07 valves sticking?


31 replies to this topic
  • snoplw

Posted October 26, 2007 - 08:09 PM

#21

I agree on that it depends on the dealer sometimes they can find some how to warranty they need to be tactfull on the claim. One thing to think about is kibblewhite valves are good alternative to stock and are more economical. I used stock oem because I did not want to wait for parts. Also my guides were fine. rember though different valves require different keepers etc. I do feel your pain these thumpers are not cheap to do I had 200.00 into mine and it was just the exhaust valves. Good luck.:worthy:

  • todds924

Posted October 26, 2007 - 08:41 PM

#22

They drove 2 hours to pick your bike up?....Wow, thats good customer service. But, I don't trust dealers, I'd make the trip.


Tell them to save the parts FOR SURE if you cannot get up there to see it.

  • grayracer513

Posted October 26, 2007 - 09:01 PM

#23

One thing to think about is kibblewhite valves are good alternative to stock and are more economical.

The valves are a little less expensive, but they require the matching spring set (because they weigh twice as much), which includes titanium retainers, and goes for over $200. By the time the smoke clears, you won't save much, and they aren't any more reliable than Yamaha OEM.

  • rmracer27

Posted October 27, 2007 - 02:36 PM

#24

Here is some pics of the valves.

Posted Image

Posted Image

Posted Image

Here is the head after they cleaned it.

Posted Image

  • 642MX

Posted October 27, 2007 - 02:40 PM

#25

Interesting. I wonder why the springs broke?...

The exhaust valve seats look corroded. Maybe its a shadow on the picture of something....

  • rmracer27

Posted October 27, 2007 - 03:04 PM

#26

Interesting. I wonder why the springs broke?...

The exhaust valve seats look corroded. Maybe its a shadow on the picture of something....


Thats a shadow or something. They are really clean.

Visit the ThumperTalk Store for the lowest prices on motorcycle / ATV parts and accessories - Guaranteed
  • grayracer513

Posted October 27, 2007 - 03:37 PM

#27

Both springs broken in the same place, near the end of the coil. Springs assembled too short would be my guess, but who knows why?

  • snoplw

Posted October 27, 2007 - 03:43 PM

#28

i guess i will retract my full of it line if those are the springs. both broke same spot??? that my friend should be a real possible warranty if pushed

  • rmracer27

Posted October 27, 2007 - 03:44 PM

#29

They are saying its over rev or its from where the valve's was sticking in the guides.

  • snoplw

Posted October 27, 2007 - 03:47 PM

#30

i was wrong before but i have reved mine to the moon squeezing a little more. the rev i don't agree with maybe just bad springs.

  • grayracer513

Posted October 27, 2007 - 03:57 PM

#31

They are saying its over rev or its from where the valve's was sticking in the guides.

Valves sticking in the guides won't cause that. Only three things will, and all for the same reason.

It looks like the springs were coil bound (bottomed out, so to speak), which they would have done only if the valves floated, which should be impossible with a rev limiter, or the springs did not have enough installed height, and bound when fully compressed.

But there is a third possibility, and that is that you over revved it mechanically by down shifting too far too soon. The rev limiter can't protect against that.

  • rmracer27

Posted October 27, 2007 - 04:00 PM

#32

I don't think its over rev. I don't remember down shifting and cause it to over rev. I have rode my 05 yz450f with over 100 hours and never had a drop of trouble with the valves. Never even had to adjust them. Hopefully it won't do this all over again.





Related Content

Forums
Photo

2016 YZ450 by CaptainKnobby


Dirt Bike   Dirt Bike Technical Forums   Suspension
  • Hot  59 replies
Forums
Photo

Chubby dad, looking at bikes , First trip to the orange/black forum ! by Slow_ride


Dirt Bike   Make / Model Specific   KTM   250-530 EXC/MXC/SXC/XC-W/XCR-W (4-Strokes)
  • Hot  28 replies
Forums
Photo

Michigan Motocross Tires by 288yz450


Dirt Bike   Dirt Bike Regional Discussion   North
  • 1 reply
Reviews

Yamaha YZ450F 2017 by Chris.GVS


Yamaha YZ450F 2017
  • - - - - -
  • 0 reviews
Forums
Photo

Snake pit oct 30th by The Anvil


Dirt Bike   Dirt Bike Regional Discussion   California
  • Hot  293 replies
 
x

Join Our Community!

Even if you don't want to post, registered members get access to tools that make finding & following the good stuff easier.

If you enjoyed reading about "" here in the ThumperTalk archive, you'll LOVE our community. Come join ThumperTalk today!

The views and opinions expressed on this page are strictly those of the author, and have not been reviewed or approved by ThumperTalk.