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Jonski

01 yz426

10 posts in this topic

So I bought an 01 426. Was very clean, looked taken care of and had lots of power...

Well after about 20 hrs the rod bearing locked up on me.

Should I spend the money and build it or part it out and get a new bike?

Maybe throw an 03 450 head and jug on there?

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Bump...

So just the rod bearing went out... Everything else looks fine. I am going to take the valves off and check the runout.

If the valves still look good, what all would y'all recommend replacing? Local mechanic says replace valves, replate cylinder and new crank... That's gonna rack up real fast!

I'm thinkin bout parting it out. Is there a decent market for parting out the 426?

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Have the cylinder professionally measured.  The wear tolerance is a max of .002" variation at any point within the bore.  It's that small because the Nikasil coating isn't any thicker than that.  If it exceeds the spec, you have 3 choices: Replace it, replate and refinish it, or use it as a core cylinder for a big bore kit. 

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Cool I'll measure it tomorrow... I work at a machine shop.

What all is involved in doing the big bore kit?

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Buying and installing it.  Most come with a piston fit to the bore and the appropriate top end gaskets.

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So I'm considering parting out the 426 and moving up to a newer wr 450...

Opinions...?

Anyone needing 426 parts?

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So I'm considering parting out the 426 and moving up to a newer wr 450...

Opinions...?

Anyone needing 426 parts?

Yeah I need a California license plate for an 01 426! Edited by G-BRO

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