TWMX First Impression: 2005 Honda CR125R

¿They still make a CR125R?¿ As funny as they are, those were the first words out of Grant Young, as he watched his son¿and TWMX test rider¿Michael Young, pound out lap after lap aboard our new test bike at Racetown 395 yesterday. In a day and age that is dominated by 250cc four-strokes, two-stroke 125s are becoming a more and more rare sight to see at racetracks, even at the local level. That, plus the fact that the Honda CR125R is the last ¿05 tiddler to hit dealership floors, and it¿s easy to see why Michael¿s dad blurted those words out right in front of some of the Honda brass on hand for the intro.

As funny as that sounds, and as rare as 125s are becoming at the racetrack, however, the fact remains that next to Yamaha, Honda owns the biggest share of 125cc bike sales in the United States. Furthermore, there are thousands and thousands of riders out there who don¿t necessarily take their bikes to the track. Throw in the die-hard two-stroke fanatics who don¿t want to make the valve-and-cam conversion, plus the smaller riders making the transition from a mini bike, and it¿s easy to see why there is still plenty of demand for a 125cc two-stroke.

For 2005, Honda focused on coaxing more power out of the CR125R motor, which has been less than impressive for as long as its been wrapped inside an aluminum chassis. Plenty of motor changes were made to the new bike¿the most significant being a mechanical power valve instead of electronic¿and we were anxious to see if the best handling 125 now had the motor to match.

We¿ll cut to the chase, right from the get-go: the new CR125R motor is the best it¿s been in eight years! Believe it or not, this year¿s bike packs an impressive punch down low, with snappy throttle response and good torque. The mid-range pull is impressive as well, just like it has been for the past several years, but power falls off as the rpms begin to climb. In a nutshell: unlike previous 125cc Honda motors that were all mid-range, the 2005 powerplant now boasts some healthy power down low to go along with the middle rpm power, but it still falls flat up top. This isn¿t the best 125cc motor we¿ve tested in 2005, but at least it¿s now in the hunt.

Where the CR125R really shines, meanwhile, is in the suspension and handling department. As it always has, the CR125R is an incredible handling machine that inspires complete rider confidence. Light, nimble and extremely flickable, the CR125R does everything, and does it all well. Suspension action is very good, though heavier or faster riders may opt for stiffer springs.

Overall, the Honda CR125R remains an awesome handling machine , but this year boasts a much-improved motor to go along with the rest of the excellent package. Is it the best 125 for race applications? No; that would be the CRF250R. Compared against two-strokes only, however, the new CR125R is a viable option and a solid contender. Stay tuned for the TransWorld Motocross 125cc Shootout, which is just around the corner!

To see the new bike in action, click the video link under the first photo at the top of the article.

New for 2005

  • New crankcase intake tract and six-petal reed valve for more efficient air flow and improved drivability.
  • New thicker reed plates for better off-idle response.
  • Redesigned cylinder and cylinder head for improved power.
  • New crankshaft design for improved performance.
  • New piston features single keystone piston ring for improved sealing.
  • Revised coolant flow for improved engine cooling and increased engine performance.
  • Thicker radiator core (from 24mm to 28mm) improves cooling capacity to handle extra power.
  • New RC valve changed from electrical to governor actuation for better sealing and improved power characteristics.
  • New carb jetting specificationto match new engine characteristics.
  • New shift fork shaft, shift forks and shift drum for improved shifting performance.
  • ACG rotor weight increased to improve drivability.
  • New KYB fork features new fork damper that separates air and oil for reduced contamination and more consistent fork action.
  • New front axle placement for improved fork action and turning.
  • New swingarm features a dual-axis, double-taper design with a large cast aluminum cross member that is lighter weight and stronger.
  • New rear hub is stronger and lighter.
  • New Honda Racing-inspired graphics.

