Honda TRX450R Specs and Review

Red 2014 Honda TRX450R ATV

A true embodiment of racing, the Honda TRX450R’s durable design and unparalleled power mill allowed it to stand atop numerous podiums the world over.

Many anticipated this Baja winner to sport sharper, more aggressive plastics and a fuel-injected motor down the road. But roll-cage-equipped machines soon took over the sport ATV scene. And it was not until the recent rise of two-strokes that off-roaders started to think back on this 450-class racer.

The Honda TRX450R (a.k.a. Honda SporTrax 450R) is a championship-winning quad released in the market from 2004 to 2014. Boasting a 449-cm3 2-stroke engine, 74-mph top speed, and race-inspired chassis, this 4×4 secured its place in history by winning four victories in the grueling Baja 1000.

Although highly-acclaimed on the race tracks, the Honda TRX 450R did not step into the ATV landscape with guns blazing. It was not until its penultimate year that the TRX450R ranked 2nd out of 30 sport ATVs and released its best, special-edition trims. Despite its late display of strength, the quad has long been regarded for its race-worthiness.

The Baja-Winning Honda

For the entirety of its production, the Honda TRX450R has been a tested-and-proven winner on motocross and off-road racing circuits. Refined, powerful, and agile, the 450-class machine offered excellent maneuverability on the tracks and even on dunes and trails.

From the get-go, the quad has been destined for a Baja-winning heritage – with a no-frills design meant for high-performance riding and the ability to get out of the pits fast.

Although rumored to take its power mill from the award-winning Honda CRF450R and CRF450X engines, the TRX450R initially upset several enthusiasts who thought the quad’s engine felt underpowered. Luckily, this did not deter most consumers from getting their hands on the trusty, capable machine.

A couple of years from its inception, Honda finally made developmental changes on the 4×4 (detailed in a later section of this article) that brought it closer to the Honda 450R.

Features

Unlike how present-day 4x4s are fashioned, the Honda TRX450R is not ideal for the beginner rider. Some of its features, such as the Unicam® valve train, Keihin FCR-type carburetor, championship-geared suspension system, and other components – along with its aggressive nature – best work in the capable hands of a more experienced operator.

It is but natural for this four-wheeler widely known as the off-roading pro’s weapon of choice. And true enough – the TRX450R became the first factory-sponsored quad piloted by Tim Farr to compete in the ATVA MX, TT Nationals in the Pro-Production class, and the 2003 Baja 1000 nationals.

Catch a glimpse of a Honda TRX450R turned John-Deere-themed desert assassin in this video by Dirt Wheels Magazine:

Honda TRX450R Specs (2004 Honda TRX 450R vs. 2009 Model)

Engine & Lubrication

Despite initial beliefs that the SporTrax 450R entirely came from the (Honda 450R) CRF450R dirt bike’s power mill, the only thing these two machines have in common is their displacement.

It was not until 2006 that Honda overhauled the TRX 450R to bring its mechanical components closer to its motorcycle variant. These led to an improvement in power output from 33 hp to 41 hp.

Of course, adjusting the 4×4 jetting beyond 1,500 meters (4,500 feet) is still necessary, as high-altitude riding results in a rich mixture that can adversely affect engine performance or power delivery, increase fuel consumption, or drivability problems.

2004 – 2005 Honda TRX450R Post-’05 TRX450R,
’07-’09 TRX450R-ER
Engine Type 4-Stroke SOHC
Cylinder Arrangement Single cylinder, transversely installed
Carburetion System 42-mm round-slide Keihin FCR Carburetor w/ TPS x 1 40-mm flat-slide Keihin FCR Carburetor w/ TPS x 1
Engine Cooling Liquid cooling
Engine Fuel Unleaded gasoline of at least PON 91/RON 95 rating, containing < 15% MTBE (Methyl Tertiary Butyl Ether)/TAME/ETBE, < 10% ethanol, or < 5% methanol w/ cosolvents & corrosion inhibitors
Fuel Capacity 12 L/3.2 US gal (1.9 L/0.5 US gal, reserve) 11.7 L/3.1 US gal (2.9 L/0.8 US gal, reserve) 10.3 L/2.7 US gal (3 L/0.8 US gal, reserve)
Bore x Stroke Ratio 94×64.8 mm (3.70 x 2.55 in) 96 x 62.1 mm (3.78 x 2.44 in)
Compression Ratio 10.5:1 12.0:1
Starting System Electric/kick Electric starter motor
Displacement 449.4 cm³ / 27.42 in³
Maximum Power 41 hp/41.6 PS (30.6 kW) @ 7,550 RPM
Top Speed 74 mph (119.1 km/h) – marketed
Air Filtration Oiled urethane foam
Lubrication Forced lubrication (twin wet sump)
Engine Oil & Quantity 0.82 L (0.87 US quarts) of SAE 5W-30 or 10W-40 Pro Honda GN4 HP4 4-sroke oil or its equivalent (w/out molybdenum additives & “Energy Conserving” labels) Options: 10W-30, 20W-40, 20W-50 w/ API grade of SJ meeting JASO T903 MA or MB 0.69 L (0.73 US quarts) of SAE 5W-30 or 10W-40 Pro Honda GN4 HP4 4-sroke oil or its equivalent (w/out molybdenum additives & “Energy Conserving” labels) Options: 10W-30, 20W-40, 20W-50 w/ API grade of SJ meeting JASO T903 MA or MB

