Cylinder head resurface info

I have searched and searched on TT but nothing comes up and on YouTube videos there are only multi-cylinder head resurfacing videos. I am looking for a how-to video on the proper way to do it without a machine with flat glass or granite with wet-sanding technique in the figure 8 motion. I am leaving on a two week trip to Scottsdale, AZ with a stop in Las Cruces, NM for a couple of days. I will be bringing my WR250F with me but I would like to hustle and get the WR450F completed before this coming Friday morning. I am in Round Rock, TX and not familiar with any shops that are reasonable for this work in my area. The head is apart and valves out ready for surgery. Does anybody have any leads for me or cost estimate or in my area that wouldn't mind coming over to guide me? I have all the materials to do this myself but not knowledgable to know for sure if I'm doing it right. The fridge contains food and beer FYI!

I have searched and searched on TT but nothing comes up and on YouTube videos there are only multi-cylinder head resurfacing videos. I am looking for a how-to video on the proper way to do it without a machine with flat glass or granite with wet-sanding technique in the figure 8 motion. I am leaving on a two week trip to Scottsdale, AZ with a stop in Las Cruces, NM for a couple of days. I will be bringing my WR250F with me but I would like to hustle and get the WR450F completed before this coming Friday morning. I am in Round Rock, TX and not familiar with any shops that are reasonable for this work in my area. The head is apart and valves out ready for surgery. Does anybody have any leads for me or cost estimate or in my area that wouldn't mind coming over to guide me? I have all the materials to do this myself but not knowledgable to know for sure if I'm doing it right. The fridge contains food and beer FYI!


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If your just pulling apart a Yamaha head it shouldn't need resurfacing. The stock head gaskets seal pretty well. 

I initially pulled it apart a few years back because I had oil coming out of the head gasket below the exhaust port. I ordered a new OEM gasket kit and put in a new cam chain, piston and rings since it was apart anyways and torqued everything to spec. I never assumed any head warp at this time, neglected to check, just put on the new gaskets. After a couple easy rides, it started coming out again so I disassembled it again and ordered a Tusk brand gasket kit and I took it to a friends house so he could show me how to resurface it but I did not complete the resurfacing that day. I took the head home with hopes of finishing it up but my Attention Deficit Disorder kicked in and I got to working back on the problem with my WR250F instead. Well, the WR250F problem is fixed and now I'm back to trying to complete the WR450F problem that is more of a pickle to me since I have never resurfaced a cylinder head before. I am mostly intimidated by the amount of clearance afterwards such by being too much or not enough and if I take it down too much, should I add an additional base layer gasket to make up some of the lost material from the material that was removed? I'm mostly concerned about the valves coming closer to the piston. Like I said, I'm a head resurfacing virgin and looking to be given a dirty lesson to. I just want my first time to be special.

Here is an update. I took a red Sharpie and marked the surfaces and then proceeded to do the figure eight motion with 400 grit while drizzling water over the surface and took it down until the marked areas disappeared. The only area of concern was what you see in the following pictures where the red remains. It is the spot near the exhaust port. The cylinder was good with the exception of a super small nick at the edge(see picture).
Is what I have done close enough? Should the new gasket be enough to fix what minuscule amount is slightly remaining? Last picture is of cylinder with nick in it if you look close. Not in the cylinder but on the lip of it.
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It looks good to me.

Excellent job, probably good as is but keep going and clean up that head. 

With 400 grit paper you will have a hard time taking 0.010" off, which would be the start of a problem. The water is not really required (it does keep the paper sharper) and you could have used a coarser grit. I think your nick will be fine, but if there is a sharp edge you can file (small jeweler's file) or stone it out. 

I have done a lot of this work with emery paper, glass and hand tools, mainly with 2 strokes but have done 4 strokes and multi-cylinder engines as well. Have filed blocks and heads down with a large coarse file to reduce squish gap, increase compression and improve seal. On assembly you can check the squish gap with 0.060" lead solder to see if everything is right (about 0.040"). 

Good work! 

Those valve seats don't look very good. Dont' try to lap them, just use green scotchbrite.

If you are changing valves, you will need to have them re-cut regardless. Lapping will not work for this valve type.

you can do this with a block of wood as well.

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