Cycle News - Archive Issues - 1980's

(Above) The U.S . ve rsio n of the 1986 VFR750F comes with a sid estand on ly, although there are centerstand lugs on the frame. European models have a centerstand. Exhaust head pipes are stainless steel, frame aluminum alloy. There's no fork brace under that front fender. (Below ) The VFR750F is vastly better than the VF750F it replaces, feeling much lighter and smaller. New lile lor the V-lour: Riding the VFR750F By John Ulrich ROSAMO ND , CA, FEB. 4 If p roduction-line models live up to th e promise of pre-production pilot bikes ridden by the press at Willow Springs Raceway, Honda's new VFR750F puts the company back in the h igh-performance 750cc sweeps takes . T he lat est In terceptor is far superior to the 1983 VF750F introduced in 1982 14 a nd g ives every in dica tion of being on a par with the Yamaha FZ750 and Suzuki GSX R750 in terms of racetrack performance. And even more important for street riders , the VF R750F 's racetrack per fo rm ance does not come at a cost of a severely cramped, uncomforta ble seating position; more than the Yama ha and the Suzuki, the Honda o ffers reasona ble rider co mfort at less-than -wideopen speeds. T he key is ho w close the VFR 750Fs you can buy la ter th is seaso n (the bikes ar e expected to reach Ll.S, dea ler showrooms in May) wi ll be to th e p ilot production ma chines. Pi lot produ ction motorcycl es, H onda spo kesme n exp lain, a re asse m bled as pan of the p roce ss of sett ing up th e regular assembl y lin e, and mayor ma y not be within normal production tolerances. They are not hand- VFR750F rocker arms pivot on balls with screw tappets; design reduces reciprocating mass and m ultiplies li ft at the cam lobe. built, pre-product ion prototypes , th e 1986 version deep en. In th e quest b ut th ey're not cranked out on a to reduce ove ra ll weight and to low er wi de-o pe n m ass-production lin e, fric tio na l losses ca used by rota ting ei ther. mass a nd reciprocating mass, Honda Furth er muddyin g th e wat ers is th e engi neers pa red weigh t from pi stons, fact th at th e majority of second -generpi ston rin gs (ma de th inner ), con necta rio n Interceptors im ported into th e ing rods (new hea t treating allowed th e rod s to be lighter), valves (with U. S. will actua lly be 698.7cc tariffbusting VFR 700Fs , not 748cc wai sted stems) , a nd val ve springs. VFR750Fs. A lim ited number of The biggest sing le change within VF R 750Fs will be imported , sold the cylinde r heads is to the rocker primarily Cor racing purposes, to arm s; th e first Interceptor used a void problems with rules prohibitCorked rock ers , each rocker activated ing altering stroke to reach class cc by a single cam lobe and actuating limits . Th e 700 and 750 have the the two intak e or the two exhaust same bore, 70mm, but the 700 has a valv es o f a given cylinder , with screw 45.4m m stroke vs. the 750's 48.6mm tappets a t th e end o f th e rockers pushstro ke. ing against the. valve stems and proEven so, th e VFR 750Fs that do vidi ng adjustment. The rockers pirea ch America wi ll be street-lega l in voted on shafts below the camshafts. a ll 50 sta tes, including Cal ifornia; a T he new roc kers each operate o ne California .versio n will co me with valve a nd have their ow n cam lobe; the evaporative em issions ca tch ca nthe roc kers pivo t on ba ll joints wit h nisters required by t h e sta te's lash adjustment scr ew s built into to ugher-than-federal emissions stanth e pivot, behind the camshaft. The dard. end of the rocker rides directly o n the Compared to th e previous Inter valve stem. The individua l rockers ceptors, the VFR750F is lighter a nd are ligh ter , with less weigh t movin g smaller, the result of a serious effort u p and down with the valves. Beto red uce the weight and size o f every cause o f the pivot placemen t, the component. The n ew machine is rockers multiply the Tift built into abo ut 57 p o u n d s ligh ter, with a the cam lobe, allowing sma ller lobes claimed dry weight of 436 po und s to produce the desired lift. In theory, compared to the older bike's 493 that may reduce camshaft weigh t, pounds, and has a wheelbase of 58.3 b u t the q u es t io n remains as to inches vs. the older Interceptor's 61.8 whether the new system, with twice inches . as many smaller ca m lobes and twice Those basic specifications p ut the as many lighter roc kers, is actually VFR750F far closer to the competilig hter overal l. tion, comparing the new Honda to The big gain from the gear-driven the GSX R75 0 Suzuki (388 pou nds camshaft system is in frictional losses dry , 57 .3-inch wheelbase ) a nd the (u p to 30%, th e engineers say) bu t the Yamaha FZ750 (46 1 pounds dr y, system is surely heavier than a stan58.5-inch wh eel base . da rd ca m chai n system. It uses four Like Yamaha a nd Suzuki, Honda gears to drive the engine's four camis claiming more th an 100 horseshafts, with two gears and their gear power fo r its la test high-performance holders in eac h cylinder ba nk. 750; in Honda's case , the figure is 104 - Not o n ly is the system of drivin g bhp at 10,500 rpm. Redl ine is 11,500 the camshafts changed, but th e valve from th e wa ter-cooled, double -overti mi ng is also altered to suit th e head- camsha ft, fo ur-va lves-per-cylVF R 750's 180° cra n ks ha ft, which inder, 90° V-four. L ike the ol de r Inspaces Ciri ng impu lses more even ly terceptor, th e VF R75 0F has a bore th a n th e origina l Int ercepto r's 360° a n d s tro ke o f 70x 48.6 mm a nd an cran ks haf t. Honda numbers th e Vfou r 's cyli n ders starti ng at th e left act ua l displ acem ent o f 10.5: I. Bu t th e VFR 750F has gear-driven camsha fts rear cylin der (o ne) fo llowed by th e instead of the VF750F's ca m chain; lef t front cyli nder (t wo ), th e righ t the gea r-drive system was first deve rea r cy li nder (three) a n d the ri g h t fron t cylinder (fo u r) .T he origi na l loped for Honda 's works race bi kes based o n the'VF750F engi ne , and first VF750F fired its second cylinder 90° saw production on th e VFIOOOR . after the first , wi th th e third cyli nder Fr om there , th e differences befirin g 2700 a fter that a nd th e fourth tween .the original, !nt.e!f C;l?tQr.'!.'l4 . __• <;ylil)q~r another 90° a fte r tha t. The

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