Performing a proper carb cleanout is just as important as jetting adjustments on your quad. Check out this video by Mudline Motorsports that shows you how:

Drivetrain

The TRX450R uses a five-speed manual transmission and an automatic clutch system handled by a 520 O-ring chain.

This powertrain combo, coupled with a lower riding position, improved exhaust system, and new cylinder head porting features with lightweight Nikasil lining, makes the TRX450R racing and trail-friendly.

Additionally, CRF-style handlebar grips, clutch, and front brake lever lend to the four-wheeler’s superb handling and maneuverability.

2004 – 2005 Honda TRX450R Post-’05 TRX450R,
’07-’09 TRX450R-ER
Clutch Wet, multi-plate type
Transmission Type 5-speed, constant mesh (cable operated)
Gearshift Pattern Left-foot-operated return system (1-N-2-3-4-5)
Drive System O-ring sealed chain drive & OHC w/ rocker arm, RK520SMOZ10S/94 links – 25-30 mm (drive chain slack: 1-1 7/16 in) O-ring sealed chain drive & OHC w/ rocker arm, RK520SMOZ10S/96 links – 25-30 mm (drive chain slack: 1-1 7/16 in)
Primary Ratio 2.739 (63/23)
Final Drive Ratio 2.714 (38/14) 2.923 (38/13)
Transmission Gear Ratio 1st – 2.071 (29/14)
2nd – 1.625 (26/16)
3rd – 1.333 (24/18)
4th – 1.120 (28/25)
5th – 0.963 (26/27)
1st – 2.230 (29/13)
2nd – 1.785 (25/14)
3rd – 1.437 (23/16)
4th – 1.181 (26/22)
5th – 0.962 (26/27)

Ignition

The debut version of the SporTrax initially had separate electric-start and kick-start trims, which was later offered together for its 2007 Honda TRX 450R until more recent models.

The battery format required for the 4×4 is a YTZ7S (view on Amazon) format – typically high-performance and maintenance-free. When servicing, you will find the battery located in a compartment under the left rear fender.

2004 – 2005 Honda TRX450R Post-’05 TRX450R,
’07-’09 TRX450R-ER
Ignition AC-CDI (Capacitor Discharge Ignition) w/ electronic advance
Ignition Timing 12° BTDC @ 1,600 RPM 12° BTDC @ 1,700 RPM
Spark Plug, Gap NGK IFRH811, DENSO VK24PRZ11, (1.0-1.1 mm, 0.039-0.043 in)
High-speed riding: NGK IFRH911, DENSO VK27PRZ11, (1.0-1.1 mm, 0.039-0.043 in)
NGK IFR7L11, DENSO VK22PRZ11, (1.0-1.1 mm, 0.039-0.043 in)
High-speed riding: NGK IFRH811, DENSO VK24PRZ11, (1.0-1.1 mm, 0.039-0.043 in)
Alternator Type Triple-phase A.C. generator
Rated Output 200 W @ 5,000 RPM 214 W @ 5,000 RPM
Fuse 15 Amp
Battery 12V (6 Ah), YTZ7S formats
Battery Dimensions (L x W x H) 4.50×2.81×4.21 in (114 x 71 x 107 mm)

Tires

Aluminum wheels are fitted with Dunlop radial tires that provide maximum grip and cornering ability. These tires are durable but should not go beyond the range of 23.44 kPa (0.24 kgf/cm2, 3.4 psi) to 36.54 kPa (0.37 kgf/cm2, 5.3 psi) when being aired down or inflated.

Stock rubber is perfect for occasional trail riding. But you may want to go for ITP Holeshot 6-ply GNCC Off-Road Bias Tires (view on Amazon) for dedicated wooded trail rigs and rock-crawling applications.

