Currently looking at a C10 and becoming an owner very shortly.  I love the bike and I believe its a good deal, however the person selling the bike is the bike owners son.  He stated that a year ago, the bike had the dreaded hydrolock, and as such a shop replaced the vacuum petcock with a murph's manual petcock.  He said the bike was ridden over the summer (but not sure how many miles). 

I am worried that the bike may have a bent rod due to the hydrolock.  The owner states the bike runs great, and even said he would be willing to drive the 1.5 hours to the airport to meet me (as I am ten hours away).  Is it possible one of the rods could be slightly bent so that the bike would still run fine but this would present a problem further down the road?  How common is it to bend a rod from a hydrolock condition?  This is the only thing holding up the deal, and seeing as how I would be riding the bike 10 hours back to home, I don't want to have a massive engine failure on the way home, and of course I dont want to buy a lemon. 

Any input would be greatly appreciated!!  I would love to be a concours owner and have been looking for one for quite some time.

Welcome aboard, you're in exactly the right place for Concours Camaraderie, and for answers to that specific question among many others.
I'm not the person to answer the question, but while you're waiting for those that do to converge on you like a pack of slathering hounds (friendly hounds, that is...), check out this video from a remarkable guy with all the answers. He is one of the top team here who know everything there is to know...
http://www.zggtr.org/index.php?topic=276.msg142971#msg142971

This subject is so important that the video is accessible from one of the "stickies" at the top of the list of posts. You probably just missed it.

Also, while you're waiting for advice, you might simply search the forum for that word; there's plenty to be had.

I did watch that a bit later after I posted and it just made me a bit more concerned.  I'm very mechanically inclined and really don't want the bike unless I can check that (I'm not sure the shop that installed the petcock would have).  From what I read a slightly bent rod can still allow the motor to run well enough until it blows up, and considering I'd be making a 10 hour trip home on it I certainly dont need the motor to blow and lock up the wheel through New York.  Does anyone know how long it takes to get the bike disassembled to that point?  Since I would be packing my riding gear in a backpack or two, I think I may be able to pack all the tools required to do this check.  If I have to do it in a parking lot near the airport, then so be it, after reading all the horror stories I don't want to get caught with having the split the cases.  If its 2 hours for tear down and reassembly tops, then I think I may be able to convince the seller to let me do this check.

I've had other bikes with the same setup (vacuum petcock thats gravity fed with carbs above the cylinders) and it seems that its more of a problem on this bike.  My 3rd gen magna is the same way and I've never really heard anyone mention the same problem.

You need to pop the seat, take the tank off, remove the coils and pull the plugs - less than 10 minutes if you're mechanically inclined. I've done it, and I'm a relative newb to C10 maintenance. Don't skip removal of the coils! Yes, you'll easily do the whole thing done well inside 2 hours.

Yes, it is more of a problem on this bike because of the lack of carb overflows. Steve Sefsick - the guy in the video, who IS "Shoodaben Engineering" and makes upgrade components that make the C10 "what the Concours shoodaben " - has a mod (carb overflows) that he will do on your carb set to prevent hydrolock, assuming your test is successful. Don't argue or vacillate, just pop them off when you get the beauty home, send the carb assembly to him and he'll make the nightmare go away for a fair price and a couple of days turnaround. Like many people humble enough to take a hint, I did it; hydrolock is now one thing I don't need to worry about. Steve ("SteveInSunnyFlorida" or "SISF" on this forum) is a proven expert at C10 carbs, so he'll give them a worthwhile once-over too.

The C10 is well known to be a little lumpy below 2,000 RPM - although it is nothing less than exhilarating above 3,000; that's just how it is - four CV carbs wandering about aimlessly at idle-level airflow will do that to an engine. Steve's carb mods, a valve clearance adjustment followed by a carb balance will minimize that lumpiness and make a viable C10 bring you to tears of joy. I've had my '06 for 2 years, I've put 30,000 miles on it in that time, and I've loved spinning up every one of them.

Talking of experts, there are several other experts on this forum; you'll figure out who they are soon enough :-) Trust them, and they will look after you and keep you company as your love affair with your Connie develops. Just, for heaven's sake, don't ask about oil - you'll start civil war #213   

Make sure the owner has the OEM spark plug socket tool in the Oem kit or you'll need a thin wall socket (don't know size off the top of my head) in order to remove plugs.

FWIW, I had my C10 hydrolock twice and it did not suffer any permanent damage that I knew of. Of course, when I went to start it and it locked, I knew what it was and right away stopped trying to start it until I fixed the problem. C10s are pretty sturdy motors.

For the plugs if you don't have the OEM socket, it's either a 17mm or 18mm deep well to get them out, but either way, do yourself a favor and bring a 6 inch length or so piece of vacuum tubing that will fit snugly over the porcelain portion of the plug.  This will be of great help in removing and reinstalling the plugs as the wells the are in are quite deep.

For the plugs if you don't have the OEM socket, it's either a 17mm or 18mm deep well to get them out, but either way, do yourself a favor and bring a 6 inch length or so piece of vacuum tubing that will fit snugly over the porcelain portion of the plug.  This will be of great help in removing and reinstalling the plugs as the wells the are in are quite deep.

FIFY

Thanks Joe!    I couldn't recall which it was and had no old plugs lying around (nor any burning desire to check one on the bike)! 

FWIW, I had my C10 hydrolock twice and it did not suffer any permanent damage that I knew of. Of course, when I went to start it and it locked, I knew what it was and right away stopped trying to start it until I fixed the problem. C10s are pretty sturdy motors.

   Have you checked for bent rods?

cleaned the gas out, changed the oil and filter, then ran it for several trouble-free years, so although I didn't disassemble it to check, I don't think the rods were bent.