Also known as the
Interceptor, is a
motorcycle introduced by
Honda in 1998. It is a successor to the
VFR750F (1986–1997), which was preceded by the
VF750.
From its first sales in 1986, the VFR750F scored highly on many press
reviews. While it was originally intended to be a sports bike, the
introduction of lighter competitors (including the nearly 30 kg/66 lb
lighter
GSX-R750) prompted Honda in 1990 to transition the VFR into a mid-sized
sport touring bike, a category of which the VFR became the de facto
benchmark. However, by 1997,
Triumph and
Ducati presented Honda with significant sports-touring competition, so Honda responded with a redesigned VFR800 in 1998.
Fifth Generation
1998 Honda VFR800 (5th generation).
Rather than being a direct development of the previous carbureted
VFR750F engine, the VFR800 engine was a detuned and longer-stroke power
plant based on the fuel-injected
RC45 race engine. The
RVF750R RC45 engine, although a development of the
VFR750R RC30 and originally derived from the
VFR750F RC24, was very different as the gear drive to the cams was moved from the centre of the engine to the one side, similar to the
CBR250.
Tuned for road use in the VFR800, fuel injection provided excellent
driveability and power was slightly increased over the VFR750. The most
noticeable change, however, was that the
torque figures were substantially improved from the previous model right up to the 11,750 rpm
red line. All VFR800 models use
fuel injection instead of
carburetors for fuel-air mixing. In 2000, Honda updated the fifth generation VFR (RC46) with a
catalytic converter,
oxygen sensors, and an
EFI system that would enter closed-loop mode under highway (cruising) operation.
The VFR800 bodywork covered a frame derived from the
VTR1000 Firestorm. It incorporates the VFR trademark
single-sided swingarm pivoted from the aft of the
crankcase, using the engine as a stressed member of the frame.
Honda fitted its DCBS
linked braking system, a departure from traditional independent front/rear motorcycle
braking systems. In this system, the front brake lever applies pressure to four (in later models five) of the six front
pistons.
The rotational movement of the left caliper when engaged actuates a
secondary master cylinder and applies pressure to one of the rear
pistons. The rear brake pedal is directly attached to the remaining
pistons (two in the rear, and one or two in the front).
Sixth Generation
The sixth generation VFR (for the first time marketed only as the
"Interceptor" in the USA) was introduced in 2002. For the first time it
featured dual underseat exhausts, an optional
anti-lock braking system
(ABS) in addition to the DCBS, and optional hard luggage. It featured
chain-driven cams rather than the traditional VFR gear-driven cams, and
was the first motorcycle to have Honda's VTEC valve-actuation
technology. The implementation of VTEC was seen as a bid by Honda to
meet tightening noise and
emissions standards in Japan and abroad while improving the peak horsepower of the engine. Similar to the automotive version of
VTEC-E
the simplified motorcycle version of VTEC employs only two of the four
valves per cylinder when operating at lower engine speeds. All four
valves per cylinder were engaged above 6,800 rpm. This is initiated by
an electronically actuated oil spool valve, which send oil pressure to
the lifter actuators, which then move the engagement pins into place
above the valve stem, allowing the remaining two valves to open. This
design allows for variable valve timing as well, since the cam lobe
profiles could be made different. It is speculated that the duration of
valve lift and overlap on the below and above 6,800 RPM valves differ.
After some criticism of the abruptness of power transition, Honda
lowered the VTEC activation rpm threshold to 6,400 rpm in 2006. The VTEC
disengages two cylinder valves when the engine speed drops again below
6,100 rpm. For 2009, there were no significant changes to the VFR800.
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