Valves


10 replies to this topic
  • finthat

Posted April 09, 2009 - 04:16 PM

#1

Have my engine apart still and pulled all the valves to clean ect. I noticed the two outer intakes were very carboned up and the center was clean. Would I asume the two outside valves would be out of adjustment?? Haven't found my feeler guages yet.

  • grayracer513

Posted April 09, 2009 - 05:04 PM

#2

No, that's a normal condition. Because fuel is heavier than air, it doesn't "turn out" into the outer ports as well as the air does. Because of that more fuel flows over the center valve, and washes it cleaner than the outer two.

  • finthat

Posted April 09, 2009 - 05:08 PM

#3

Ok that makes sense. I was also told if the buckets have a circle (not sure how to expain) on them it is a sign the valves are out as well, not sure if it makes sense or not.

  • grayracer513

Posted April 09, 2009 - 05:37 PM

#4

That's not true either.

Did you measure the clearance before you took it apart?

Here's a couple of tips on visual inspection:

http://members.cox.n...yzer/valves.htm

  • finthat

Posted April 09, 2009 - 05:52 PM

#5

That's not true either.

Did you measure the clearance before you took it apart?

Here's a couple of tips on visual inspection:

http://members.cox.n...yzer/valves.htm


No I didn't, I bought the bike with a thrown rod and tore it down right away. I just want to make sure everthing is in spec while out of the bike. Checking the valves with the head off will work won't it??

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  • finthat

Posted April 09, 2009 - 05:57 PM

#6

Good pics thanks

  • finthat

Posted April 09, 2009 - 06:12 PM

#7

I am going to be pulling the valves out to change the seals anyhow so I will do a closer inspection of them then.
I also just found my fealer guages and they seem to be in spec. I do need narrower guages to make this job easier though.

  • grayracer513

Posted April 09, 2009 - 07:20 PM

#8

You can check valve clearances on the bench, yes. Torque the caps to about 60-70% of spec and check them with the cam lobe pointing straight up away from the valve (or lined up in the timing position).

It is always advisable to double check following reassembly in case torquing the head has an effect on it.

  • finthat

Posted April 09, 2009 - 07:52 PM

#9

Thanks alot. As I said before I think the valves are going to be in spec and all should be good as long as the wear is ok. I think, by the shape of the rest of the parts, there nothing should be worn out just yet. Every thing that can be abused by low matainance, bearings crank ect., I have already changed out. Thumbs up again.

  • CaptainKnobby

Posted April 10, 2009 - 09:40 AM

#10

That's not true either.

Did you measure the clearance before you took it apart?

Here's a couple of tips on visual inspection:

http://members.cox.n...yzer/valves.htm


So my valves should be alright in my 06 450 with 81 hours on it?

I take care of the oil changes and air filter after every race and practice.
More than I should I guess.

  • rexbond007

Posted April 10, 2009 - 11:06 AM

#11

i Have 125 hours on my 450 and valves are still in spec from factory but saying that, no two bike are identical





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