RM 900 Sailboat Review, Specs, and Listings

Design Brief & Intent

The core mission of the RM 900 was to bridge the gap between high-performance offshore racing designs and practical, low-maintenance coastal cruising. During an era when mass-market builders were focusing on high-volume, deep-draft fiberglass monohulls, the RM 900 offered a radical alternative. Its hull was constructed using multi-chine marine plywood panels bonded and encapsulated in structural epoxy resin. This method yielded an incredibly stiff and lightweight structure with thermal and acoustic insulation far superior to single-skin GRP.

Inside, the boat was a complete departure from the dark, cavernous interiors of the late 1980s. The cabin featured a bright, uncluttered layout with a pearl-grey painted finish, direct access to the bare wooden hull, and excellent natural light provided by the forward-facing coachroof windows. The open-plan design and lack of a traditional closed-off forward bulkhead maximized the feeling of interior volume, though it offered less privacy than traditional layouts. To cater to experienced cruisers, the nav station and galley were prioritized with secure, sea-kindly positioning. The absence of inner liners meant that bilge access was absolute, a feature highly prized by blue-water cruisers who demanded the ability to quickly locate and repair any hull penetration.

Variations & Configurations

Throughout its production run, the RM 900 saw several key refinements and rigging configurations. Early hulls featured a transom that ended more abruptly, resulting in a hull length closer to nine meters. Later production models, starting around hull number forty-three, incorporated a factory-molded, integrated stern sugar scoop that extended the overall length to 9.32 meters, significantly improving boarding access and water-plane length.

The rig configurations were equally progressive. The standard arrangement was a fractional sloop with a Bergström-Ridder style spar. This setup featured highly swept-back spreaders and no permanent backstay, allowing for a large, full-roach mainsail with an aggressive leach profile. To control mast pump and forestay sag in heavy air, running backstays were utilized. A "Performance" or "Régate" tall-mast option was also made available, which was highly popular with training organizations like Les Glénans, as it offered exceptional light-air performance but demanded active reefing as the breeze built.

Structurally, the RM 900’s keel arrangement was unique. While most twin-keel designs suffer from localized stress and flexing on the hull bottom, Devriese solved this by laminating a massive, 960-kilogram cast-iron structural plate directly into the bilge. The two outer 170-kilogram cast-iron twin-keel fins were then bolted directly through the plywood hull into this heavy internal frame, distributing all grounding and righting loads across the entire structural grid of the boat. Another remarkable standard feature was the active water-ballast system: two lateral 200-liter freshwater tanks situated outboard of the companionway. Cruisers could open a manual gravity-drain valve to transfer 100 to 200 liters of water from the leeward tank to the windward tank during a long tack, effectively utilizing their drinking water supply to reduce heel and improve sailing trim.

Sailing Performance & Handling

Under sail, the RM 900 is a lively, responsive, and deceptively quick cruiser. Interpreting its design ratios reveals its physical character on the water. With a light-displacement-to-length ratio of 157.88, the boat sits firmly in the light-to-moderate displacement category, allowing it to easily transition from displacement speeds to planing downwind. Its sail-area-to-displacement ratio of 25.91 is exceptionally high for a cruiser, indicating an immensely powerful rig that excels in light airs but requires active, proactive reefing as the breeze builds.

The ballast-to-displacement ratio of 39.4 percent, combined with its wide 3.54-meter beam, provides high initial stability once the boat heels and digs its wide, hard chine into the water. However, its comfort ratio of 15.14 is low, reflecting its flat-bottomed, planing-oriented hull form. In a short, steep head sea, the RM 900 will ride actively and slam or tap violently if pressed too hard upwind. Conversely, once cracked off the wind to a reach or a run, the boat is in its element. Under an asymmetric spinnaker or gennaker, the wide stern and flat aft sections allow it to plane smoothly and maintain high average speeds with remarkable directional stability.

The handling at the helm is highly sensitive. Because the RM 900 uses a single, deep central rudder rather than twin rudders, the helmsman must be mindful of the boat’s heel angle. If the boat is allowed to heel excessively, the rudder can stall or ventilate as it lifts toward the aerated surface water. Keeping the boat relatively flat by utilizing the water ballasts and dropping a reef in the mainsail when the apparent wind exceeds fifteen knots ensures the single rudder retains absolute grip and authority.

Market Snapshot & Economics

Decades after its introduction, the RM 900 enjoys a passionate cult following, particularly in France, Brittany, and the UK. Because RM Yachts has built an elite reputation for high-performance, eco-friendly wooden-epoxy cruisers, the RM 900 acts as an affordable entry point into this prestigious brand. Consequently, well-maintained examples command a notable price premium on the secondary market compared to contemporary mass-production fiberglass cruisers of the same length.

However, prospective buyers must evaluate these boats with a distinct set of economic expectations. Unlike a fiberglass hull that can survive years of neglect with only cosmetic deterioration, an epoxy-plywood hull requires rigorous preventative maintenance. Buying a neglected RM 900 at a discount can quickly become a financial liability if there is extensive freshwater rot in the deck or cabin top. Conversely, a structurally sound hull that has been stored dry or kept under a high-quality protective cover represents exceptional value, offering ocean-going capability and structural longevity that rivals modern yachts costing many times more.

Known Issues & Triage

The primary vulnerability of any epoxy-plywood vessel is freshwater infiltration. While the outer hull is protected by layers of fiberglass and epoxy, the deck and coachroof joints are prone to wear.

Deck and Coachroof Paint Degradation: The polyurethane paint and epoxy barrier coats on the deck must be monitored constantly. UV exposure will eventually cause micro-cracking, particularly around high-stress areas like chainplates, stanchion bases, and the cabin window tracks. If water penetrates the epoxy barrier, it will saturate the underlying marine plywood. Triage requires sanding back the affected area, drying the timber completely, treating it with a penetrating epoxy sealer, and re-applying structural fiberglass tape or paint.
Window and Hatch Leaks: The large, signature plexiglass cabin windows on the RM 900 are held in place with structural adhesives and mechanical fasteners. Over time, flexing and thermal expansion can break the adhesive seal, allowing rainwater to seep behind the panels. Because there is no internal headliner, these leaks are immediately visible as dark stains on the interior plywood. The fix involves removing the windows, scraping away the old sealant, preparing the wood with an epoxy primer, and re-bedding the plexiglass with high-quality marine adhesive sealants.
Keel Joint and Internal Frame Corrosion: The heavy internal cast-iron structural plate and the external twin-keel joints must be inspected for signs of weeping or rust. If water penetrates the external keel-to-hull seam, galvanic action can occur between the cast-iron keels and the mounting fasteners. Refitting requires hauling the boat, removing the keel bolts, grinding away rust, re-sealing the joint with structural epoxy filler, and re-bedding the keels with a flexible polyurethane sealant.
Single Rudder Bearings: Due to the high loads placed on the single rudder when the boat is sailing downwind in a breeze, the rudder stock bearings and the skeg attachment point can develop play. Owners should inspect the rudder play annually and replace the nylon or bronze bushings if any movement is detected.

The Verdict

The RM 900 remains an outstanding choice for adventurous cruisers who value structural stiffness, thermal comfort, and the unique ability to dry out on any sandy beach. It is a true sailor's boat, requiring active management of its powerful rig and single rudder, but rewarding its crew with exhilarating off-wind performance and an incredibly dry, condensation-free interior. While it is not a low-maintenance plastic boat and demands an owner who is willing to monitor paint coatings and seals diligently, it stands as a testament to the brilliance of epoxy-plywood construction.