Cycle News - Archive Issues - 1970's

is remark ably trim at case level thanks to the jacksh aft Despit e the inevita ble width of a six cylinde r motor. the CBX CBX's cranks haft. The width - just over 23" - is only driven alterna tor and transis torized ignitio n set behind the two inches wider than a CB750. 8 the cranksh aft. On the left side. the j ackshaf t spins the alterna tor through an all -metal, two-pla ted clutch (which cushion s the alterna tor from the shock of the six's violent acceler ation and deceler ation at higher rpm). On the right side, the jacksha ft carries the ign iti on timing system and starter motor gear, and feeds the cranksh aft power to the clutch. Becaus e the cranks haft center is much higher than th e bottom of a con ven tional, end-of -cr-ank shaft mounte d alterna tor cover, the CBX has more useful clearan ce than its actual widt h would im p ly. T o enhance that clearan ce . the cr a n ksh aft counter weights for th e two outside cylind ers have been pared down , 'a nd th e cra nkcases beveled . Becaus e the six has more eve n cylinde r firing , the Honda uses sm aller muffler s than require d by a 1000 cc four . The CBX's muffler s are tu cked in an close as possibl e and point • upward in the rear. The result is that the CBX can be leaned over farther in a tu rn withou t scrapin g - 41 0 - than a ny ot he r any from bike st r ee t large manufa cturer. The new Honda six has more corneri ng clearance than any la rge d isplace ment It al ian , British , Germa n or Japane se m otorcyc le cu rr ently offered for sale. With th e center and side stands attache d , the CBX scra ped at only one place on the twist y Willow Springs road course: at th e apex of the banked , downhi ll , left hand turn which m arks the co nclusio n uphilt -downh ill track 's of the horsesh oe. Even then , only the sidestan d touched down , briefly a nd non -threa ten ingly. That's with street tires. Ra cing slicks a llow a greater lean angle , and it remain s to be seen if the CBX ha s enough corneri ng clea rance for serious road ra cing. But th e CBX wasn 't designe d to be a serious road racer. In fact , Irimaji ri made major design concess ions to improv e the six 's st reetabi lit y. The bank of six carbur etors origina lly splayed the rider's knees outwar d , an awkw ard sea ting position . Norimo to Otsuka , the man in charge of styling expo rt· m arket Honda s , convin ced Irimaji ri t ha t more rider knee room had to be provide d . Respon ding to that need , Irimaji ri made the six narrow er at the seat/ta nk junctio n area b y tilting th e engine forward 33 d egrees , and by d esignin g angled manifo lds for the outside four carbure tors. The resultan t carbure tor assemb ly is V-sha ped, and the intake manifo lds are uneven in length. Irimaji ri used plenum s extende d into the air box to even up the intake tract lengths . Thus, the distanc e from the air box to the cylinde r is equal in each case - just the d istribut ion of that length a hea d of or behind each carbure tor varies. But because the angle of the two ou tside intake manifo lds is so great, th e outboa rd intake valves for cylinde rs one and six actually flow no air. The great angle sends all the m ixture throug h the inside intake valves 'of those cylinders.vTo make ilie machin e more comfor table on the street, some engine efficien cy was sacrific ed. A month after it was first seen at Willow Spring s , the CBX finally landed in its intende d en vironm ent the street. For three sh ort days magazi ne staffers rode the six around Southe rn Califor nia . is GLIOOO the Because manufa ctured and sold as a tourer, th e CBX is unencu mbered by any need to b e a comfor t ab le freewa y flyer. Instead , the CBX is a sport bike for sp irited riding on public roadwa ys. And once freed from the singlem indedness of the racetra ck, the CBX functio ns quite well . Sample d on the street, the engine is still smooth and torquey , the exhaus t note still snarly, the transmi ssion and clutch and brakes still ideal. And when ridden below 100 mph , the CBX does someth ing it couldn 't quite achieve on the racetra ck - it handles . Even run hard throug h snakin g mounta in canyon s, the six flicks from side -to-side with an agility and precisi on which seem t o belie its weight. It won 't wobble or flex or wander around a high-sp eed street turn . The street and the racetra ck are two differen t worlds, and the six is two differe nt motorc ycles , depend ing upon where it is ridden . The CBX handles better and easier than the XSll or Zl ·R, but noticea bly less surely than the GSIOOO . On th e freeway , the CBX is still firm too firm and taut. and taut Concre te highwa y expans ion joints send shocks to the rider through the still suspens ion, and th e seat become s uncom fortabl e quickly . But the seating position itself is perfect . the relation ship betwee n the handleb ars and the footpeg s and the seat rea ching that elusive balanc e which no manufa cturer before has been able to . find . When the throttle is opened up in fifth gear from a cruising speed of 60 or 65 mph (abou t 4500 to 5000 rpm), th e exha ust note sounds terrific . But the motorc ycle doesn't lu nge forward with author it y like the XSII or GSlOOO . The six moves out, to be sure, but dazzles no one. It isn't until 6500 rpm th a t things begin to happen , but a t that point, all hell breaks loose . The sam e is true off the highwa y. on cit y streets. Roll on the gas below 6500 and nothing much happen s. But twist th e revs up to 6500 or 7000 a nd drop the clutch, and the front wheel paws for the sky as the rear wheel spins and sm okes. Shiftin g into second at the redline brings up the front wh eel again as the mad rush of acceler ation continu es and other vehicles fade from view in the twin mirrors . An XSll or GSlOOO will kill the CB X in a top-gea r roll-on from highwa y speeds, but the six will leave both the Yamah a and the Suzuki far behind in an all -out drag race. The CBX's burst of top end speed must be experie nced to be believe d. Steppin g off the .six and jumpin g onto any other motorc ycle impress es the rider with this fact: th e CBX has no slack, or slop , or softness. It feels , in all street situatio ns, very firm and precise . Someh ow the CBX makes everyth ing else feel . . .lo ose and disjoint ed, crud e and unfinis hed. How much of this feeling of increai ble precisio n is due to the fact that this six . is a prototy pe is impossi ble to say. But if produc tion model CBX Hondas can captur e that same feel , then everyth ing else is finished , and the CBX will reign as the ultimat e trip for a street motorcy clist. Not just the feel is differen t. Even the instrum ents and controls on the CBX are striking in their differen ce. They carry on the designe r's obsessio n

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