Aft Cabin Karate Mk I Information, Review, Specs

Sailing Performance & Handling

Under sail, the Karate Mk I is a quintessential masthead sloop of its era. With a displacement that leans toward the heavier side of the spectrum—often cited around 4,500 to 5,000 kg—the boat exhibits a high degree of inertia and "seakindliness." This weight, combined with a ballast ratio that favors stability, ensures that the vessel remains remarkably composed in a chop. Editorial reviews from the era, such as those found in Bateaux.com, highlight its ability to maintain momentum through waves where lighter contemporary designs might stall.

The tracking is generally excellent due to the keel configuration, though the trade-off is a wider turning circle and some resistance to maneuvering in tight marina slips under power. While it is not a "light-air flyer," once the breeze hits 12–15 knots, the Karate Mk I finds its groove. The steering is often described by owners as heavy but communicative, providing a sense of security during offshore passages. Because the cockpit is positioned relatively high and forward to accommodate the aft cabin, the helmsman enjoys excellent visibility, though the ride can be slightly wetter in heavy headseas compared to the Karate Sport variant, which features a more traditional aft-cockpit arrangement.

Interior Comfort & Variations

The interior of the Karate Mk I Aft Cabin is defined by its unconventional layout. The primary living area includes a galley, a navigation station, and a U-shaped dinette that can often be converted into additional berths. The "Aft Cabin" designation refers to a dedicated sleeping space located behind the cockpit. On many Mk I models, this cabin is accessed via a separate companionway in the cockpit, effectively creating a private "guest suite" or a secluded owner’s retreat. This separation was a bold design choice that maximized the 3.25-meter beam, as noted in the technical archives of Voiles et Voiliers.

In contrast, the sibling model—the Karate Sport—utilizes the same hull but replaces the aft cabin with a larger, deeper cockpit and a more conventional interior flow. The Mk II variant, which followed in the late 1970s, refined the deck mold and updated the interior joinery. Inside the Mk I, one finds the heavy use of dark woods and laminates typical of the 1970s French "marine style," providing a warm, if somewhat enclosed, atmosphere. Headroom is generous in the main saloon, often exceeding 1.85 meters, making it a viable long-term cruiser for taller sailors.

Popular Mentions & Media

The Karate series holds a place of honor in French sailing culture, often appearing in regional literature as the "indestructible cruiser." It is frequently discussed in French maritime circles as a primary rival to the early Dufour and Jeanneau models of the same length. Its cultural footprint is most visible within the "Club des Amis Propriétaires de Karaté," an enduring owner association that maintains technical archives and organizes rallies along the French Atlantic coast. While it hasn't achieved the global cinematic fame of some bluewater brands, it remains a "cult classic" among European sailors who value the ruggedness of the CNSO "martial arts" lineage.

Known Issues & Buyer’s Checklist

Prospective buyers of a Karate Mk I should approach the vessel with an eye toward its half-century-old construction. While the hulls are notoriously overbuilt, specific areas require scrutiny:

• Osmotic Blistering: Like many early fiberglass boats from the 1970s, the Karate is prone to osmosis. A haul-out inspection is mandatory to check for hull moisture levels.
• Deck Delamination: The deck is a sandwich construction; soft spots around the chainplates or the mast step often indicate water ingress into the core material, requiring significant labor to repair.
• Engine Obsolescence: Many units were originally fitted with Perkins 4.108 or older Volvo Penta engines. Check for service records or evidence of a modern repower, as parts for original 1970s blocks are becoming increasingly scarce.
• Aft Cabin Seals: Because the aft cabin often has its own companionway hatch, the seals and drains around this entry point are common failure points, leading to dampness in the rear berths.
• Rudder Play: The rudder bearings on CNSO boats are known to wear, leading to vibration or "clunking" at the helm.

Community & Resources

The primary hub for technical knowledge is the Club des Amis Propriétaires de Karaté. This association provides a repository for original CNSO blueprints, rigging diagrams, and refurbishment advice specific to the Bigoin designs. For English-speaking owners, broader European cruising forums often host dedicated threads regarding the Karate’s seaworthiness for Atlantic crossings.

The Verdict

The CNSO Karate Mk I Aft Cabin is a rugged, character-filled cruiser that offers a unique layout for its size. It is an ideal choice for a buyer who prioritizes structural integrity and privacy over modern speed.

Pros:

• Extremely robust hull construction capable of serious offshore work.
• Unique aft cabin layout provides excellent privacy for a 33-foot vessel.
• Predictable, stable handling in heavy weather.
• Active owner community in Europe.

Cons:

• Heavy displacement results in sluggish performance in light winds.
• The separate aft cabin access can be inconvenient in rainy weather.
• Aged electrical and plumbing systems usually require a full refit.
• Difficult to maneuver in reverse due to the long fin keel and prop walk.