0 1 , ▁Yam aha ▁replaced ▁the ▁previous ▁steel ▁val ves ▁with ▁tit an ium ▁ones . ▁The ▁new ▁val ves ▁were ▁more ▁than ▁forty ▁percent ▁l ighter ▁than ▁the ▁previous ▁val ves , ▁allowing ▁for ▁l ighter ▁and ▁so fter ▁val ve ▁spr ings , ▁in ▁turn ▁allowing ▁a ▁quick er ▁rev ving ▁engine , ▁improved ▁thro tt le ▁response , ▁higher ▁rev ▁ce il ings , ▁and ▁more ▁power . ▁The ▁c rank sh aft ▁was ▁also ▁res h aped ▁and ▁the ▁whole ▁assembly ▁was ▁red es igned ▁for ▁quick er ▁thro tt le ▁response ▁and , ▁Yam aha ▁claimed , ▁" less ▁high - end ▁horse power ▁loss ." ▁In ▁addition ▁to ▁motor ▁modifications , ▁a ▁few ▁changes ▁were ▁made ▁to ▁the ▁transmission ▁to ▁help ▁contain ▁the ▁power ▁and ▁ensure ▁lon ge vity . ▁The ▁susp ension ▁also ▁received ▁a ▁bit ▁of ▁an ▁over ha ul ▁with ▁the ▁goal ▁being ▁reduced ▁weight ▁and ▁sm o other ▁action ▁throughout ▁the ▁stroke . ▁Yam aha ▁also ▁designed ▁a ▁new ▁exhaust ▁pipe ▁design ▁so ▁that ▁exhaust ▁header ▁removal ▁would ▁no ▁longer ▁be ▁required ▁when ▁replacing ▁the ▁oil ▁filter . ▁ ▁Car b ure tor ▁tun ing ▁was ▁modified ▁to ▁deal ▁with ▁starting ▁and ▁off - id le ▁take ▁off ▁difficulties . ▁ ▁Also ▁in ▁ 2 0 0 1 ▁the ▁sub frame ▁was ▁changed ▁from ▁a ▁steel ▁to ▁a ▁blue ▁painted ▁al umin um ▁style . ▁ ▁In ▁ 2 0 0 2 ▁the ▁blue ▁painting ▁was ▁stopped ▁and ▁left ▁to ▁a ▁bare