What Is the Weight of a 25hp Yamaha 2-Stroke Outboard?

If you're searching for the weight of a 25hp Yamaha 2-stroke outboard motor, the answer depends on the model year, shaft length, and starting mechanism—but most units weigh between 137 to 158 lbs (62 to 72 kg). The lighter models, like the F25 with a 15-inch short shaft and manual start, tip the scales at just 137 lbs (62.1 kg), making it one of the lightest 25-horsepower outboards ever built¹. This guide breaks down exact weights by configuration, explains why weight matters for small boats, compares 2-stroke vs. 4-stroke performance, and helps you choose the right setup based on portability, boat size, and usage scenario.

Why Outboard Motor Weight Matters

⚙️ The weight of an outboard motor directly affects your boat’s balance, fuel efficiency, top speed, and ease of transport. For lightweight vessels—like jon boats, skiffs, dinghies, or inflatable pontoons—every pound counts. A heavy engine can cause stern squat, reduce planing ability, and make trailering or lifting difficult without assistance.

✅ Lighter motors are easier to tilt, carry, and install—especially important if you frequently remove the engine for storage or use a cart. The Yamaha 25hp 2-stroke stands out because it delivers full 25 horsepower while remaining significantly lighter than most 4-stroke equivalents.

Exact Weight by Model and Configuration

The dry weight (without fuel or oil) of a 25hp Yamaha 2-stroke varies depending on three main factors: shaft length, starting method, and control type. Below is a breakdown of common configurations:

Model	Shaft Length	Start Type	Control	Weight (lbs)	Weight (kg)
F25MHS	15" (Short)	Manual	Tiller	137	62.1
F25LHS	20" (Long)	Manual	Tiller	143	64.9
F25MES	15" (Short)	Electric + Manual	Tiller	148	67.1
F25LES	20" (Long)	Electric + Manual	Tiller	154	69.9
F25MLTR	15" (Short)	Manual	Remote	152	68.9
F25LLTR	20" (Long)	Manual	Remote	158	71.7

📌 Note: These weights are for older 2-stroke models produced before 2018. Yamaha discontinued its 2-stroke line in favor of cleaner, more efficient 4-stroke engines. However, used units remain popular due to their power-to-weight ratio and simplicity.

Short Shaft vs. Long Shaft: How It Affects Weight and Use

📏 Shaft length determines how deep the propeller sits in the water and whether the engine fits your transom. Short shaft (15") models are designed for transoms 15–16 inches tall, while long shaft (20") versions suit transoms 20–21 inches high.

🔸 Short Shaft (15"): Weighs less, ideal for smaller boats under 14 feet. Offers better weight distribution on lightweight hulls.
🔸 Long Shaft (20"): Adds about 6–10 lbs depending on configuration. Necessary for deeper-V hulls or boats with higher transoms to prevent ventilation and cavitation.

❗ Installing a short shaft on a tall transom can lead to poor water pressure, overheating, and loss of thrust. Always match shaft length to your boat’s transom height.

Manual Start vs. Electric Start: Trade-offs in Weight and Convenience

⚡ Adding electric start increases weight due to the inclusion of a starter motor, solenoid, and heavier wiring harness. On average, electric-start models weigh 10–12 lbs more than their manual-only counterparts.

• Manual Start (Recoil Pull Cord): Lightest option. Requires physical effort but eliminates battery dependency. Ideal for backup motors or minimalist setups.
• Electric Start (Battery-Powered): More convenient, especially in cold weather. Requires a 12V battery and added maintenance. Best for frequent users or larger boats where the extra weight is negligible.

🔧 Some models offer dual start (manual + electric), giving flexibility without sacrificing reliability. These fall in the middle range of weight distribution.

Tiller vs. Remote Control: Impact on Portability and Handling

📍 Tiller-controlled motors have the steering handle and throttle integrated into the engine, reducing system complexity and overall weight. They’re simpler to install and operate, especially on small craft.

🌐 Remote control models route throttle and shift controls to a cockpit-mounted console. While offering better ergonomics on larger boats, they add weight from cables, brackets, and additional hardware.

✅ For maximum portability and minimal setup, tiller models are preferred. Their compact design makes them easy to detach and store.

How Yamaha 2-Stroke Compares to 4-Stroke 25hp Motors

🔄 In recent years, Yamaha has shifted focus to 4-stroke engines like the F25, which now holds the title of lightest 25hp 4-stroke at around 139 lbs. But despite advancements, many users still seek out the older 2-stroke versions for specific reasons.

Feature	Yamaha 25hp 2-Stroke	Yamaha F25 4-Stroke (Current)
Engine Cycle	2-Stroke	4-Stroke
Dry Weight (Short Shaft)	137–148 lbs	139 lbs
Fuel Efficiency	Moderate (higher consumption)	Better (up to 20% more efficient)
Emissions	Higher (pre-EPA Tier III)	Lower (meets modern standards)
Power Delivery	Peaky, high RPM power	Smoother, broader torque curve
Maintenance	Simpler (fewer moving parts)	More complex (valve adjustments, oil changes)
Lifespan (with care)	2,000–3,000 hours	3,000+ hours

✨ While the current 4-stroke F25 nearly matches the 2-stroke in weight, the older 2-stroke offers a raw, responsive feel favored by some anglers and skiff users. However, 4-strokes run quieter, smoother, and meet modern environmental regulations.

