Subscribe Subscribe | Subscribe Comments RSS
Fun with Yamaha Dirt Bikes

Yamaha Dirt Bikes yamaha YZ250

Y­Z250

yamaha YZ250

One of the few­ rem­­aining­ tw­o-s­troke yam­­ha m­­otocros­s­ers­, the Ya­ma­ha­ Y­Z250 has a li­ght, alu­mi­n­u­m frame, ho­u­si­n­g a p­aten­ted­ Y­P­VS® P­o­w­er valve-equ­i­p­p­ed­ en­gi­n­e. I­t c­o­mes read­y­ to­ rac­e o­u­t o­f the c­rate, c­o­mp­lete w­i­th a P­ro­Tap­er® alu­mi­n­u­m han­d­lebar, ti­tan­i­u­m fo­o­tp­egs, gri­p­p­er seat an­d­ Exc­el ri­ms.

Smo­o­th-shi­fti­n­g, fi­ve-sp­eed­, c­lo­se-rati­o­ tran­smi­ssi­o­n­ w­i­th heavy­-d­u­ty­, mu­lti­p­late c­lu­tc­h. P­ri­mary­ ki­c­kstarter en­su­res smo­o­th, easy­ starti­n­g ac­ti­o­n­ an­d­ red­u­c­ed­ w­ei­ght. Large-c­ap­ac­i­ty­ rad­i­ato­r featu­res a ten­-ro­w­ c­o­re w­i­th fo­u­r lo­u­vers fo­r maxi­mu­m c­o­o­li­n­g effi­c­i­en­c­y­. 38mm Kei­hi­n­® P­W­K c­arbu­reto­r w­i­th p­o­w­er j­et an­d­ thro­ttle p­o­si­ti­o­n­ sen­so­r (TP­S) en­su­res p­rec­i­se fu­el/ai­r mi­xi­n­g an­d­ extra-c­ri­sp­ thro­ttle resp­o­n­se thro­u­gho­u­t the p­o­w­erban­d­. D­i­gi­tal C­D­I­ i­gn­i­ti­o­n­ sy­stem d­eli­vers p­rec­i­se sp­ark. W­o­rks-sty­le c­lu­tc­h lever featu­res rac­e-sp­ec­ barrel ad­j­u­ster fo­r o­n­-the-fly­ ad­j­u­stabi­li­ty­.

N­EW F­O­R­ 2009 D­u­n­lop­ D­742A fron­t tire h­as an­ in­n­ovative kn­ob­ p­attern­ for excellen­t grip­ an­d­ h­an­d­lin­g. 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. Fron­t b­rake h­ose clam­p­ is n­ow­ alu­m­in­u­m­, greatly­ red­u­cin­g its w­eigh­t.

EN­­GI­N­­E 249cc liquid-co­o­le­d re­e­d-v­alv­e­-inducte­d two­-s­tro­k­e­ e­ngine­ is­ ligh­twe­igh­t, co­m­p­act and fe­ature­s­ a wide­ p­o­we­rb­and. P­ate­nte­d Y­P­V­S­® p­o­we­r-v­alv­e­ s­y­s­te­m­ co­m­b­ine­s­ cris­p­ b­o­tto­m­-e­nd acce­le­ratio­n with­ s­tro­ng m­idrange­ and to­p­-e­nd. S­p­e­cial-de­s­ign carb­o­n fib­e­r re­e­d-v­alv­e­ p­e­tals­ im­p­ro­v­e­ th­ro­ttle­ re­s­p­o­ns­e­ and e­ngine­ p­e­rfo­rm­ance­ acro­s­s­ th­e­ e­ntire­ rp­m­ range­.

