CBR Timeline -- The 954's family tree
When it was first introduced, the 1993 Honda CBR900RR set a staggering precedent for light weight that some manufacturers are still attempting to match. At 453 pounds with a full tank of gas, the 900 was just four pounds heavier than Honda's own CBR600F2, and a mind numbing 76 pounds lighter than the next-lightest open-class machine at the time, the Yamaha FZR1000. And although it finished a tick behind the FZR in SR's first open-class shootout, we raved that, "The 900 felt like a 600 from the seat but looked like a superbike from the dragstrip's timing tower." Minor changes to the '94 model included an improved shift drum to cure notchy shifting, and steadier mirrors.
In a move to refine the CBR's handling traits over bumpy pavement, the '95 model's suspension was upgraded with revised spring and damping rates, and a compression adjuster was added to the front fork. More aggressive bodywork incorporated a "cut reflector" design headlight and fewer of the CBR's unique fairing holes. Slimmer and firmer footpegs were patterned after the RC45, and a shift linkage replaced the original model's backward pedal. A new instrument panel included an electronic speedometer that measured speed from the countershaft sprocket. The only engine change in 1995 was the replacement of the aluminum valve cover with a magnesium piece.
In order to achieve "optimized balance of rigidity," Honda significantly altered the '96 CBR's chassis and suspension. The frame and swingarm were fabricated from larger, thinner-walled extrusions for reduced torsional rigidity. The fork and shock internals were re-designed, and the swingarm pivot raised by 5mm. Revised ergonomics brought the bars 10mm higher and swept back five degrees more than earlier models, along with a slimmer gas tank. Engine updates included a bump in displacement to 918cc via a 1mm bore increase, slightly higher compression, a curved radiator, larger muffler, extra clutch plates, smaller alternator, and the addition of a throttle position sensor. New graphics were the only change for 1997.
Continuing "subtle refinements" in the CBR's chassis saw frame stiffness closer to the original model's, revised suspension internals, and 5mm less triple clamp offset (an almost universal aftermarket upgrade to previous models). New brake calipers acted on larger front discs, the fairing was re-shaped and raised footpegs subtly changed ergonomics again. Eighty percent of the engine's internals were all-new to reduce weight and minimize friction; other updates included redesigned combustion chambers and porting, aluminum composite cylinders, new pistons, a smaller and lighter clutch pack, revised gearbox ratios, larger radiator, and a new stainless steel exhaust header.
A major revision for the open-class Honda resulted in the CBR929RR, aimed squarely for Yamaha's R1--which took Honda's original CBR concept further. A completely new engine incorporated fuel injection, more oversquare cylinder dimensions, larger valves set at a narrower included angle, lighter internals, and an all-titanium, HTEV-equipped exhaust system. The "pivotless" chassis had the swingarm mounted to the engine cases but incorporated a brace underneath the engine. Updated suspension and brakes included an inverted front fork and huge 330mm front discs; and, finally, the CBR's trademark 16-inch front wheel was ditched for a more common 17-inch hoop.