Question about 2005 Yamaha WR 450 F

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Yfz 450 cuts out

I have a '05Yfz 450 that's giving me trouble.

My timing chain was old and stretched, So i bought a new one and installed it. The timing is right. (TDC and the dots on the cam's is on the right position, I've done it according the workshop manual).

Anyway's when all that was done i've started the quad. The quad is not idling but when i push the throttle in it starts and after a few seconds it just cuts out, And im not leaving the throttle. I hold oit in one place and it starts an cut out in the same throttle position.

What can it be? Mechanical or electrical?

Any suggestions please.

Thank you

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  • justinmor251 Jul 05, 2010

    Thank you. Will have a look tonight. Will keep you updated.


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Sounds like fuel starvation,check fuel tap filter, if the valve tining or ignition timing was out it just wront run

Posted on Jul 05, 2010

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