I was at a Pumpkin Patch yesterday with family and noticed the farmer had two Fl350's sitting outside getting very weather beaten. I talked to an employee who said they hadn't run in years. Don't know if he'd sell them, I'm not interested. They were in Granite Bay, California so you'd need to be close to go over there and talk to the owner to see if they'd even entertain an offer.

Did you take any pictures while you were there ?
CO

Nope. I wasn't interested. If they were Pilots I would've tried to buy them!

The way I see it right now the Pilots have a big weak spot.
You can't get that double lip seal anymore for the crank and nobody seems to have found a replacement. Even I have looked and haven't found a replacement and I don't even own a Pilot. I looked just for personal interest and personal info.
You can still get the double lip seal for the FL350 from England.
Engine mounts and intakes for the FL350 I make myself from two part rubber.
CO

I have several of those double lip seals and many other hard to find parts. I have several Pilots so I'm always on the lookout for machines and parts. I used to have 4 FL350s, but once I got my first Pilot, I sold all my Odysseys

On the Pilots I have never had a balancer side crank seal go bad or wear out, when I have them apart I change them. The balancer seal on the balancer case side is bathed in oil its entire life. The other side of the seal faces the crank case and is bathed with gasoline and 2 stroke oil so they last a really long time. I even saved a few of my used balancer side seals for emergency use.

The Honda OEM crank seals on all their 2 strokes were of top quality, I have talked to may 2 stroke owners who ran race fuels and they never had problems with the fuel affecting the rubber.

The clutch side seal on Fl350 and Pilots is the one to worry about the most as its subject to the elements, they wear faster and easier, they are also subject to more heat soak from the Engine cases.

In a pinch I have taken a used and just worn crank seal that was starting to leak, slight bubbles on a pressure test, remove the seal, carefully removed the spring on the inside. Look close at the spring, the ends of the springs thread together, when you find where they join unscrew the spring it will snap straight carefully cut off about 1/8" screw it back together. The shorter spring will apply more tension on the rubber and it should seal (mine did) I ran my used seal for about another 50 gallons of gas through the Engine before changing.

NOTE: Inspect the used seals for dry rot, cracks etc. If the rubber is degraded REPLACE!

I thought ATV Racing just used a single lip/spring seal on the balancer case side after Honda discontinued? I do not see why it would not work, same application as the clutch side, the only difference is it would be running in balancer oil rather than exposed to the elements of Off-Road. In theory should outlast the clutch side crank seal as the outside facing side of the seal being in a cleaner environment bathed in oil.

No doubt Honda used the double lip double spring seal on the balancer case for reliability, and good engineering practices.

ALWAYS PRESSURE TEST the crankcase after changing the seals and verify they are not leaking!

Pro Tip I always put 2 stoke oil on the seal before installing. Just the side of the seal that contacts the crankshaft. I also put a lite coat of oil on the crankshaft, you do not want dry rubber rubbing on dry steel. The outside of the seal I leave dry and ensure the crank cases are clean and free of oil to reduce the chances of the seal blowing out under crankcase compression or a backfire.