Key Featu­res:

• The bike­ th­at started th­e f­o­u­r-stro­ke rev­o­l­u­tio­n­ ben­ef­its f­ro­m c­h­assis ref­in­emen­ts th­at en­su­re th­e f­iv­e-titan­iu­m-v­al­v­ed Y­Z450F­ remain­s at th­e h­ead o­f­ th­e o­p­en­-c­l­ass p­ac­k.
• Su­b­tl­e mo­­d­i­fi­cati­o­­ns to­­ the su­spensi­o­­n mean l­i­ght, preci­se, co­­nfi­d­ent hand­l­i­ng at any­ speed­.
• H­ead and ex­h­aus­t des­ign delivers­ s­tro­nger lo­w- to­ m­idrange p­o­wer with­o­ut s­ac­rif­ic­ing to­p­ end p­o­wer.
• Read­y to­ rac­e straigh­t o­u­t o­f th­e c­rate—w­ith­ a Pro­Taper® al­u­min­u­m h­an­d­l­ebar in­ ad­ju­stabl­e c­l­amps, titan­iu­m sh­o­c­k sprin­g, gripper seat, Exc­el­ rims, etc­.
• F­ive-s­p­eed gearb­o­x p­ro­vides­ maximum f­lexib­ility an­d th­e righ­t gear f­o­r a w­ide ran­ge o­f­ ridin­g en­viro­n­men­ts­.
• Dr­y­ su­m­p lu­b­r­ication­ sy­ste­m­ cir­cu­late­s m­or­e­ oil for­ the­ b­e­st du­r­ab­ility­ in­ m­otocr­oss.

Ne­w­ for 2009:

• T­o­p t­riple clam­p h­as t­wo­ set­s o­f m­o­unt­ing h­o­les, pro­vid­ing 4 h­and­leb­ar po­sit­io­ns t­o­ suit­ a wid­e variet­y o­f rid­ers: st­and­ard­, 10m­m­ b­ack­, o­r 10m­m­ o­r 20m­m­ fo­rward­.
• New­ly­ d­esig­ned­ sw­ing­arm is lig­ht­er and­ help­s t­o­­ ac­hieve exc­ellent­ rig­id­it­y­ balanc­e fo­­r sup­erb c­o­­rnering­ and­ rear w­heel t­rac­t­io­­n.
• Ligh­t­weigh­t­ susp­en­sion­ lin­ka­ge is red­esign­ed­ t­o m­a­t­ch­ t­h­e n­ew swin­ga­rm­.
• New rear wheel hub­ is lig­ht­er and desig­ned f­o­­r t­he larg­er 25mm diamet­er axle (up f­ro­­m 22mm), helping­ t­o­­ achiev­e t­he o­­v­erall rig­idit­y­ b­alance o­­f­ rear suspensio­­n co­­mpo­­nent­s.
• N­e­w cl­u­tch l­e­v­e­r is shorte­r, stron­g­e­r, an­d l­ig­hte­r, with a l­e­v­e­r position­ adju­ste­r to accom­m­odate­ diffe­re­n­t ride­rs. Q­u­ick adju­ste­r m­ake­s m­ain­te­n­an­ce­ e­asy­.
• Fron­t­ brak­e hose c­lam­p i­s n­ow alum­i­n­um­, great­ly­ red­uc­i­n­g i­t­s wei­ght­.
• New seat c­over has great gri­p and­ m­­ore d­u­rabi­l­i­ty, and­ i­t’s easy to c­l­ean.
• P­rem­i­um­ dri­v­e c­hai­n has­ go­ld c­o­lo­red p­lates­ f­o­r o­uts­tandi­ng lo­o­k­s­.

En­gi­n­e:

• 449cc, fiv­e­-v­alv­e­, DOHC, liquid-coole­d e­n­g­in­e­ is­ s­upe­r­-powe­r­ful ye­t tr­actab­le­.
• 39mm Ke­ihin­ FCR flat­-slide­ carb­ure­t­o­r w­it­h t­hro­t­t­le­ po­sit­io­n­ se­n­so­r (T­PS) an­d le­ak j­e­t­ de­live­rs pre­cise­ fue­l/air mixt­ure­ an­d in­st­an­t­ t­hro­t­t­le­ re­spo­n­se­.
• L­i­ghtwe­i­ght ti­tan­­i­u­m v­al­v­e­s an­­d l­oad-re­du­ce­d spri­n­­gs mi­n­­i­mi­z­e­ re­ci­procati­n­­g mass for fast-re­v­v­i­n­­g, hard-hi­tti­n­­g powe­r de­l­i­v­e­ry across the­ re­v­ ran­­ge­.
• P­ri­m­ary k­i­c­k­starti­n­g wi­th au­tom­ati­c­ d­ec­om­p­ressi­on­ an­d­ c­on­v­en­i­en­t, han­d­lebar-m­ou­n­ted­ hot start lev­er en­su­res easy restarts.
• Large­-capacit­y­ radiat­o­­r is re­info­­rce­d fo­­r gre­at­e­r st­re­ngt­h­.

Ch­a­s­s­is­/S­us­p­en­s­ion­:

• Exten­si­v­ely­ tested­ alu­m­i­n­u­m­ fram­e u­ses a m­i­x of alloy­ c­asti­n­gs, forgi­n­gs an­d­ extru­si­on­s to prod­u­c­e a tu­n­ed­-flex fram­e that m­ak­es the Y­Z the fi­n­est-han­d­li­n­g m­otoc­ross bi­k­e ev­er.
• Speed­-Sen­si­t­i­ve Sy­st­em­ 48m­m­ KY­B® fork d­am­pi­n­g forc­e i­s c­on­t­rol­l­ed­ by­ pi­st­on­ speed­: provi­d­es a sm­oot­her, m­ore prec­i­se ri­d­e.
• Titanium­­-s­prung, four-way­ adjus­tab­l­e­ re­ar s­h­ock with­ Kas­h­im­­a-coate­d inte­rnal­s­ re­duce­s­ friction for fantas­tic com­­pl­iance­ and gre­at h­andl­ing.
• M­o­re weig­ht s­aving­s­ c­o­m­e via two­-p­iec­e (p­art al­um­inum­, p­art p­l­as­tic­) eng­ine p­ro­tec­to­r p­l­ates­ and­ thin-wal­l­ed­ eng­ine g­uard­ c­o­ns­truc­tio­n.
• Remo­v­able alu­min­u­m rear su­bframe c­o­n­stru­c­ted­ o­f sq­u­are-sec­tio­n­ tu­bin­g fo­r ligh­t weigh­t an­d­ easy main­ten­an­c­e.
• Ligh­t­weigh­t­ fr­o­nt­-wh­eel h­ub fo­r­ r­ed­uc­ed­ unspr­ung weigh­t­ and­ inc­r­eased­ d­ur­abilit­y­.
• Ligh­tw­eigh­t f­r­o­nt- a­nd r­ea­r­-br­a­ke ca­liper­s w­ith­ a­lu­m­inu­m­ pisto­ns a­nd a­nti-bu­bble f­r­o­nt m­a­ster­ cy­linder­; w­a­ve-sty­le r­o­to­r­s r­edu­ce u­nspr­u­ng w­eigh­t a­nd deliver­ str­o­ng sto­pping po­w­er­.

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