Bent valves - Yamaha YFZ450 Forum : YFZ450, YFZ450R, YFZ450X Forums
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post #1 of 3 (permalink) Old 04-25-2019, 07:23 PM Thread Starter
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Bent valves

Picked up a non running 2008 yfz450 project. Took the valve cover off to see timing was off 5 teeth on the intake side and 1 tooth on exhaust side. I’m not sure how this happen if the guy messed with it and installed it wrong or how did this happen. Took the head off today the intake valves are bent pretty nicely.

Wondering if the valves guides need to be replaced or be fine with new valve setup? Also piston looks okay other then the marks the valves left should I get new piston? And what about timing chain?
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post #2 of 3 (permalink) Old 04-25-2019, 08:05 PM
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You got it open might as well change as much as you can and start fresh,trying to save alittle now can cost a lot more in the end

Ď16 Yfz450r
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post #3 of 3 (permalink) Old 04-25-2019, 08:50 PM
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If the valves are bent good chance they cracked the guides. Very few times have I seen them survive.

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