Cycle News is a weekly magazine that covers all aspects of motorcycling including Supercross, Motocross and MotoGP as well as new motorcycles
Issue link: https://magazine.cyclenews.com/i/127961
1999 Yamaha YZF·R6 By Mark Hoyer Photos by Paul Carruthers 6 f you have any doubt as to wha t Yamaha's intent was in designing the all-new YZF-R6, consider this: The made-far- racing TZ250 has a rake and tra il of 22°/79.6mm and a wheelba s e of 53 inches; the R6, 24°181mm and 54.4 inches. Not convincing enough? How abou t a 15,50o-rpm rev limit? Or 75 degrees of valve overlap, and 292 degrees of duration on th e. intake and 280 degree s on the exhaust cam, stock - aggressive timing that Yamaha says helps the R6 pr oduce 120 hp at the crank , so me 200 hp / li ter. Perhaps a dry w ei ght of 372 pound s will help erase any doubt you have ab out what this make wa s mad e for . It sho uld, for while this mo torcycle will come from a dealer and be sold for s tre et u se, the numbers th at d escribe this bike say one thing: Let' s race. The templat e for th e R6 w as simple eno ug h to choose, and Yamah a needed to look no further than its very own Rl and a certai n Mr . Miwa - project d irect or for the Rl an d now the R6. The R1 broke th e Open-class sportbike m old , an d if the R6's spec sheet is any indication, so " ill it. As a more compact ve rsion of the R1 - ou r big-bo re shootout winner last yea r - th e R6, from almost every a ngle, is ve ry remi nisce n t of it s bi g broth er, th ou gh it is an e n tire ly cl e an-sh e et d esign and shares, for ins tance, no fairing pan els with the R1 . So w h ile th e lig hts look, well, like Yam ah a " R," you ' ll n o t ice a voi d between them that isn't found on the R1 - t h a t's a n a ir intake that lead s to a seal ed airbox. In other words, ram air - a first on a Yamaha stree t bike. The frame, too, resemb les the R1' s, and does so because it was made in the sa me Deltabo x II vein, but smaller to accommodate the m ore compact 599cc fo u r . It is a lso le s s rigi d , b u t o n ly because it ca n be - th e 105-110 po ni es yo u'll p rob abl y see at the rea r w heel o~ th e R6 wo n 't d em and so m u ch of a chassis as th e 135 hp of the R1. But the con cept is the re, an d of particu lar no te, as on the R1, th e swingarm is longer tha n w hat you'll fin d on o ther b ikes, and can be because the R6 also shares a similar, s hort engine 1 transmi s s ion design (w ith bigger gears than the old YZF) tha t sees th e m a in shafts o f the gearbox stack in a triangular formation. Which also means that, like o n the R1, th e shift linkage takes its straight sho t uphill through the lower-left frame spar, th ough the input sh aft w as made long er , which m ay make it ea sier to cha nge to race-pattern shifting th an on the R1. And w hile the fully adjusta ble rear Soqui shock (Soqui is a company ow ned by Yamaha) - of the "Bilstein type ," says Yamaha - hold s the bik e up on its new, two-inch-lon ger swi ngarm (just like on the R1), the fork is a different affair. Th e R6 is sus pe nd ed by a 43mm con ventional ca rtridge fork that is 2mm larger in d iameter than th e YZF600's and features the fu ll co mp limen t of ad jus tment. On the Rls inverted fork, much was made o f the fact that add itional travel w as included on the ex te nsion side to aid stability on wha t is a bi ke with one of the most d evasta ti ng m id ran ge hits in regular production. But because the R6 builds its power in such a different wa y - by s pin ning its engine very, very fast and building its head of steam rather more grad ually - the extra trav el wasn' t deemed necessary. One item we are particularly glad to The battle lor 600cc Supersport sup remacy heats up with the introduction 01 Yamaha 's allnew , 120 hp R6.