step. This should be 2845mm in Mark 2 GP14s. In the Mark 1 boats, the mast should be stepped as far back as possible in the mast step. Hold the mast about ⅓ to ½ out of the gate and attach the shrouds. With the genoa up at 400lbs of rig tension there should be almost no gap between the halyard and the mast (i.e. straight mast). Pre-bend with the mast seated should be about ¾ inch.

Rig Tension

Conditions	Rig Tension
Drifter (under ~5 knots)	300lbs
Below 10 knots	350lbs
General sailing	400lbs
Very breezy (above 20 knots)	~440lbs (use caution on older boats)

Mast Rake

Mast rake is measured from the top of the mast to the top of the transom. It will vary between boats but should be in the range 21' 9" – 21' 11" (we sail with a rake of 21' 9½"). To do this, hoist the jib with 400lbs tension and measure 18' to the top of the black band at the gooseneck. Cleat the main halyard in this position and then measure the distance to the top of the transom.

Genoa

To ensure there is as small a gap as possible between the bottom of the deck and the Genoa, the tack of the Genoa should be as low as possible i.e. connected directly to the bow plate fitting. If the rig tension, mast rake and pre-bend are all set correctly the clew of the Genoa will be approximately 3 inches from the fairlead.

Genoa Fairleads

These should be set so that if you follow the angle of the genoa sheet through the clew, it almost bisects the angle formed by the clew and foot but sheets slightly more down the leech.

Conditions	Fairlead Setting
Crew to leeward (very light)	Eased up to 2 inches — crew eases in ½ inch increments as they move inboard
Crew in the middle	Approximately 1 inch eased from bar tight
Normal (crew sitting out)	Bar tight
Above 15 knots	Move back one hole — opens upper leech of jib
Above 20 knots	Move back two holes

Mainsail

The mainsail should only ever be hoisted to the bottom of the black band. In light winds the main should be lowered slightly so that it is approximately ½ inch below the black band.

Kicking Strap

This is the most critical control when racing. In very light winds just have the slack taken out of the kicker. As the wind starts to increase, aim to have the top leech telltale on the main flying approximately 80% of the time. Downwind this telltale should be flying continuously. Above 15 knots the kicking strap becomes a power control — if underpowered let some off, if overpowered pull more on.

Cunningham

The cunningham should only be used in a GP14 in 15 knots and above. In these conditions some cunningham may be used to remove excessive creases in the main luff. Do not remove the creases completely and do not use the cunningham when sailing downwind.

Outhaul

Point of Sail / Conditions	Outhaul Setting
Upwind (all conditions)	Tight to the black band
Upwind – choppy (10–12 knots)	Eased up to 1" to power up the mainsail
Reaches	Eased 1½ – 2"
Planning 2-sail reach	Eased 2½"
Close spinnaker reach	Left on tight
Run	Eased ½" only

Spinnaker

A stopper knot should be put into the spinnaker halyard so that when fully hoisted, the head of the spinnaker is about 3 inches from the mast. 90% of the time the spinnaker pole should be set so that both the tack and clew are level. If it starts to curl near the top then the pole is too high and vice versa. The fairleads should be at the widest point in the boat.