7
edits
Difference between revisions of "Honda VFR800"
→Physical characteristics
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The new bodywork covered a frame derived from the [[Honda VTR1000|VTR1000 Firestorm]]. This incorporates the VFR trademark of a single-sided swing-arm [[Pivot|pivoted]] in the rear of the crankcase, thereby using the engine as a stressed member of the frame. Handling is described by some as impeccably neutral. | The new bodywork covered a frame derived from the [[Honda VTR1000|VTR1000 Firestorm]]. This incorporates the VFR trademark of a single-sided swing-arm [[Pivot|pivoted]] in the rear of the crankcase, thereby using the engine as a stressed member of the frame. Handling is described by some as impeccably neutral. | ||
The [[Brake|braking]] system departed from the normal front and rear independent arrangement and Honda fitted their DCBS | The [[Brake|braking]] system departed from the normal front and rear independent arrangement and Honda fitted their DCBS (dual-combined braking system). In this system, squeezing the front brake lever applies pressure to four of the six front [[piston]]s. The rotational movement of the left caliper, when braking, actuates a secondary master cylinder which applies pressure to one of the rear pistons. The rear brake pedal is directly attached to the remaining two rear pistons and two front pistons. This arrangement irritated some but was praised—in some circles at least—for removing [[fork dive]] under heavy braking. When Honda released a new generation of VFR in 2002, the DCBS was modified to be less "linked". With the new DCBS, the front brake lever now activates five of the six front pistons and the rear brake pedal activates the two rear pistons and only one front piston. The secondary master cylinder (which is actuated by the rotational force of the front left caliper under braking) remained unchanged continuing to activate one rear piston. | ||
Unlike its VFR predecessors, all VFR800 models use [[fuel injection]] instead of [[carburetor]]s for fuel-air mixing. In 2000, Honda updated the fifth generation VFR with a [[catalytic converter]], oxygen sensors and an EFI system that would enter closed-loop mode under highway (cruising) operation. | Unlike its VFR predecessors, all VFR800 models use [[fuel injection]] instead of [[carburetor]]s for fuel-air mixing. In 2000, Honda updated the fifth generation VFR with a [[catalytic converter]], oxygen sensors and an EFI system that would enter closed-loop mode under highway (cruising) operation. | ||
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The sixth generation (RC46) began in 2002 and featured dual underseat exhausts and available ABS (antilock brakes) in addition to the DCBS. It was the first generation of VFR to feature chain-driven rather than gear-driven cams plus VTEC valve actuation technology. In contrast to the automotive version of VTEC, where the cam timing is changed to suit the engine RPM providing a broad spread of power, the simplified [[motorcycle]] version employs only 2 of the 4 valves per cylinder when operating at lower engine speeds. All 4 valves per cylinder are utilised above 7000 rpm. These changes were a bid by Honda to meet tightening noise and emissions standards in their home market and abroad. In 2006, Honda has lowered the VTEC activation threshold as the power delivery of the 2002-2005 VTEC models tended to dip slightly before the transition point. In the 2006 edition the VTEC engages at 6400 rpm and stops working when the rpm is back to 6100. | The sixth generation (RC46) began in 2002 and featured dual underseat exhausts and available ABS (antilock brakes) in addition to the DCBS. It was the first generation of VFR to feature chain-driven rather than gear-driven cams plus VTEC valve actuation technology. In contrast to the automotive version of VTEC, where the cam timing is changed to suit the engine RPM providing a broad spread of power, the simplified [[motorcycle]] version employs only 2 of the 4 valves per cylinder when operating at lower engine speeds. All 4 valves per cylinder are utilised above 7000 rpm. These changes were a bid by Honda to meet tightening noise and emissions standards in their home market and abroad. In 2006, Honda has lowered the VTEC activation threshold as the power delivery of the 2002-2005 VTEC models tended to dip slightly before the transition point. In the 2006 edition the VTEC engages at 6400 rpm and stops working when the rpm is back to 6100. | ||
The sixth generation has some weaknesses too: The rectifier unit in early models was problematic and some electrical wiring was not thick enough to handle the currents of the headlight units. | The sixth generation has some weaknesses too: The rectifier unit in early models was problematic and some electrical wiring was not thick enough to handle the currents of the headlight units. The stator on early models were not powerful enough to keep the bike from dying in stop-and-go traffic; Honda had a service campaign to install more powerful stators on all effected units. The rear sub-frame on some early models was prone to cracking as well (this was fixed in a recall). The starter-valves need to be synchronised to achieve better engine stability. Also the wiring for the front and rear oxygen sensors was also backwards on some bikes that were sold in Europe. | ||
==1998== | ==1998== | ||