Review of Motiva 39

The deck is made of steel.

The boat is equipped with 4 cabins, 8 berths, a galley, 380.0 liter fresh water capacity and toilet facility.

Note: the boat has also been sold to be self-made/-interiored, which means that the quality of each boat may vary.

Rig of Motiva 39 anno 1975. Modified Kiel 1,85 And made for Explore Diving Diving Yacht Delfi. Total Modified for Offshore Used and wreck Diving

Motiva 39 has more than one rig.

One option is a ketch rig. A ketch rig is generally considered easier to handle, because the sails are smaller, and because it can sail on most points to the wind with one sail completely taken down for repair or while reefing. The sail configuration of a ketch allows for better comfort and stability when sailing downwind or on a broad reach.

Another option is a masthead rig. The advantage of a masthead rig is its simplicity and the fact that a given sail area - compared with a fractional rig - can be carried lower and thus with less heeling moment.

Full keel

The Motiva 39 is equipped with a long keel. A full keel provide a better directional stability than a similar boat with a fin keel; on the other hand, better directional stability means also that the boat is more difficult to handle in a harbour with less space.

The keel is made of lead. Compared with iron, lead has the advantage of being 44% heavier, which allows a smaller keel and hence less water resistance and higher speed.

The boat can enter most marinas as the draft is just about 1.50 - 1.60 meter (4.92 - 5.22 ft) dependent on the load. See immersion rate below.

The boat may be equipped with an inboard Ford engine at 90 hp (67 kW). The speed is 10.0 knots.

The transmission is a shaft drive. A shaft drive will in the long run require less maintenance than other types of drive e.g. a sail drive.

The fuel tank, which is made of steel, has a capacity of 800.0 liters (211 US gallons, 175 imperial gallons).

What is Capsize Screening Formula (CSF)?

The capsize screening value for Motiva 39 is 1.47, indicating that this boat could - if evaluated by this formula alone - be accepted to participate in ocean races.

What is Theoretical Maximum Hull Speed?

The theoretical maximal speed of a displacement boat of this length is 7.7 knots. The term "Theoretical Maximum Hull Speed" is widely used even though a boat can sail faster. The term shall be interpreted as above the theoretical speed a great additional power is necessary for a small gain in speed.

The immersion rate is defined as the weight required to sink the boat a certain level. The immersion rate for Motiva 39 is about 218 kg/cm, alternatively 1225 lbs/inch.
Meaning: if you load 218 kg cargo on the boat then it will sink 1 cm. Alternatively, if you load 1225 lbs cargo on the boat it will sink 1 inch.

What is Motion Comfort Ratio (MCR)?

The Motion Comfort Ratio for Motiva 39 is 45.7.

What is L/B (Length Beam Ratio)?

The l/b ratio for Motiva 39 is 3.68.

What is a Ballast Ratio?

The ballast ratio for Motiva 39 is 27%.

What is Displacement Length Ratio?

The DL-ratio for Motiva 39 is 302 which categorizes this boat among 'medium weight cruisers'.

When buying anti-fouling bottom paint, it's nice to know how much to buy. The surface of the wet bottom is about 36m² (387 ft²).
Based on this, your favourite maritime shop can tell you the quantity you need.

Note: If you use a paint roller you will need more paint than if you use a paintbrush.

If you need to renew parts of your running rig and is not quite sure of the dimensions, you may find the estimates computed below useful.

This section is reserved boat owner's modifications, improvements, etc. Here you might find (or contribute with) inspiration for your boat.

Do you have changes/improvements you would like to share? Upload a photo and describe what you have done.

We are always looking for new photos. If you can contribute with photos for Motiva 39 it would be a great help.

If you have any comments to the review, improvement suggestions, or the like, feel free to contact us. Criticism helps us to improve.