Engine/Drivetrain

  • Liquid-cooled two-stroke single-cylinder engine with 54mm x 54.5mm bore and stroke and 8.6:1 compression ratio.
  • Nikasil®-plated cylinder reduces friction and heat to improve overall performance.
  • Piston ring groove is anodized for added durability.
  • Air-intake boot is shaped for direct airflow and better low-speed engine performance.
  • Foam gasket between airbox and air boot for better sealing and airflow management.
  • 38mm Mikuni TMX carburetor with throttle position sensor (TPS).
  • Carbon fiber six-petal reed valve with sub reeds is designed for better top-end and low-end power.
  • Exhaust port is reshaped to improve top-end and over-rev power delivery.
  • RC-style exhaust valve features an NSR road racing-inspired rotary flap design with electronic control that provides a smooth power transition between low- and mid-range engine speeds. Redesigned exhaust valve flap features more overlap to minimize exhaust gas leakage between flap and cylinder.
  • Exhaust header is designed to improve low-end and over-rev power delivery. The expansion chamber design enhances the engine’s power output and delivery.
  • A four-pole ACG design produces a high-voltage spark throughout the rpm range with low magnetic drag, thus permitting a freer-revving engine.
  • A 16-bit processor in the ignition CPU produces immediate data calculation and extremely accurate ignition timing for the digital ignition.
  • Eight clutch plates provide significant surface area to handle the engine’s torque. Clutch springs provide a light feel at the lever.
  • Dual radiators permit forward engine placement and provide significant cooling capacity.
  • Steel water-pump gear and steel kickstarter-shaft collar enhance reliability.
  • Primary kickstarting system allows starting in any gear.

Chassis/Suspension

  • CR®125R’s third-generation twin-spar aluminum frame features taller swingarm pivot plates and thinner frame spars to create a narrower overall frame cross-section, and is also lighter than the second-generation frame.
  • Semi-double-cradle design features a single, large-diameter tapered downtube. Two rugged box-section rails attach to the base of the downtube and support the engine. A forged aluminum steering head provides a compact and extremely durable mount for the frame spars and engine downtube.
  • Front and rear wheels feature HRC® works-type lightweight aluminum spoke nipples.
  • Front wheel features large-diameter front axle and wide wheel-bearing span for additional rigidity.
  • Optional 20-inch front wheel improves cornering traction and rider comfort.
  • Rear axle diameter of 25mm and large-diameter bearings provide significant rigidity to withstand torturous track conditions.
  • Inverted Kayaba fork features a new twin-chamber design that separates air and oil for reduced contamination and more consistent fork action. Inner surface of fork’s outer tubes is honed to retain a thin coating of lubricating oil to reduce friction with fork bushings.
  • Pro-Link® single-shock rear suspension system features a fully adjustable Kayaba rear shock with 12.5 inches of travel, separate low-speed (18 positions) and high-speed (two turns) compression damping adjusters, and 30-position rebound damping. The adjusters are located together in a concentric fashion, with a screw inside a nut.
  • Compact twin-piston front brake caliper, anodized aluminum brake pistons and lightweight front brake disc reduce unsprung weight for improved turning and handling.
  • Lightweight HRC works-type rear brake system.
  • Large, 240mm front and rear brake rotors to provide optimum braking control.

Additional Features

  • Frame allows sidecovers to have larger air intake openings, with new inner ducts added to significantly increase airflow in low-rpm range.
  • Seat follows the shape of the fuel tank, providing a smooth transition to increase rider mobility and comfort.
  • “Non-slip” seat cover for increased rider control.
  • Wide, cleated stainless steel footpegs are improved for self-cleaning, corrosion resistance, provide excellent grip and fold for extra ground clearance.
  • Cleated rear brake pedal, shift lever and folding shift lever tip are made of lightweight aluminum.
  • Adjustable front brake lever for optimum control.
  • Quick-adjust clutch perch.
  • Aluminum Renthal 971 bend handlebar is rubber-mounted to reduce rider fatigue and improve comfort.
  • CR handlebar holders provide three different mounting positions: standard CR125R holder provides a 3mm rearward set and can be rotated 180 degrees to position handlebar 6mm forward. Optional holders (CR250R-type) provide neutral position to match rider preference.
  • Works-type handlebar grips add to rider comfort.
  • Front disc brake cover helps protect rotor and caliper from damage.
  • Removable rear subframe allows easy maintenance.
  • Dunlop D742 front and D756 rear tires for optimum traction and cornering.
  • Washable, two-stage foam air filter for optimal engine protection and easy maintenance.
  • Repackable silencer for maximum performance and minimal noise.
  • Stainless steel clutch cable for long life.

