Miracle Tuning Guide by Sailboats Speedsails
Guides and Blogs
The aim of this tuning guide is to help you get the most out of your Miracle. 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 (L) controls the sideways pressure on the mast. Spreader deflection (D) controls the pre-bend. Both are measured from the mast.
| Setting (Alderbarren mast) | Measurement |
|---|---|
| Spreader Length (L) | 350mm |
| Spreader Deflection (D) | 140mm |
Rig Tension
Tension is measured on the shrouds; measure at the same height every time (eye level). Increasing the rig tension reduces jib luff sag and straightens the entry to the jib.
| Conditions | Rig Tension |
|---|---|
| Up to force 3 | ~180lbs |
| Force 3 and above | 240–280lbs |
Mast Position and Rake
The measurement between the aft transom and aft of mast foot should be 2580mm. Mast rake is measured from the top of the mast to the top of the transom; hoist the jib with 180lbs and cleat the main halyard in the normal position.
| Measurement | Value |
|---|---|
| Mast foot position (aft transom to aft of mast foot) | 2580mm |
| Mast rake range | 5791mm – 5842mm |
Jib Fairleads
The jib fairleads should be situated as far inboard as possible. They should be positioned so that when the jib is pulled tight the continuation of the jib sheet from the fairlead should meet a point 1170mm up from the base of the luff wire.
Kicking Strap
This is the most critical control when racing. In very light winds just have the slack taken out of the kicker when sailing upwind. 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 to de-power the mainsail in very windy conditions. Remember to release it when going downwind.
Outhaul
| Point of Sail / Conditions | Outhaul Setting |
|---|---|
| Upwind (all conditions) | Tight to the black band |
| Upwind – choppy (10–12 knots) | Eased up to 25mm |
| Reaches | Eased 35–50mm |
| Close spinnaker reach | Left on tight |
| Planning 2-sail reach | Eased 60mm |
| Run | Eased 10–15mm 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. If the wind drops and the spinnaker struggles to fly, dropping the pole a few inches can help it to set.
