Cycle News - Archive Issues - 1980's

~ Impression: 1988 Suzuki GSXR750 ~ The street-going racer By Pau l Carruthers Photos by Henny Ray Abrams O n e look at the all -new 1988 Suzuki GSXR750 brings visions of the exotic fourstroke machinery used in 'en du rance road races such as the Suzuka 8-Hour. Sitting on th e new GSXR750 feels similar ' to sitting astride a 250cc Grand Prix road racer. Riding ' the Suzuki GSXR750 on a race track brings abo ut th e rea lity th at th i s is a rgua b ly th e bes t highperformance street bike available in the U. S. tod ay. Suzuki 's press guide states that th e co m pan y " starte d with a rea l race bi ke, and disti lled it down to a stree t bike." T he gui de is correct; the new GS XR75 0 looks race tra ck ready a nd virtuall y is. T his one wi ll be more at ho me goi ng between turns one a nd two tha n between home and the grocery stor e, and that 's proba bly why Suzu ki chose to introdu ce it to the mo torcycle p ress corps at Laguna Seca Intern a tiona l Raceway. . 6 Changes! The new GSXR750 is exactly that - n ew. Th e c ha n ges start with appeara n ce; th e GSX R 750 h a s recei ved cosmetic changes wh ic h incl ude a new aerodynamic fai ri ng with redu ced frontal area ; a new tail sectio n and a new rear fender. The bike si ts lower with a 12mm lower cen ter o f gravity, and a sea t height of o n ly 30.9 in ch es. T he GSXR also has a ground clearan ce of only five inch es wh ich , as we will get to later, in it iall y ca used the bike to grou nd through corners a t Lagu na . Wheel base has been shortened from 57. 1 to 55.4 m ch es. The 749<;c double-overhead ca~ , lfi-valve, air-coo led po,;,erpl am I S al so changed rather rad ica lly. The new engm e featu res a shorte r stroke and a larger bor e, fro m 70 x 18.7m m to 73 x 44.7mm , resu lti ng in hi gher cra n k speed (the cra n k itself has been strengthened), larger valves (26 to 28.5mm in takes a nd 24 to 25mm exhaust - the sam e as last year's GSXR lIOO) a n d redu ced p is to n spe ed. The cyli n d er is ba si call y un chan g ed, b ut the pi st ons a re sma ller, sho rter a nd lighter , featurin g hol es for lightening and stai nless steel com p ressio n rings; th e dome design on the new pi stons has a lso been cha nged. The cylinde r head features a n in creased porting angle and the ridge betw een valv es has been rem oved to stop detonation. Rocker arms have been lightened , and different valv e tim in g a nd increa sed val ve lifts have been in corporated . In tak e o n th e new Suzuki has been alte red with a new fresh a ir system being used. T he intak e tak es a ir from the front and carr ies it up under th e frame ra il to the airbox, The airbox it self uses a paper eleme nt fil ter for 1988. All ne w. Th e 19 8 8 GSXR features a new engine in a new alumin umalloy constructed fram e, using a larg e cross-se ctio n, box-a lu min um c onstruction for the s w inga rm . It's a pure ra cer that's s treet leg al. . . T he carbu retors have al so changed for 1988. This year's GSXR750 uses 36m m fla t sli de Mikunis (last year's used 31m m carbs) that feature lighter return sp rings; desig ned to offer a . light an d respo nsiv e' feel (the sli des ' , ar e sim ilar to those used on Suzu ki's RM m o to crosser s ). T h e ve nturi veloci ty has also been in creased and th e .new Mikunis use fewer overa ll parts, in an effort to mak e the m easier to work o n. T he floa t a nd needle valv e come off as a unit ins tead of , separa tely. . The lubrication and oil cooli ng is mostl y the sa me on th e new GSXR. The o il coo ler, however, features n ew 15-row co ns truc tio n which ' offers a 48% in crease in oil capaci ty. Larger oil lines a nd new fittings also mean a mor e direct flow (a 20% flow inc rease) . The increase 'is ne eded because o f th e ' increased heat and power of th e new engine. Oil capac: ity is up one quart from 5. 1 quarts to 6.1. This year's clutch is cable operated ins tea d of hydraulic. T he unit also , a uses beefier clu tch p lates, although the a mo unt o f pl a tes is unch anged a t 17. T he gear ra ti os hav e not changed th rou ghou t th e six -speed tra nsmissio n. T he ig n itio n on th e GS XR is' a dig ital, compu ter -controlled system whi ch is p re-p rogra m med for op timum ignition cUJ'Ve. A new spark plug is used, fea turing two grou nd electrodes wh ich ar e ver y short and . light to wi thstand vibratio n and flutter ing whi le helping maxi mize p lu g li fe. T he n ew Suzuki a lso features a gear-driven AC alte rn a tor, giving more power at higher rpms. The engine isn' t th e only part o f the new GSXR750 that has undergo ne 'extensive cha nges. The frame is a n a ll -new a lumi n u m alloy con str uction, . fea turing a la rge crosssectio n , box-aluminum cons tructio n for th e swingarm. T he steer ing head is a cast unit like previous mod els, a nd th e en tire pack age is m ore co m pact a nd ri gid. Suzu ki claims th e tubing on th e new frame is over 10% stronger.

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