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Beneteau First 235
From BENETEAU SERVICE - Sept. 1990

The First 235 has shown herself to be a successful club racer, and we have received many phone calls from owners inquiring about how to squeeze that extra bit of speed out of their boat.

We have listed a few tips that we have found to help the performance.

MAST TUNING - Z190 7/8 Rig

1) Set the boat up at a dock.

2) Loosen all rigging and set boom on deck.

3) Lengthen forestay to achieve maximum rake. You can even lengthen it another one and one-half inches from maximum by way of a shackle or longer plate. You can disconnect baby stay during tuning.

4) Set up mast straight in boat (athwartships). To do this, use your main halyard and measure to each side of boat on toerails in area of chainplates. Preferably measure from the bow back to ensure identical position on each side.

5) Set up uppers so that they are extremely tight. By this, prebend should be forced into mast (approximately 4" looking up track). Lowers should be completely slack during this period of tuning.

6) Take up the slack in lowers but do not make them bar tight. Pull up on the backstay hard and see that lowers start taking up load and limits the forward bend of the mast.

7) Release backstay and then decide whether you want to keep babystay rigged. If you remember to keep prebend in mast at all times, the babystay can be omitted. However, remember that failing this you could loose you mast especially in heavy weather under spinnaker.

Why have we suggested this tuning?

In light airs, especially, we have found the boat lacks weather helm, and in the case of the fin keel, actually has slight lee helm. We have found owners to set the leech of the main too hard in order to create weather helm and this tends to stop the boat in her tracks.


The long spreaders on the First 235 make sheeting positions extremely critical as a light genoa with a normal leech shape gets hooked up on the uppers very easily. We believe that a hollowed leech helps sail shape substantially. We also do not recommend going for a genoa larger than 150%.

In stronger winds do not hesitate to move your genoa lead further aft and sheet the genoa tight, as well as, tighten halyard tension so that the foot does not have too much fullness.

This has two effects:
1) It opens the crucial slot and reduces the backwinding on the main.

2) Flattens the genoa and moves the draft forward allowing for better pointing ability.


This is extremely important especially on the wing keel version. In light airs keep the boat floating on her lines and do not drag the transom. Therefore, you will normally have the helmsman in the cockpit, one crew member in the companionway, and the 3rd member to leeward on the sidedecks.

As the wind increases, slowly move your weight to weather and aft. In strong winds, keep everyone well aft and hiking to windward. You have to keep the rudder working.


The backstay is extremely important and generally follow this:

Light airs = No backstay tension
Medium airs = Medium backstay tension
Heavy airs = Hard backstay tension

Remember that in most conditions you should release the backstay when you go off wind, except in strong wind so that bend is kept in the mast. It is a good idea to mark your backstay so that you can revert back to similar settings easily.

The reasons for altering backstay tension has the following effects:

1) Light air: no backstay tension gives you fuller, more powerful sails.
2) Heavy air: Hard backstay tension tightens your forestay and moves the draft forward on the genoa. The mainsail is flattened out by the mast bending and opens the leech allowing the wind to spill out of the main easily.


Finally, and most importantly, if you want to race, strip your boat of all excess gear. Weight is extremely critical. However, it is up to you how serious you want to become. Keep the fun in it, but let's face it, the further up the results sheet you go, the more fun it is!

Try these suggestions. We're sure you will like the results.

Best of luck!




Z Spars in US

Click below to see
US Spars Z190|Z160 Info

See the US Spars Z190 & Z160 Info/Order page

US Spars Z190/Z160 Info Page


(aft-swept spreaders, backstay, no running backstays.)

1. Fore and Aft Tune

1.1 Mast Rake

  • Mast rake is determined by forestay length. Rake affects helm balance - raking the mast increases weather helm.

  • As a starting point, use the designed rake on the sailplan (ask the boat designer, not the mastmaker). If no information is available, start at 1:30. (eg 33 cm rake on a 10m mast). To measure rake, tension the backstay approximately 60%, then check rake with a weight attached to the main halyard. (Boat must be floating level when you do this!). Adjust forestay as necessary to obtain the desired angle.

1.2 Mast Bend

  • Check that the mast is upright athwartships in the boat. Use the main halyard to measure from the masthead to the chainplate each side. Adjust upper (cap) shrouds to get identical readings each side (but use minimal tension in the shrouds).

  • A certain amount of pre-set mast bend is desirable, to stabilise the middle part of the mast and thus minimise rig pump in a seaway.

  • Ensure the lower shrouds are slack. Induce the required amount of pre-bend in the mast by tensioning the backstay. (Make a note of the amount of pre-bend by using the main halyard tensioned down to the foot of the mast, and measuring the amount of bend at the spreaders). Tension the cap shrouds equally, a few turns at a time, until the fore and aft bend starts to increase. Check that the mast is still straight athwartships.

  • Now tighten the lowers in the same manner as the caps, until the fore and aft bend starts to decrease. At this stage the caps should be tighter than the lowers.

  • Release the tension in the backstay, check that you are happy with fore and aft and sideways deflections.

  • (Once the rig is set up as described here, tensioning the backstay whilst sailing will affect the curve in the upper part of the mast only, as the area around the spreaders is fixed by the opposing forces of the shrouds).

2. Transverse Tune

  • Go sailing! Set full sail to windward in smooth water in enough wind to induce 10-15 degrees heel when sailing to windward.

  • Tension the backstay just sufficiently to straighten the forestay.

  • If the leeward shrouds are slack, tighten them, but NO MORE THAN TWO TURNS AT A TIME. Go on the opposite tack and do likewise, then tack again and check if the lee shrouds are still slack. If so, repeat the operation. DO NOT OVERTIGHTEN the lee shrouds, as you may bend the boat or break the mast when you tack!

  • Back at the dock, check that the mast is still straight athwartships.

Z Spars UK provide the above for guidance only and on the understanding that it is the owner's responsiblity to set up his rig in a secure and seamanlike fashion.

©2003 kh -