Building a Big Bore Yamaha YFZ450 In 8 Minutes

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[@christophermccartney5833]

Watching this video has shown me just how badly I need to service/tune my WR450F bike... (same engine). Towards the end when you blip the throttle like that, my Yamaha usually drowns and stalls (Carb needs serviced). I'm planning to go for the oversized piston on my bike soon, this video has been very useful to me. Nice work!

[@ononewheel7]

Love the cylinder works/vertex piston kits i run them in all my yfz450r’s! Id look into a spal fan and even adding an oversized radiator for the added heat w the big bore kit!

[@arturomedina5746]

Are these kits good? I'm having a hard time looking for information on a big bore kits(more recent feedback). a buddy of mine wants me to build one for him... but I am also thinking of putting in the port polished head with the +1 kibbles.. and cams. What would be a good intake for dunes on a build like this? His is a 06 yfz.

[@ononewheel7]

@@arturomedina5746 i run an fci intake w a box

[@Davido50]

Yamaha rules sport quads!

[@jodybruce5097]

how do you like the big bore kit? did it add alot more power?

[@versace6230]

Did you have to tune it since you went big bore?

[@kehandroolivier1613]

Did you remove the flywheel when you replaced the timing chain👀?

[@betquick]

What nerf bars are they ?

[@fayabon5976]

Video is soo much more fun watching at 2.0 speed. Music get better aswell

[@joseaponte3423]

Why my 478 is stage 3 why breaking my valve clips

[@gotime1236]

How would you do against mildly built banshee 350's you think??

[@2strokesmoke857]

I had a heavy built stock cylinder and it was shit in the trails I sold they wore not what I thought it was like they are fast ash faster then 450 but it hard to except

[@saritadevidevi3206]

Please

[@saritadevidevi3206]

@@2strokesmoke857 c c

[@pxnteracuatro2313]

How many gears does it have ? Since it’s big bored

[@ryanclarke5128]

A big bore doesn’t change the amount of gears it has🤦

[@pxnteracuatro2313]

@@ryanclarke5128 I have a yfz450 with an athena big bore kit but it doesn’t wanna get 5th for some reason when I go into fifth and give it gas it don’t move it’s like if I was in neutral

[@pxnteracuatro2313]

@Kent Little thanks for the help brotha

[@QdMaster]

@@pxnteracuatro2313 I am guessing you did the stroker kit to obtain true 500 which means something isn't right in the gear box when you re assembled it.... Have to get all new gaskets and take it back apart, always good to check all the gears before fully re assembling the engine, note you can do that by turning the engine with a drill and shifting through the gears ;)

[@deonwashington3756]

More like 8 hours