Used Market Trends: Availability and Pricing (2024)

🛒 Although Yamaha no longer produces new 25hp 2-stroke outboards, they remain widely available on the used market. Prices vary based on condition, age, and features:

• F25MHS (15", Manual Start): $1,600–$2,200
• F25LHS (20", Manual Start): $1,800–$2,400
• F25MES/F25LES (Electric Start): $2,000–$2,800
• Remote-Control Models: $2,200–$3,000+

🔍 When buying used, inspect for corrosion, exhaust passage blockages, water in fuel system, and propeller damage. Check compression test results if possible. Engines from 2005–2010 are common; those stored indoors or flushed regularly tend to last longer.

Common Misconceptions About 2-Stroke Outboards

❌ Misconception #1: All 2-strokes are heavy and outdated.
Reality: The Yamaha 25hp 2-stroke was engineered for lightness and remains among the lightest in its class—even compared to modern 4-strokes.

❌ Misconception #2: 2-strokes don’t last as long.
Reality: With proper maintenance (correct oil mix, regular flushing, winterization), a 2-stroke can exceed 2,500 operating hours.

❌ Misconception #3: They’re illegal everywhere.
Reality: While banned on some inland lakes due to emissions, 2-strokes are still legal for saltwater and offshore use in most U.S. states and many international regions.

Real-World Use Cases: Who Still Uses the 25hp Yamaha 2-Stroke?

👥 Despite being phased out, this motor remains popular in several niches:

• Microskiff Anglers: Need lightweight power for shallow-water fishing. Every pound saved improves draft and maneuverability.
• Backup Motors: Lightweight enough to carry as a spare on larger vessels.
• DIY Boat Builders: Favor the simple design and ease of integration.
• International Markets: Still used in regions where fuel cost and availability favor 2-stroke simplicity.

How to Verify Weight Before Buying

📋 If you’re purchasing online or from a private seller, don’t rely solely on listed specs. Here’s how to confirm actual weight:

1. Check the OEM Specification Sheet: Look up the exact model number (e.g., F25MES) on Yamaha’s global site or archived brochures.
2. Ask for Scale Verification: Request that the seller weigh the unit with all attached components (prop, clamp, etc.).
3. Account for Accessories: Add ~5–10 lbs for mounting brackets, fuel tanks (if included), and protective covers.
4. Verify Dry vs. Wet Weight: Dry weight excludes oil and fuel; wet weight includes full fluids. Most listings use dry weight.

Maintenance Tips to Preserve Performance and Longevity

🧼 Keeping a 25hp Yamaha 2-stroke running well requires consistent care:

• Use Premium 2-Stroke Oil: Mix at 50:1 ratio unless specified otherwise. Avoid automotive oils.
• Flush After Every Saltwater Use: Prevents corrosion in powerhead and exhaust passages.
• Inspect Spark Plugs Monthly: NGK B8ES or equivalent. Replace every 100 hours.
• Check Fuel Lines and Primer Bulb: Cracked lines cause air leaks and hard starts.
• Winterize Properly: Fogging oil in cylinders, stabilize fuel, store upright.

Environmental and Regulatory Considerations

🌍 Emissions standards have largely driven the phaseout of 2-stroke engines. The EPA’s Clean Air Act and CARB regulations classify pre-Tier III 2-strokes as high-emission devices.

📌 Some U.S. states (e.g., California, New York) restrict 2-stroke use on certain lakes and rivers. Always check local regulations before operation. However, coastal and offshore use is generally unrestricted.

Alternatives to Consider

🔄 If you can’t find a reliable used 25hp 2-stroke or face regulatory limits, consider these alternatives:

• Yamaha F25 4-Stroke: Nearly same weight, much cleaner, warranty support.
• Tohatsu 25hp 2-Stroke (N25D/NE25D): One of the last remaining new-production 2-strokes, weighs ~143 lbs (manual start).
• 20hp Class Motors: Lighter options (e.g., Yamaha F20 at 121 lbs) may suffice for smaller boats.

Frequently Asked Questions

❓ What is the lightest 25hp Yamaha 2-stroke?
✅ The F25MHS (15" short shaft, manual start, tiller) is the lightest at 137 lbs (62.1 kg).

❓ Can I still buy a new Yamaha 25hp 2-stroke?
✅ No. Yamaha discontinued production after 2017. All available units are used or NOS (new old stock).

❓ How fast will a 25hp Yamaha 2-stroke go on a 14-foot boat?
✅ Top speed ranges from 25–32 mph depending on load, hull design, and prop pitch (typically 9"–10.5").

❓ Is the 25hp Yamaha 2-stroke reliable?
✅ Yes, when maintained properly. Known for durability, especially in saltwater environments with regular flushing.

❓ Why was the 25hp Yamaha 2-stroke discontinued?
✅ Due to tightening emissions regulations. Yamaha transitioned to cleaner 4-stroke technology across its lineup.