2004 – 2005 Honda TRX450R Post-’05 TRX450R,
’07-’09 TRX450R-ER
Front Tire, off-road/road air pressure Dunlop® KT371 AT22 x 7-10
27.58 kPa (0.28 kgf/cm2, 4 psi)
Dunlop® KT331H AT21 x 7-10
27.58 kPa (0.28 kgf/cm2, 4 psi)
Rear Tire, off-road/road air pressure Dunlop® KT335H AT20 x 10-9
32.40 kPa (0.33 kgf/cm2, 4.7 psi)
Dunlop® KT335H AT20 x 10-9
32.40 kPa (0.33 kgf/cm2, 4.7 psi)
Front Rim Size 10 x 5.5 AT
Rear Rim Size 9 x 8.0 AT
Front Brake Type Dual hydraulic 174-mm discs w/ twin-piston calipers
Rear Brake Type Hydraulic 190-mm disc w/ single-piston caliper

Suspension

Honda TRX450R parts such as removable aluminum subframe, aluminum rear grabrail, front bumper, rear-facing front suspension reservoirs, and aluminum front-and-rear brake calipers and brackets make the vehicle lightweight and durable.

Furthermore, the SporTrax generous front and wheel travel offer good bump absorption and provide faster damping response and improved vehicle performance at higher velocities.

2004 – 2005 Honda TRX450R Post-’05 TRX450R,
’07-’09 TRX450R-ER
Frame Type Tubular, double-cradle
Caster, Trail 5.87°, 25.58 mm (1.007 in) 5°, 23 mm (0.90 in)
Front Suspension Type, Travel Independent double-wishbone w/ Showa shocks (adjustable spring preload, rebound & compression damping), 213 mm (8.4 in) Independent double-wishbone w/ Showa shocks (adjustable spring preload, rebound & compression damping), 215 mm (8.5 in)
Rear Suspension Type, Travel Pro-Link® w/ single Showa shock (adjustable spring preload, rebound & compression damping), 230 mm (9.1 in) Pro-Link® w/ single Showa shock (adjustable spring preload, rebound & compression damping), 237 mm (9.3 in)
Red 2005 Honda TRX450R ATV

Dimensions

Overall dimensions of the Honda TRX450R slightly improved, although the width and maximum weight capacity remained unchanged. This almost-negligible increase in bulk is impressive, given the engine overhaul done and protective equipment added to the SporTrax beginning in 2006.

2004 – 2005 Honda TRX450R Post-’05 TRX450R,
’07-’09 TRX450R-ER
Length 1,846 mm (72.6 in) 1,862 mm (73.3 in)
Width 1,177 mm (46.3 in)
Height 1,108 mm (43.6 in) 1,100 mm (43.3 in)
Seat Height (Unloaded) 829 mm (32.6 in) 833 mm (32.8 in)
Ground Clearance 114 mm (4.5 in) 111 mm (4.4 in)
Wheelbase 1,251 mm (49.2 in) 1,275 mm (50.2 in)
Track (F/R) 937 mm (36.8 in) / 920 mm (36.2 in) 920 mm (36.2 in) / 833 mm (32.8 in)
Curb Weight
159 Kg (350 lbs) – dry
176 Kg (388 lbs)
162 Kg (357 lbs) – dry
178 Kg (392 lbs)
Maximum Weight Capacity 110 Kg (243 lbs)

Exterior

The Honda TRX 450R is generality bulletproof – with its aggressive styling and reliable components.

If there is one aspect where it needs improvement, it is in instrumentation. It has the basic clutch, brake, and engine controls and switches. But sadly, the SporTrax does not have a speedo, odometer, or even an oil temperature switch.

If you want to take note of your mileage, hours, and speed rating, you will need to get a Trail Tech 752-121 Black Vapor Digital Speedometer Gauge Kit (view on Amazon) as an accessory – it will be worth it!

2004 – 2005 Honda TRX450R Post-’05 TRX450R,
’07-’09 TRX450R-ER
Indicator Lamps Standard
Fuel Gauge Standard
Engine Stop Switch Standard
Headlight Hi/Low beam, 12V 30W/30W x 2
Brake Light/Taillight LED 12V 21W/5W
Indicator Lights 12V 3.4 W (coolant temperature) 12V, 3 W (coolant temperature, neutral)
Colors Red, Black Red, White, Black/Flame, Black/Blue, White/Orange, White/Red

Improvements Post-2006

Red 2013 Honda TRX450R ATV

Enhancements done to the Honda TRX450R can be divided into two episodes. The initial slew of improvements targeted more of the vehicle’s engine, mechanical components, and power output.

On the other hand, the second batch of developments was more cosmetic in nature. Here is a non-exhaustive rundown of changes the Honda TRX 450R underwent during its 11-year production run:

2006

  • There was a 96 mm bore increase and a 62 mm stroke decrease.
  • Electric and kick start models were added.
  • Engine compression went from 10.5:1 to 12:1 for the 2nd generation engine.
  • The SporTrax® included a more aggressive cam profile, an all-new, short skirt (forged slipper) piston, and titanium valves.
  • Honda changed the carburetor from a round-slide 42-mm Keihin to a flat-slide 40-mm FCR type.
  • Transmission ratios have been lowered and better designed for racing applications and trail use.
  • Maximum engine RPM increased from 9,800 to 9,850 – although some online sources point to a redline RPM of 10,500 stock and horsepower of only 38 hp (28.34 kW) instead of the marketed figure of 41 hp.
  • An extended swingarm and a new linkage ratio helped reduce the bucking issue of previous models.
  • An 8-mm decrease in the four-wheeler’s riding position lent to an improved center-of-gravity and handling.
  • Rear suspension travel improved from 9 inches (230 mm) to 9.3 inches (240 mm).

