1993 GS500, Full Yoshi, Lunchbox, 137.5 Jets, still rich?!

[Homer]

the head Homer gave me (which looks beautiful to me, but I'm no expert) is in good condition, and all I end up doing is popping the head off and swapping the other on without spending much money.

That's why I gave it to you.  
It also has a mild PandP, and doesn't have the camshaft side-play.  
The same bolts you remove for the head are the same ones to change the rings.  But, I'm not an engine guy, so I left it alone.  

I've read about some people here reusing the gaskets after cleaning them and re-spraying with copper stuff.  They say the o-rings can be reused also.  
What I've read - the hardest part is keeping the sand out of the case.  A few of the bolts are open to the environment, apparently, and they get packed with sand.  I thought a shop-vac with a reduction nozzle would help, but I've never attempted it.  

Plus, if it's rings - you can sell either of those heads to offset cost.  
Or the clutch pack I gave you.  Or the stator.  Or the side cases.  Or the starter.  Etc.  

Edit:
Plus, it's a pretty good time to put in hotter cams, if you want.  Or have the head decked.  The racers know way more about that stuff than me, though. 

[SlimKlim]

Yeah, those parts are going to be a big help, I'm anxious about tonight, I want to get home and run. Some tests, so I can get some info and devise a game plan.

Cross your fingers for best case scenario.   

[Homer]

My fingers are crossed.
But, out of disaster comes opportunity.  

If you just exchange the entire mill, you could also keep that one on the side.  
Everything else has been done to the bike.
Instead of buying new sprockets, tires, etc, etc... you can make a hot little race engine.  
The parts are around here.  Just set it on the workbench and collect everything.  
When you complete it - sell the replacement for what you paid for it.  
See what I mean?  

I wish Buddha had come through with that replacement.  You'd be all set.  
That's why I dropped the price.  
I had 4 Craigslist offers on it for $1700 that I declined to tell you about.  I really want to hear stories of my old bike beating people at the track, I told you.  I want to see pictures of it leaned into corners, because I'll never be able to do that.  
That's why I wanted it to go to you.  

Edit:
Look at those HP and torque numbers from the Veypor dyno again.
Those are close to numbers for a perfect, stock engine.  See what I mean? 
Outside of the engine, there's nearly every modification for power gains - outside of lighter wheels, titanium axles, lightened brake rotors, and ceramic bearings (which I was actually about to do - all of it).   

With a guarantee-able stock motor - you could beat the pants off 95% the people here.
With cams - 98%
With a displacement kit - 99.8%

Only 2 GS500s in existence would beat you in the straights.
Ice's turbo:
http://gstwins.com/gsboard/index.php?topic=34218.0
Werase has the parts for it, by the way.

And, the one with the GSXR 1/2 head swap.  Dgyver ALMOST made one, but never finished it. 

[badguy]

If you end up wanting to sell that head, please let me know.  Good luck with the bike.