REVIVING HONDA’S “OLD PIG” AS REDMOTO LAUNCHES CRF450XR

Honda’s XR models are the stuff of legend and still widely used around the world. As one of the original dual-purpose motorcycles, they’ve been used to race Dakar, transport medicines across Africa, help farmers chase sheep across Australia, navigate the earth, trail ride for days and race enduro in equal measure.

Based on the 2019 CRF450RX, the new XR model from Italian tuning house, race team and Honda dealer Redmoto, has all-round usefulness at heart with an engine developed to comply with the Euro4 regulations, be mechanically durable and equally useable with the “ideal mix of power and character.”

With the promise to blend the CRF450RX and L models  and with those big XR graphics on the side, our ears were pricked up by Redmoto’s latest offering for 2019

 

  • First main service at 30,000km
  • 43hp – full power model
  • Termignoni exhaust
  • Complies with EURO 4
  • Larger radiators with fan
  • Road use approved
  • Electric starter
  • Crankshaft with greater inertia
  • Six-speed gearbox
  • 7.6 litre fuel tank
  • LED lighting system
  • CRF450RX model derived

Engine changes

The standard CRF 449cc engine in the CRF450XR has undergone plenty of work by the technicians at RedMoto – though many of the details appear to be the same as the 450L. Redmoto say the fundamental architecture of the four-valve, Unicam engine has remained unchanged from the 450RX model, with details modified to support the XR’s outlook: the remit being to produce an engine which is more reliable and usable for different riders, in different situations, both on the road and off-road.

Arguably the most important points are the reliability and the maintenance intervals: 30,000km between the major services, they say but with oil and filter changes still recommended every 1,000KM. These details match the CRF450L and point to the L being the doner for the XR’s base engine.

Again, like the 450L, the bore and stroke are unchanged compared to the CRF450R (96 x 62.1mm) but the piston has three rings instead of one for longer life. The compression ratio is 12.0: 1 (compared to 13.5:1) for better user-friendly feel. Crankshaft mass is been increased for similar reasons, more than 13% for improved torque and traction, plus ignition timing is revised for a wider and more uniform power delivery. The generator has increased capacity to provide the power required by LED lights and to maintain the battery charge (the battery itself is a high capacity unit).

The gearbox too is six-speed instead of five on the stock CRF450R, to provide a wider ratio and make road use more comfortable. Final drive is 13 front and 51 tooth rear sprockets. The airbox is identical to that of the RX and supplies the PGM-FI system with a lambda probe on the single exhaust developed by RedMoto in collaboration with Termignoni.

The four-valve Unicam head is equipped with a finger-operated rocker arm on the intake valves. The lift of the intake valves is 7.7mm, for those of discharge it is 6.7mm. The diameter of the intake valve is 38mm. The valve springs have an oval cross section and the angle between the intake valves is 9°, between the exhaust valves is 10.5°.

The clutch has seven friction plates with a 2mm pressure plate for effective heat dissipation; the springs have the ideal load to determine an adequate and consistent connection to the power supplied, which in the XR version is equal to 43HP (full power kit version).

Overall the style of the CRF450XR draws from the CRF450RX but reading between the lines and looking at the spec, the dual-sport CRF450L model is hiding behind that XR graphic. Honda’s development of that L engine to stretch out 30,000km service intervals is the giveaway here.

That said clearly the power hike to 43hp in full power spec is a boost on the L model’s softer motor. The XR benefits also from having the RX’s more useful off road 140 rear tyre and higher spec suspension which will pitch it right in there as a very capable off-roader.

Whether you look at it as a better performing CRF450L with more power or a more user-friendly CRF450RX, Redmoto’s new XR 450 is a blast from the past revisited with bang-up-to-date components.

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