Cycle News - Archive Issues - 1990's

1995 Suzuki GSXR1100 By Paul Carruthers Photos by Tom Riles 28 uzuki, it see ms, has never met a di et it d id n't like. Last yea r the com pany brought the moto rcycl in g p ress to Laguna Seca Racew ay to boast abo ut a GSXR750 tha t had spe nt the off-season at a fat farm . This year they brou gh t us b ack to La guna Seca to tell u s - you guessed it - that the Suz uki GSXR1100 had just been released fro m the sa me calorie-in take-reduction cen ter. So jus t how much weight did the big fell a lose? H ow abo u t a whoppin g 22 pounds. Oka y, so it's a tad less rotund what else is new ? Power. Specifically, a IO percent power increase right wh ere you need it - in the midrang e, between 5000 and 10,000 rpm. Other th an that, the GSXRIIOO is basically the same motorcycle as last year - wi th peak power remaining the same - but let' s not forget that it is arguably the mo st su ccessfu l bi g-bore motorcycle in road racing history. First let 's tackle the reasons behind thos e power improvements. New valvetiming s p e ci fica tions and a retuned exhaust sys tem are the reasons give n for the increase in pow er. Less valve overlap seems to be the key to the new timin g specs with th e in ta ke valves now opening at 28 d egrees rath er than 29 and closing at 61 d egr ees rath er than 66. The exhaust valves open at 56 degrees rath er th an 62 w hi le clos ing a t 32 d egre es ins tea d of 36; ex ha us t-valve lift h a s cha nged fro m 8 .6 m m o n la s t year's GSXR to 8.2m m for '95 whil e the lift on the inta ke val ves is unch anged. Val ve size is the sa me and neither the ang le or step d iam eter have bee n altered for '95. The exhaus t sys tem w as changed in ord er to reduce weight whil e al s o enh ancing the new val ve-timing specifications. Th e right side collector section ha s been lengthened a nd the sys te m now uses bolt-on a luminum mufflers similar to the ones used on the RF900R. The s y s te m weighs in four pounds lighter than last year's GSXRIIOO exhaust, tha nks in part to thinner-wall h ead pipes as we ll as the alum inum mufflers. A Suzuki spokesman said that ,the back pressure created by the 1100 doesn't allow for the use of a four -int oon e sys tem, so the four-into-two system remains from years p ast. Following the pattern set by the GSXR750 in last year's weight loss, sev- (Above) The 1995 Suzuki GSXR 1100 - at speed at Laguna Seca. (Left) The new GSXR 1100 featur es a redes igned exhaust system and a new bridged swinga rm, similar to that found on the GSXR750. (Right) Lighter and faster . (Below) The front brake discs are now drilled to aid in the ove rall weight reduction. eral e ngine co m ponents on the GSXR1IOO have been mod ified or have un dergone material change in an effort to reduce weight. The breather cover, valve cover an d signal-gen erator cover have been changed from alumi n um to magnesium; a mounting boss ha s been removed ,fr o m the engine s p roc ke t cover; th e cooling sy stem pipes have been changed from steel to aluminum; the shape of th e cams haf t-ho lder caps have been cha nged to GSXR750 specs; ad d it io na l m ach in in g h a s b een p erfor med on the sig n al-gene ra tor ro to r; .and the lower engi ne-mo un ting spacers have gone from steel to alum inum. Ch a s si s w ei ght ha s al s o b een red uced, mainly by changing the steering-head support tub es to a thinner-wall box-section design. Suzuki claims that the torsional strength of the frame has ' been increased some 26 percent due to thick er-walled 'd o w n tu b es a nd n e w ' cyli n d er -head brackets. The footpegs have been lowered by IOmm, giving the GSXR1100 a much more comfortable rid ing position. The GSXR1100 a lso gets a new sw ing arm for 1995, constructed along the s ame lines as the GSXR750 's. The sW i n g~rm is now a "bridged" design like its sibling 750, but the l IOO unit is 's 55m m lon ger. The right-sid e arm h as been chan ged from pressed aluminum to extruded tubing, increasin g torsional streng th by 5 per cent whil e not gaini ng an ounce of extra weight. The swingarm pivot ha s be en increa sed fr om 20 to .25mm, in order to limit flex. Push-type chain adjuster s with slid in g blocks are also fitted to the GSXRIIOO, again in an effort to save weight. While th e outsid e diame ter of th e forks has ju m p ed to 43mm (u p from 41mm), the primary changes were made to reduce weight. Thus the thickness of the trip le cla mps and ou ter fork tubes have been reduced by 0.55mm. Front axle rigidity has been increased with the addition of a second axle clamp on the left-side fork. Although the 750 features a Showa

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