07 450 head question


8 replies to this topic
  • gtsmpuc

Posted April 15, 2011 - 01:35 PM

#1

Do these valves look like they are seated right, as far as the build up of carbon on either side of the smooth surface of the seat? The bike was put back together out of time, when i got it and you can see small scuffs on the piston and the 3 intake valves. Valves slide great in the head, so im thinking new springs and just put them back together. Also what is a good cleaner for the head and the valves, to remove the carbon build up.


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  • gtsmpuc

Posted April 15, 2011 - 02:27 PM

#2

here are the spots where the valves touched the piston. Motor was completely out of time when i tore it down, piston was also rolled over. Guy said he thought the crank was bad, it checked out great, but not sure what caused this.

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  • grayracer513

Posted April 15, 2011 - 03:03 PM

#3

Yes, they look alright assemble them, tap the stems lightly with a small hammer to bounce the valves off the seats a little, then check them for sealing with solvent. Back in the days when you could get "real" carb cleaner, there was something that would just dissolve the carbon off the valves by soaking them overnight and then lightly brushing. Now, I don't know of any one thing that's better than anything else. You can use a wire brush on a bench grinder, BUT DON'T brush the sealing face of the valve or the part of the stem that runs in the guide.

  • Gunner354

Posted April 15, 2011 - 04:03 PM

#4

WD-40 will remove the carbon. Submerge and let it set overnight.

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  • grayracer513

Posted April 15, 2011 - 05:25 PM

#5

Haven't tried that. Maybe WD-40 is good for something after all. :thumbsup:

  • Handy Andy

Posted April 15, 2011 - 08:00 PM

#6

You can still get the good ol' carb cleaner but only in 5 gal. buckets which is not very cost effective for personal use. You probably can't get it in CA though.

  • grayracer513

Posted April 15, 2011 - 08:20 PM

#7

You can still get the good ol' carb cleaner but only in 5 gal. buckets which is not very cost effective for personal use. You probably can't get it in CA though.

Yeah, but the stuff works so well that I'd buy one and just use it for the next ten years. I used to bring the old stuff home from the dealership that the tune up guys didn't want anymore and use that. Maybe next time I drive to Arizona....

  • gtsmpuc

Posted April 15, 2011 - 08:50 PM

#8

Thanks everyone! Im pumped to get a new top end ordered next week and try to fire it. Before i pulled the valve, i did spray some degreaser in the head, it was all i had. After sitting about 2-3 minutes, you could see dampness coming through the valves. It wasnt wet, but like damp concrete. Thats when i pushed on the valve and when it seated you could hear the carbon or dirt on the seats. In the pic of th valve it was after i wiped it off with a rag.

  • Handy Andy

Posted April 15, 2011 - 09:02 PM

#9

Yeah, but the stuff works so well that I'd buy one and just use it for the next ten years. I used to bring the old stuff home from the dealership that the tune up guys didn't want anymore and use that. Maybe next time I drive to Arizona....


I love that shit.





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