Specifications

Model: CR125R
Engine Type: 125cc liquid-cooled single-cylinder two-stroke with RC valve
Bore and Stroke: 54mm x 54.5mm
Compression Ratio: 8.6:1
Induction: Six-petal crankcase reed-valve
Carburetion: 38mm Mikuni TMX with throttle position sensor (TPS)
Ignition: Digital ignition with three-dimensional mapping and electronic advance
Transmission: Close-ratio five-speed
Final Drive: #520 chain; 13T/52T

Suspension     

Front: 46mm inverted Kayaba cartridge fork with 18-position rebound and 20-position compression damping adjustability; 12.0 inches travel
Rear: Pro-Link Kayaba single shock with spring preload, 30-position rebound damping adjustability, and compression damping adjustment separated into low-speed (18 positions) and high-speed (two turns); 12.5 inches travel

Brakes

Front: Single 240mm disc with twin-piston caliper
Rear: Single 240mm disc

Tires   

Front: 80/100-21
Rear: 100/90-19
Wheelbase: 57.48 inches
Rake (Caster Angle): 25.48°
Trail: 101.3mm (3.99 inches)
Seat Height: 37.3 inches
Ground Clearance: 13.7 inches
Dry Weight: 197.0 pounds
Fuel Capacity: 2.0 gallons
Color: Red

                                   

compression damping adjusters, and 30-position rebound damping. The adjusters are located together in a concentric fashion, with a screw inside a nut.

  • Compact twin-piston front brake caliper, anodized aluminum brake pistons and lightweight front brake disc reduce unsprung weight for improved turning and handling.
  • Lightweight HRC works-type rear brake system.
  • Large, 240mm front and rear brake rotors to provide optimum braking control.
  • Additional Features

    • Frame allows sidecovers to have larger air intake openings, with new inner ducts added to significantly increase airflow in low-rpm range.
    • Seat follows the shape of the fuel tank, providing a smooth transition to increase rider mobility and comfort.
    • “Non-slip” seat cover for increased rider control.
    • Wide, cleated stainless steel footpegs are improved for self-cleaning, corrosion resistance, provide excellent grip and fold for extra ground clearance.
    • Cleated rear brake pedal, shift lever and folding shift lever tip are made of lightweight aluminum.
    • Adjustable front brake lever for optimum control.
    • Quick-adjust clutch perch.
    • Aluminum Renthal 971 bend handlebar is rubber-mounted to reduce rider fatigue and improve comfort.
    • CR handlebar holders provide three different mounting positions: standard CR125R holder provides a 3mm rearward set and can be rotated 180 degrees to position handlebar 6mm forward. Optional holders (CR250R-type) provide neutral position to match rider preference.
    • Works-type handlebar grips add to rider comfort.
    • Front disc brake cover helps protect rotor and caliper from damage.
    • Removable rear subframe allows easy maintenance.
    • Dunlop D742 front and D756 rear tires for optimum traction and cornering.
    • Washable, two-stage foam air filter for optimal engine protection and easy maintenance.
    • Repackable silencer for maximum performance and minimal noise.
    • Stainless steel clutch cable for long life.

    Specifications

    Model: CR125R
    Engine Type: 125cc liquid-cooled single-cylinder two-stroke with RC valve
    Bore and Stroke: 54mm x 54.5mm
    Compression Ratio: 8.6:1
    Induction: Six-petal crankcase reed-valve
    Carburetion: 38mm Mikuni TMX with throttle position sensor (TPS)
    Ignition: Digital ignition with three-dimensional mapping and electronic advance
    Transmission: Close-ratio five-speed
    Final Drive: #520 chain; 13T/52T

    Suspension     

    Front: 46mm inverted Kayaba cartridge fork with 18-position rebound and 20-position compression damping adjustability; 12.0 inches travel
    Rear: Pro-Link Kayaba single shock with spring preload, 30-position rebound damping adjustability, and compression damping adjustment separated into low-speed (18 positions) and high-speed (two turns); 12.5 inches travel

    Brakes

    Front: Single 240mm disc with twin-piston caliper
    Rear: Single 240mm disc

    Tires   

    Front: 80/100-21
    Rear: 100/90-19
    Wheelbase: 57.48 inches
    Rake (Caster Angle): 25.48°
    Trail: 101.3mm (3.99 inches)
    Seat Height: 37.3 inches
    Ground Clearance: 13.7 inches
    Dry Weight: 197.0 pounds
    Fuel Capacity: 2.0 gallons
    Color: Red