TM MX EN 144 [2008-2011]: An Italian Precision Tool for Dirt Dominance

Introduction

The TM MX EN 144 represents a fascinating chapter in off-road motorcycling history. Produced by Italy’s boutique manufacturer TM Racing between 2008 and 2011, this two-stroke machine was never meant for the masses. Instead, it catered to riders who valued hand-built quality, razor-sharp performance, and the unapologetic character of a race-ready two-stroke engine. Available in MX (motocross) and EN (enduro) variants, this generation balanced old-school two-stroke aggression with modern chassis geometry and suspension components. Let’s dissect why this Italian stallion remains a cult favorite among hardcore off-road enthusiasts.

Engine and Performance

The Heart of a Racehorse

At its core beats a 143.4 cc (8.75 cubic inches) liquid-cooled two-stroke engine. The 56 x 58.2 mm (2.2 x 2.3-inch) bore and stroke ratio leans toward high-revving power delivery, typical of small-displacement two-strokes designed for explosive acceleration.

The MX 144 variant features a 5-speed gearbox optimized for motocross track rhythms, while the EN 144 enduro model gets a wider-ratio 6-speed transmission to handle technical trails and hill climbs. Both use a Keihin PWK 38 carburetor—a proven choice for precise fuel metering—though jetting requires careful tuning depending on altitude and temperature.

What sets this engine apart is its 17.2:1 compression ratio (MX) and Kokusan CDI ignition with selectable maps (from 2010 onward). Flick the handlebar switch, and you alternate between a linear "traction" mode for slippery conditions and an aggressive "race" mode that unleashes a violent mid-to-top-end hit.

Riding Impressions:
- Low-end grunt: Surprisingly tractable for a 144cc engine, allowing clutch-modulated power in tight corners.
- Mid-range punch: The V-Force reed valve sharpens throttle response, making the bike leap forward when the pipe “comes on.”
- Top-end scream: Hold the throttle wide, and the engine revs freely to 11,500 RPM, though power signs off abruptly compared to modern fuel-injected rivals.

The hydraulic clutch (Nissin/Brembo components) offers buttery engagement, crucial for managing the two-stroke’s light-switch power delivery during starts or technical sections.

Chassis and Handling

Precision Meets Italian Flair

TM’s perimetral aluminum frame is a work of art. Weighing just 9.3 kg (20.5 lbs), it’s stiffer than steel alternatives, translating to razor-sharp cornering. The MX model uses 21”/19” wheels with Dunlop Geomax MX52-style tires (90/90-21 front, 100/90-19 rear), while the EN 144 swaps to a fatter 120/90-18 rear tire for enduro versatility.

Suspension Setup:
- Front: 50mm Marzocchi USD forks (MX) or adjustable Marzocchi USD units (EN). Optional Öhlins 48mm forks add plushness for pro-level riders.
- Rear: Sachs Boge shock (Öhlins optional) with high/low-speed compression damping.

On the Track/Trail:
The MX 144 feels like a scalpel on a motocross track. The chassis carves ruts with telepathic feedback, while the suspension handles big jumps (up to 15 meters/50 feet) without bottoming harshly. The EN 144’s longer suspension travel (310mm vs 300mm rear) soaks up rocky trails, though the stiff frame can feel unforgiving on square-edge hits at low speed.

Braking: Nissin master cylinders paired with Brembo calipers deliver strong stopping power. The 245mm (9.6”) discs bite harder than Japanese counterparts—a blessing for experts but potentially overwhelming for beginners.

Competition

How the TM Stacks Up Against Rivals

1. KTM 150 SX (2009-2011):
- Lighter feel (98 kg vs TM’s 102 kg wet)
- Wider dealer network
- TM counters with superior suspension components (stock vs stock) and hand-built exclusivity

2. Husqvarna WR 150:
- Softer power delivery suited to enduro
- TM’s MX 144 dominates in peak horsepower (43 HP vs 39 HP)
- Husky’s plastics and ergonomics feel more modern

3. GasGas MC 125:
- Lacks the TM’s mid-range punch
- Cheaper maintenance costs
- TM’s aluminum frame offers better feedback

Verdict: The TM doesn’t just compete—it humiliates rivals in build quality and race-ready specs. However, parts availability and resale value lag behind Austrian brands. This is a bike for riders who prioritize performance over practicality.

Maintenance

Keeping the Italian Fire Alive

1. Engine Care:
- Piston replacements: Every 30-40 hours for aggressive riders. Use Vertex or ProX kits (available at MOTOPARTS.store).
- Crank rebuilds: Inspect every 100 hours. Watch for main bearing play.
- Carb tuning: The Keihin PWK 38 thrives with JD Jet Kits (we stock these!) to handle altitude changes.

2. Suspension Servicing:
- Change fork oil every 50 hours. Use Motorex 5W for Marzocchi forks.
- Sachs shock rebuilds: Replace seals annually if ridden weekly.

3. Brake Upgrades:
- Swap to Galfer wave rotors for better mud clearance.
- MOTOPARTS.store recommends TRW sintered pads for aggressive bite.

4. Critical Spares to Keep:
- Reed valve petals (V-Force 3 replacement cages available)
- Clutch plates (Brembo OEM kits in stock)
- Air filters (Twin Air prefits with our custom TM Racing logo)

Pro Tip: The 3.5% oil mixture (1:28.5 ratio) works best with Motul 710 two-stroke oil. Avoid cheaper oils to prevent powervalve gumming.

Conclusion

The TM MX EN 144 generation isn’t a motorcycle—it’s a statement. From its hand-welded frame to the race-spec suspension, every detail screams "no compromises." While newer bikes offer easier maintenance and tamer powerbands, few can match the TM’s raw connection between rider and terrain. It’s the perfect project bike for experts wanting to personalize their weapon or collectors seeking a rare gem.

At MOTOPARTS.store, we’re ready to support your TM Racing journey with OEM and upgraded components. Whether you need a fresh set of Metzeler tires for enduro duty or an FMF exhaust to unleash hidden horsepower, our catalog has you covered. Ride hard, wrench smart, and let the Italian stallion roar.

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Specifications sheet

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