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Honda CRF450RX 2018

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Cross Country / Hare Scramble / Racing

2018 Honda CRF450RX

450cc

4-stroke

52.7hp

Measured power

257lb

Curb weight

37.8in

Seat height

12in

Front travel

2018 Honda CRF450RX overview

The 2018 Honda CRF450RX is Honda's closed-course off-road racer: the CRF450R motocross bike adapted for cross-country, GNCC-style and hare scramble racing, with its own ECU map and suspension settings, an 18-inch rear wheel, Dunlop AT81 tires (90/90-21 front), an aluminum sidestand and a bigger 2.25-gallon fuel tank. Its fuel-injected, liquid-cooled 450cc single has a Unicam SOHC four-valve head, electric start and a five-speed gearbox with a cable-operated clutch, plus a handlebar map switch. For 2018 the kickstarter was dropped and a lighter lithium-ion battery fitted.

Who it's for

For experienced riders who race cross-country, GNCC-style and hare scramble events on closed courses and want a 450 four-stroke set up for woods and rough terrain rather than a motocross track. It is a competition-only bike: not street legal in the US, and not meant for beginners.

Quick facts

  • The 2018 Honda CRF450RX has a 450cc fuel-injected 4-stroke engine, a 5-speed gearbox and electric start.
  • The 2018 CRF450RX weighs 257 lb ready to ride and has a 37.8 in seat height.
  • The 2018 CRF450RX runs 90/90-21 front and 120/90-18 rear tires.
  • The 2018 CRF450RX takes 1.1 US qt (1.0 L) of 10W-30 engine oil; change it every 4 races or about 15 hours.
  • The 2018 CRF450RX lists at $9,249 (US MSRP). It is not street legal in the US.

2018 Honda CRF450RX specifications

Engine

Displacement
450cc
Stroke
4-stroke
Fuel system
Fuel injection
Bore × stroke
96 × 62.1 mm
Compression
13.5:1
Power (measured)
52.7 hp at the rear wheel
Cooling
Liquid
Configuration
Single-cylinder
Valve train
SOHC
Valves
4
Engine oil
1.1 US qt (1.0 L)
Oil type
10W-30
Coolant
1.1 US qt (1.07 L)

Clutch

Type
Wet multiplate
Actuation
Cable

Drivetrain

Starting
Electric
Transmission
5-speed
Chain size
520
Chain links
114
Front sprocket
13T
Rear sprocket
50T

Dimensions

Seat height
37.8″
Ground clearance
12.9″
Wheelbase
58.1″
Width
32.6″
Height
50.2″
Length
85.6″
Curb weight
257 lb
Fuel capacity
2.25 gal

Price & warranty

Colors
Red

Equipment

Sidestand
Standard

Frame & steering

Frame material
Aluminum
Rake
27.4°
Trail
4.6″

Suspension

Front
49 mm inverted Showa coil-spring fork
Front travel
12″
Rear
Pro-Link Showa single shock
Rear travel
12.3″

Wheels & tires

Front wheel
21″
Rear wheel
18″
Front tire
Dunlop AT81F 90/90-21 54M
Rear tire
Dunlop AT81 120/90-18 65M

Brakes

Front disc
260 mm
Rear disc
240 mm

Stock features

Map switch
Yes
Skid plate
Yes
Street legal (US)
No

Battery / electrical

Battery
Yes
OEM battery
HY85S
Chemistry
Lithium
Voltage
12V
Capacity
2 Ah

2018 Honda CRF450RX maintenance

From the maker's manuals. Tap a row to see the manual page.

Service intervals

Change engine oil
Every 4 races or about 15 hours
Replace oil filter
Every 4 races or about 15 hours
Clean air filter
Every race or about 3.5 hours
Inspect spark plug
Every race or about 3.5 hours
Change engine oil (first time)
After the first break-in ride
Replace oil filter (first time)
After the first break-in ride

Spark plug

Spark plug
NGK SILMAR9A-9S
Plug gap
0.031 – 0.035 in (0.80 – 0.90 mm)
Spark plug (optional)
NGK SILMAR10A-9S

