Review of Bonin 34

The hull is made of fibreglass. Generally, a hull made of fibreglass requires only a minimum of maintenance during the sailing season.
The hull is a double hull which improves the indoor climate. Especially when the water is colder than the air in the cabin, then the double hull insulates against cold water and reduce the condense water in the cabin.

The boat is equipped with 7 berths.

The boat equipped with 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.

The Bonin 34 is equipped with a fin keel. A boat with a fin keel is more manoeuvrable but has less directional stability than a similar boat with a long keel.

The boat can only enter major marinas as the draft is about 1.80 - 1.90 meter (5.91 - 6.21 ft) dependent on the load. See immersion rate below.

What is Capsize Screening Formula (CSF)?

The capsize screening value for Bonin 34 is 2.20, indicating that this boat would not be accepted to participate in ocean races.

Bonin 34 holds one CE certification:

The boat is by European Union certified as Class B. OFFSHORE:

What is Theoretical Maximum Hull Speed?

The theoretical maximal speed of a displacement boat of this length is 7.4 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 Bonin 34 is about 226 kg/cm, alternatively 1269 lbs/inch.
Meaning: if you load 226 kg cargo on the boat then it will sink 1 cm. Alternatively, if you load 1269 lbs cargo on the boat it will sink 1 inch.

What is Motion Comfort Ratio (MCR)?

The Motion Comfort Ratio for Bonin 34 is 18.1.

Comparing this ratio with similar sailboats show that it is more comfortable than 15% of all similar sailboat designs. This is a comfort value significantly below average.

What is L/B (Length Beam Ratio)?

The l/b ratio for Bonin 34 is 2.77.

Compared with other similar sailboats it is more spacy than 85% of all other designs. It seems that the designer has chosen a significantly more spacy hull design.

What is Displacement Length Ratio?

The DL-ratio for Bonin 34 is 150 which categorizes this boat among 'ultra light racers'.

86% of all similar sailboat designs are categorized as heavier. A light displacement requires less sailarea and has higher accellerations.

What is SA/D (Sail Area Displacement ratio)?

The SA/D for Bonin 34 with ISO 8666 reference sail is 18.3, with a 135% genua the SA/D is 21.6.

The SA/D ratio indicates that it is faster than 73% of all similar sailboat designs in light wind.

When buying anti-fouling bottom paint, it's nice to know how much to buy. The surface of the wet bottom is about 40m² (430 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.

Dimensions of sail for masthead rig.

Are your sails worn out? You might find your next sail here: Sails for Sale

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 shown boat owner's changes, improvements, etc. Here you might find inspiration for your boat.

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

We are always looking for new photos. If you can contribute with photos for Bonin 34 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.

[Ref 1]: ISO 8666 Small craft — Principal data.
[Ref 3]: ISO 12215-5 Small craft — Hull construction and scantlings.