Power loss in rain

Just picked up my bike from winter storage. Started at the first touch of the button!

However, on the 250 mile ride up to my new residence, I had some problems when the rain started falling. Basically, it would start losing power, feeling a lot like it was gas starved. BUT, petcock working and supply of fuel visible in the filter going down.

If I stopped, it would stall out, then start again after a couple of minutes and be fine for a few miles. Eventually, I found it would sometimes cure itself if I kept at the throttle, and was less likely to happen if I went faster. At no time did it sound like it was missing a cylinder or two (though I'm not sure what it would sound like). None of the pipes seemed cold.

Thought to blame blockage in the carbs, but when it was in "crappy mode" adding choke would actually kill the engine. So maybe electrical? A couple of times I tried reaching down to make sure the plug wires were all the way on and got shocked (wet glove) -- is this normal?

Anyway, is this adding up to anything? I searched around here and saw maybe my coils were getting wet, but I would have thought the resulting missing would be more obvious. Instead the engine is just weak and responds to rolling on by doing nothing or getting even weaker. My only other thought was maybe water getting in my air intake. I checked and saw some drops of water in the airbox, but could that really have that much of an effect?

I don't know if I'm right or not, but I always thought this was the spark plug boots getting wet for some reason. Probably because many times I've been sitting in the rain, go out and start the motorcycle only to find it runs like crap, and I know darn well nothing has got wet other than the plugs and wires. Other times I've been riding through rain and the exact same scenario, so that's what I've always thought was the problem. Strange thing is maybe one day the bike's flooded with 2" of rain and runs fine, next drizzel and runs like sheet. This has happened to me on probably 20 KZs at one time or other over the years.

I don't know if you saw my post in the past on dying in the rain.
I had a short front fender on from an LTD, and water would get flung up under my tank and wet the coils and wire connections. My bike slowly started to die, then did all together. Pull my tank and the coils were dripping.
I solved the problem by switch back to the stock length fender, but probibly most importantly by spraying my coils and wire connections with an electrical sealer.
You can do the plug caps and wires as well, and am sure this would help.
New coils or wires may be needed at some point.

Other possability may be if you have pod/individual filters on the carbs. When they get wet, the bike will run badly.

What rstnick said.
If you got shocked when touching the plug wires then that's not right and the rain was shorting things out causing the crappy running. You can spray the coils, wires and plug wires and caps with WD40 which will repel moisture or with an electrical sealer like rstnick describes.
I used to ride in Ireland where it rains all the time and what you described was a common complaint. The electrical sealers work well.

OK, thanks -- I'll look into insulating the coils and wires. Weak spark seems to make the most sense of the symptoms. Sure is running nice this morning now that everything's dry!

Would consider:

Dyna Plug Wires from Z1E

and Splicer if needed

Old plug wires likely deteriorated, cracked and leaking electric charge from coils enroute to spark plug.

And maybe get serious by replacing coils with these:

Dyna Coils

Forgot to mention --

With engine running in complete darkness, use hand water sprayer to spray mist over plug wires, and might get to enjoy a free fireworks display.

Next time it stalls , try opening the gas cap , see if it starts right back up , you might have a vent problem with the cap.

Do you have pod filters?
Seems like I read a post a while back that water on the filters can mess up the fuel/air mix. I don't have pods, and it seems like electrical is the way to go, especially if your getting shocked thru the plug wires.