450 convert to 478?

3 replies to this topic
  • rucka356

Posted June 22, 2006 - 08:35 PM


So after 2 years of riding the wheels off of my 450 it looks like it may need a rebuild. My question is, are there big bore kits that work off of just boring the stock cylinder? And are they as reliable as stock? I'm not really wanting to pay $700+ dollars to convert my 450 to a bigger bore.
Any information would be greatly considered!

  • Ga426owner

Posted June 23, 2006 - 05:51 AM


Paid almost less than half of that

and mine is just as dependable so far ... but with a lot more power and torque :excuseme:

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  • crfmatt

Posted June 24, 2006 - 12:35 PM


You would sure benifit from the big bore..but I'm not sure about reliability. The way I see it the engine is making more power and therefore putting more stress on everything, but I may be wrong. Maybe pm grayracer he usually knows everything about these 426's and 450's. :excuseme:

  • yzf450jack

Posted June 24, 2006 - 07:45 PM


Im having good luck with my 470 so far :excuseme: I have all most 2 years on it! I think I did the big bore at the same time I 5 speeded it :bonk: :busted:

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