Torque specs

Oil drain bolt
13 ft‑lb (18 N·m, 1.8 kgf·m)
Oil filter cover bolts
7.4 ft‑lb (10 N·m, 1.0 kgf·m)
Front axle nut
65 ft‑lb (88 N·m, 9.0 kgf·m)
Front axle pinch bolts
15 ft‑lb (20 N·m, 2.0 kgf·m)
Rear axle nut
94 ft‑lb (128 N·m, 13.1 kgf·m)
Upper triple clamp bolts
16 ft‑lb (22 N·m, 2.2 kgf·m)
Lower triple clamp bolts
15 ft‑lb (20 N·m, 2.0 kgf·m)
Steering stem nut
80 ft‑lb (108 N·m, 11.0 kgf·m)
Handlebar clamp bolts
16 ft‑lb (22 N·m, 2.2 kgf·m)
Front brake caliper mounting bolts
22 ft‑lb (30 N·m, 3.1 kgf·m)
Front brake disc nuts
12 ft‑lb (16 N·m, 1.6 kgf·m)
Rear brake disc nuts
12 ft‑lb (16 N·m, 1.6 kgf·m)
Rear sprocket nuts
24 ft‑lb (32 N·m, 3.3 kgf·m)
Front sprocket bolt
23 ft‑lb (31 N·m, 3.2 kgf·m)
Chain adjuster locknut
20 ft‑lb (27 N·m, 2.8 kgf·m)
Shock absorber mounting bolts
32 ft‑lb (44 N·m, 4.5 kgf·m)
Coolant drain bolt
7.4 ft‑lb (10 N·m, 1.0 kgf·m)

2018 Honda CRF450RX vs 2017

Of the specs below, the 2018 Honda CRF450RX is 4 lb lighter, has electric start (was electric and kick) and takes the 2 Ah HY85S battery (was the 3 Ah YTX4L-BS), compared with the 2017 model.

Spec20172018Changed
MSRP$9,249Same
Displacement450ccSame
Curb weight261 lb257 lbNew
Seat height37.8 inSame
Front travel12 inSame
Rear travel12.3 inSame
Fuel2.25 galSame
Gearbox5-speedSame
Front tireDunlop AT81F 90/90-21 54MSame
Rear tireDunlop AT81 120/90-18 65MSame
StartElectric and kickElectricNew
Battery3 Ah YTX4L-BS2 Ah HY85SNew

2018 Honda CRF450RX photos

Honda CRF450RX FAQ

  1. How much power does the 2018 Honda CRF450RX make?

    Cycle World measured 52.7 hp on its dyno.

  2. What engine does the 2018 Honda CRF450RX have?

    A fuel-injected, liquid-cooled 450cc single-cylinder four-stroke with a Unicam SOHC four-valve head and a five-speed gearbox.

  3. How is the 2018 Honda CRF450RX different from the CRF450R?

    It has its own ECU map and off-road suspension settings, a 90/90-21 front tire and an 18-inch rear wheel with Dunlop AT81 tires (the CRF450R runs an 80/100-21 front and a 19-inch rear). It also has an aluminum sidestand and a bigger 2.25-gallon fuel tank.

  4. What is the seat height of the 2018 Honda CRF450RX?

    37.8 in.

  5. How much does the 2018 Honda CRF450RX weigh?

    Honda lists a curb weight of 257 lb, ready to ride with a full tank.

  6. How much suspension travel does the 2018 Honda CRF450RX have?

    12.0 in at the front and 12.3 in at the rear.

  7. How much fuel does the 2018 Honda CRF450RX hold?

    2.25 US gal (8.5 L).

  8. What oil does the 2018 Honda CRF450RX take?

    SAE 10W-30 motorcycle oil (JASO MA), 1.1 US qt (1.0 L) after draining.

  9. Is the 2018 Honda CRF450RX street legal?

    No. It is sold for closed-course competition only and is not street legal in the US.

  10. What was the MSRP of the 2018 Honda CRF450RX?

    $9,249.

  11. What size tires does the 2018 Honda CRF450RX use?

    90/90-21 front and 120/90-18 rear.

  12. What spark plug does the 2018 Honda CRF450RX take?

    NGK SILMAR9A-9S, gapped 0.031 – 0.035 in (0.80 – 0.90 mm).

  13. What chain and sprockets does the 2018 Honda CRF450RX use?

    A 520 chain with 114 links on a 13-tooth front and 50-tooth rear sprocket.

  14. Is the 2018 Honda CRF450RX different from the 2017 model?

    Among the main specs, the 2018 Honda CRF450RX is 4 lb lighter, has electric start (was electric and kick) and takes the 2 Ah HY85S battery (was the 3 Ah YTX4L-BS), compared with the 2017 model.

Other Honda CRF450RX model years

Specs from Honda's owner's manual, Honda's website and published spec sheets. Updated .