Honda CRF125F [2015 - 2021]: A Legacy of Approachable Off-Road Fun

Introduction

The Honda CRF125F represents one of the most accessible gateways into off-road motorcycling. Designed as a confidence-building machine for beginners and younger riders, this air-cooled workhorse has cemented its reputation as a forgiving, low-maintenance trail companion. From 2015 to 2021, Honda refined the formula with subtle tweaks, including the introduction of fuel injection in later models and the popular Big Wheel variant. After spending a day wrestling it through rocky trails and open fire roads, it’s clear why this bike remains a staple in garages and riding schools worldwide.

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Design & Ergonomics

Honda’s CRF lineage is instantly recognizable in the 125F’s aggressive styling, complete with red plastics, a minimalist headlight shroud (on Big Wheel models), and a no-nonsense steel diamond frame. The standard model’s 735mm (28.9-inch) seat height feels approachable for riders as short as 150cm (4’11”), while the Big Wheel’s 785mm (30.9-inch) perch caters to taller teens or adults dipping their toes into trail riding.

Standing over the bike, the narrow midsection allows easy ground reach, and the 88kg (194 lbs) curb weight – lighter than most full-size mountain bikes – inspires confidence when paddling through tricky sections. Controls are deliberately basic: a cable-operated clutch with a featherlight pull, a thumb-operated kill switch, and a digital CDI ignition system that’s virtually bulletproof.

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Engine & Performance

At the heart of the CRF125F lies a 124.9cc single-cylinder four-stroke engine, producing a modest 9 PS (6.6 kW) at 7,500 RPM and 10.2 Nm (7.5 lb-ft) of torque. While these numbers won’t set any speed records, the power delivery is where this mill shines.

Carbureted vs. Fuel-Injected Models
- 2015-2019: A 20mm piston-valve carburetor provides crisp throttle response, though it demands occasional jetting adjustments for altitude changes.
- 2020-2021: Honda introduced fuel injection with a 22mm throttle body, eliminating cold-start headaches and improving fuel efficiency to 40-45 km/L (94-106 mpg).

The 4-speed transmission (5-speed on select Big Wheel editions) features a forgiving clutch engagement zone, making it nearly impossible to stall. First gear crawls at walking pace over roots and rocks, while fourth gear tops out around 80 km/h (50 mph) – enough to feel thrilling for new riders but not intimidating.

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Suspension & Handling

Honda prioritized durability over adjustability here:
- Front: A 31mm telescopic fork with 132-150mm (5.2-5.9 inches) of travel absorbs small bumps competently but can feel overwhelmed at higher speeds.
- Rear: The Pro-Link single-shock setup offers 140-168mm (5.5-6.6 inches) of travel, depending on the year and model. Preload adjustment is absent, so heavier riders (>68kg / 150 lbs) might bottom out on hard landings.

Where the CRF125F truly excels is low-speed maneuverability. The short 1219-1255mm (48-49.4-inch) wheelbase and 25.3-27.3° rake angle let it pivot through tight singletrack like a mountain bike. The IRC tires – 70/100-17 front and 90/100-14 rear on standard models – provide predictable slide control on loose terrain.

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Braking System

Braking duties are handled by a 220mm hydraulic front disc (surprisingly potent for a bike this light) and a rear drum brake. Lever feel is wooden compared to premium dirt bikes, but the system’s simplicity aligns with the CRF’s ethos: fewer parts to break, cheaper to maintain.

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Competition

The CRF125F’s closest rivals include:

1. Yamaha TT-R125LE

• Pros: Adjustable suspension, slightly more power (11.4 PS).
• Cons: Heavier (94kg / 207 lbs), carburetor-only until discontinuation.

2. Kawasaki KLX140

• Pros: Larger 144cc engine, UNI-Trak rear suspension.
• Cons: Taller seat height (787mm / 31 inches), higher maintenance costs.

3. Suzuki DR-Z125

• Pros: Legendary durability, electric start option.
• Cons: Antiquated design, discontinued after 2018.

Verdict: The Honda strikes the best balance between accessibility and modern features, especially post-2020 with fuel injection. It’s the only bike in its class offering a Big Wheel variant straight from the factory.

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Maintenance

The CRF125F is a mechanic’s dream – or more accurately, a mechanic’s rarely-visited side project. Key considerations:

1. Oil Changes

• Frequency: Every 20 hours of runtime or 6 months.
• Oil Type: 1L of SAE 10W-30 (API SG or higher).
• Pro Tip: Install a reusable magnetic oil filter plug (available here) to catch metal shavings during break-in.

2. Valve Adjustments

• Specs: Intake 0.08-0.12mm (0.003-0.005"), Exhaust 0.13-0.17mm (0.005-0.007").
• Tool Recommendation: Use a .005" feeler gauge for exhaust valves to stay within tolerance.

3. Chain Care

• Sprocket Combo: 13T front / 49T rear.
• Upgrade Path: Swap to a DID 428MXU3 chain for longer lifespan in muddy conditions.

4. Carburetor Tuning (Pre-2020 Models)

• Pilot Jet: #35 (stock) works up to 1,500m (4,921 ft). For higher elevations, switch to a #30.

5. Winterization

• Fuel Stabilizer: Mandatory for ethanol-blended gas.
• Battery: Disconnect and store with a trickle charger.

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Conclusion

The Honda CRF125F isn’t about pushing limits – it’s about expanding them. Whether you’re a parent coaching a child through their first berms or an adult rediscovering the joy of dirt biking, this machine removes complexity from the equation. Its longevity in Honda’s lineup is no accident; it’s a masterclass in designing a motorcycle that prioritizes rider growth over raw specs.

For owners looking to personalize their CRF, MOTOPARTS.store offers everything from grippier footpegs to heavy-duty skid plates. Because while the bike thrives in stock form, a few strategic upgrades can transform it from a learner into a lifelong trail partner.

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Specifications sheet

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