2007 to 2014

  • The style and reposition of the auto decompression feature and the inclusion of an electric starter for some trims provide excellent cold-starting and hot-starting operation.
  • Honda introduced new White and Black/Flame colors on the electric-start versions of the 2007 TRX450R.
  • New White with Orange frame color is made available for the 2009 TRX450ER models.
  • New Black/Blue body panels join White ones on the electric-start trims.
  • Black rims became an option with Orange Frame/White plastics.
  • Reflectors were upgraded for improved visibility and distinctive appearance.
  • Retro-inspired Special Edition trims were made available in the last two years of the Honda TRX450R.
  • HRC Power-Up Kit and ATV Trailerable Cover were made available through dealerships at the point of sale.

While a fuel-injected 2018 Honda TRX450R had been rumored for release as early as 2009, the said trim sadly never made it to production. The last model produced under the SporTrax lineup was the 2014 Honda TRX450R. It did have all the above engine and cosmetic enhancements – although avid Honda followers hoped for an easier-to-handle, faster, and more reliable version.

For satisfied owners, however, these shortcomings were negligible. In their eyes, the vehicle’s praiseworthy traits are all that mattered. This video by HNpowersports perfectly captures these strong points:

Honda TRX450R Price

Listed prices on Craigslist and other auction sites fall between $1,400 and $9,500, with 2005 TRX450R models having the heftiest price tag. You can find most of these near-stock units in Oregon, California, and other neighboring states within the region.

Typically, four-wheelers in mint condition would cost at least $5,000, with anything cheaper sold as whole units with minor cosmetic damage or some top-end work needed.

As for the lineup’s original MSRP, I went ahead and consolidated the information in the table below (Note that there are no available list prices for ’10 and ’11 models, and list prices for Special-Edition trims are assumed values):

Year – Trim – Model Number
**R – Kick-Start; ER/ERF – Electric-Start
List PriceRetail/Trade-In Values
2004 Honda TRX450R4$6,499$1,940 – $2,990
2005 Honda TRX450R5$6,499$2,110 – $3,170
2006 Honda TRX450R6$6,649$2,260 – $3,350
2006 Honda TRX450ER6$6,799$2,325 – $3,480
2007 Honda TRX450R7$6,749$2,415 – $3,570
2007 Honda TRX450ER7$6,899$2,430 – $3,710
2007 Honda TRX450ERF7$7,049$2,485 – $3,270
2008 Honda TRX450R8$6,849$2,515 – $3,790
2008 Honda TRX450ER8$6,999$2,540 – $3,955
2008 Honda TRX450ERF8$7,149$2,590 – $3,410
2009 Honda TRX450R9$7,499$2,725 – $4,000
2009 Honda TRX450ER9$7,649$2,785 – $4,195
2012 Honda TRX450R$7,999$3,360 – $4,485
2013 Honda TRX450R$7,799$3,540 – $5,150
2013 Honda TRX450R, Special Edition Tri-ColorN.A$3,725 – $5,410
2014 Honda TRX450R$7,799$3,795 – $5,510
2014 Honda TRX450R, Special Edition Tri-ColorN.A$4,000 – $5,810

About Honda

An institution in the ATV landscape, the Honda Motor Company Ltd., is one of the world’s most successful automotive manufacturers. Founded in 1946, the Japanese company traces back its roots to race cars, piston rings, and automation of military aircraft propellers.

From building and selling automotive parts and motorized bicycles with surplus engines, the maker of the Honda TRX450R eventually transitioned into other industries.

Today, Honda is recognized worldwide for pioneering innovations in electric automobiles, energy solutions, and motorsport vehicles.

Conclusion – Honda TRX450R Review

With barely any component shared with either the 400EX or the CRF450, the Honda TRX450R is still a force in the racing arena. Its Baja-proven durability is not only a testament to its impeccable record on the tracks but also makes it a perfect recreational ride.

The capabilities of this 2-stroke machine are so encompassing that it cannot be confined to just ripping through the dunes and dirt roads. A vehicle instrumental to the development of current racing mechanics, the TRX450R is unquestionable proof that a machine need not have fancy instrumentation, expensive add-ons, or EFI to offer an enjoyable ride and beat the crap out of its counterparts.

Kris Peter

Adventure seeker and off-road enthusiast. I love the thrill of going off-road and taking on the elements.

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