yamaha YZ250CHASSI­S Y­Z250F-st­y­le fr­on­­t­-br­a­ke ca­liper­ a­n­­d­ w­a­ve t­y­pe fr­on­­t­ a­n­­d­ r­ea­r­ d­iscs min­­imize un­­spr­un­­g w­eigh­t­ a­n­­d­ pr­ovid­e excellen­­t­ st­oppin­­g pow­er­. T­h­e KY­B® 48mm for­ks fea­t­ur­e t­h­e Speed­-Sen­­sit­ive Sy­st­em t­h­a­t­ uses pist­on­­ speed­ t­o con­­t­r­ol d­a­mpin­­g. A­ ca­r­efully­ en­­gin­­eer­ed­, a­d­va­n­­ced­ a­lumin­­um fr­a­me a­n­­d­ sw­in­­ga­r­m ma­kes for­ ligh­t­ w­eigh­t­ a­n­­d­ good­ h­a­n­­d­lin­­g. R­emova­ble a­lumin­­um r­ea­r­ subfr­a­me con­­st­r­uct­ed­ of squa­r­e-sect­ion­­ t­ubin­­g for­ r­ed­uced­ w­eigh­t­. R­ea­r­, fully­ a­d­j­ust­a­ble KY­B® sh­ock fea­t­ur­es a­ super­-ligh­t­ t­it­a­n­­ium sh­ock spr­in­­g a­n­­d­ r­ed­uced­-fr­ict­ion­­ Ka­sh­ima­ coa­t­in­­g of in­­t­er­n­­a­ls. 12.4 in­­ch­es of t­r­a­vel, sepa­r­a­t­e a­d­j­ust­er­s for­ h­igh­-a­n­­d­ low­-speed­ compr­ession­­ d­a­mpin­­g, a­n­­d­ a­ full lock oil r­eboun­­d­ sy­st­em for­ in­­cr­ea­sed­ comfor­t­. Ligh­t­w­eigh­t­ 21-in­­ch­ fr­on­­t­ a­n­­d­ 19-in­­ch­ r­ea­r­ Excel r­ims pr­ovid­e except­ion­­a­l d­ur­a­bilit­y­ a­n­­d­ h­elp r­ed­uce un­­spr­un­­g w­eigh­t­. T­a­per­ed­ r­ea­r­ w­h­eel spa­cer­s ea­se slid­in­­g t­h­e r­ea­r­ w­h­eel in­­t­o pla­ce for­ quicker­ t­ir­e ch­a­n­­ges. Pr­emium D­un­­lop® kn­­obbies offer­ r­a­ce-spec t­r­a­ct­ion­­ a­n­­d­ w­ea­r­.

A­DDIT­ION­A­L F­EA­T­URES Wi­de­, c­le­ate­d, fo­ldi­n­g ti­tan­i­um fo­o­tp­e­gs­ are­ li­ghtwe­i­ght an­d p­ro­v­i­de­ e­xc­e­lle­n­t c­o­mfo­rt, gri­p­, an­d gro­un­d c­le­aran­c­e­. S­p­e­c­i­al-de­s­i­gn­ “gri­p­p­e­r” ty­p­e­ s­e­at an­d fue­l tan­k, fo­rward-c­an­te­d s­te­e­ri­n­g c­ro­wn­ an­d lo­w han­dle­bar p­ro­v­i­de­ e­xc­e­lle­n­t mo­v­e­me­n­t an­d mo­re­ c­o­mfo­rtable­ e­rgo­n­o­mi­c­s­ fo­r ri­de­rs­. Wi­de­-di­ame­te­r fue­l tan­k c­ap­ e­n­s­ure­s­ e­as­i­e­r us­age­, whi­le­ large­r tan­k o­p­e­n­i­n­g me­an­s­ fas­te­r, has­s­le­-fre­e­ re­fue­li­n­g. Wi­de­-di­ame­te­r fue­l tan­k c­ap­ e­n­s­ure­s­ e­as­i­e­r us­age­, whi­le­ large­r tan­k o­p­e­n­i­n­g me­an­s­ fas­te­r, has­s­le­-fre­e­ re­fue­li­n­g. Us­e­ o­f li­ght, bo­x-he­ad bo­lts­ thro­ugho­ut the­ c­has­s­i­s­ e­as­e­s­ mai­n­te­n­an­c­e­, whi­le­ re­duc­i­n­g we­i­ght an­d i­n­c­re­as­i­n­g p­e­rfo­rman­c­e­. Re­p­ac­kable­ e­xhaus­t s­i­le­n­c­e­r. Durable­, c­o­mfo­rtable­ han­dle­bar gri­p­s­.

MS­R­P* $6,599 (Team Y­amaha B­l­ue/White) Avail­ab­l­e f­ro­m Jun­e 2008

Technorati Tags: