Example of “Toxic Sweat”
 

We have many similar stories at our shop as well....

That is nasty!! Has to have a zillion hours on a trainer, or is this simply from road riding?

And this is why you change your bar tape every 2-3 months kids.

When I lived in NC (Raleigh) and I would return from a ride I would leave the bike outside for a little while to dry off the sweat. The bikes were in our ACed basement yet the next day the bar tape (Cin cork) would be wet, the salt drew moisture out of the air. We (Allstar Bike Shop) saw a lot of salt damage. Too many stems and posts fused in place... Andy

Another reason for carbon fiber handlebar.

I’ve never heard anyone suggest rewrapping so frequently before.

And most don't need to if their conditions are more "gentle". But there are some who just sweat battery acid and those do need to keep up with the damaging consequences of corrosion before the part breaks, gets frozen in place or the corrosion wears mating parts. Andy

Would you rather spend $20.00 on tape or have your bars break? If you sweat a ton every couple-few months is good, if you don't sweat or at least don't sweat battery acid you can obviously go longer.

I usually live in the desert but I wrap my bars almost that often, I get bored and need more flair.

Would it make sense to pre-wrap the bars with packing tape or plastic wrap before the bar tape?

I think profuse sweat would still seep through.

OP is in Tampa, Florida; perhaps the humidity also contributed to the corrosion.

On the trainer I have hand towels draped over my bars, stem, and top tube for this reason, not-so-much when riding it outdoors. I haven't replaced my original bar tape in 18,000 miles, but after seeing this I'm at least considering it.

No.

Not carbon but chromed steel bars!

I can tell you that it's not just the handlebars that can be ruined by "toxic sweat." The insides of integrated shifters/brake levers, headsets, seemingly every bolt on the bike, front derailleurs, bottom brackets, cables, cable stops, chains, wheels, and last, but not least, the frame itself. It's a troubling phenomenon, from a bike shop perspective. We love and appreciate our customers, and sometimes it's the ones who love to ride the most who absolutely destroy their bikes because of this. It's not an easy thing to explain, even though, as a bike shop employee, you've seen it many times before. No one who loves riding wants to be told that they are going to destroy their bike with their own sweat, simply by riding the bike. But in extreme cases, this is absolutely true. And no amount of added maintenance or precautions, within any sense of reason, will change that. I have often wondered if there are medical issues/remedies that could change it, but it's a sensitive subject with some, and I am not qualified in any way to give medical advice anyway, so I'll leave that to medical professionals. But I know for a fact that "toxic sweat", as the thread title says, can completely destroy the bikes of those unfortunate riders who produce copious amounts of this type of sweat.

I wonder if silicone bar tape will protect the bars against this? I think silicone is generally closed cell and water-tight.

Mountains are turned into plains from water getting into the tocks. Bearing seals leak. And water finds its way down stems and posts. To deny reality is to mislead yourself and any one depending on you. Andy

Just WOW.
What about simply washing the bike/bars and a good spray lube in the shifters, etc?

Yikes. Never let xenomorphs ride your bikes. Their sweat is almost as bad as their blood.

I have an old set of Dura Ace 7400 STI shifters almost that bad. I bought 'em used cheap just to cannibalize for the internals if necessary to support a good set of the same shifters. The previous owner may have been part xenomorph too.

If I drink electrolytes during a ride my sweat will cause a few rust spots on one of my stainless steel pocket knives, but that's pretty unusual for me. Usually my sweat is pretty inert and I've gotten away with neglecting stuff for years and it's been fine. I've seen other people's sweat disintegrate their clothing and shoes within a few months.

No.

Although I've seen a number of frames fail from sweat and stems seize into the fork, I'm never seen a handlebar fail. Some were fairly corroded but never a failure. That's some toxic sweat.

Nope. Not chromed. Chromium has the same problem as iron and aluminum with salt.

The salt is only part of the problem. The humidity and dew point are the other part. Here in dry Colorado it is currently 35°F with a relative humidity of 45% and a dew point of 20°F. Current temperature in Tampa is 70°F with a relative humidity of 89% and a dew point of 69°F. There’s no water to sucked out of the air in Denver while there is lots and lots and lots of water to be sucked out of the air in Tampa. Sodium chloride is hygroscopic which means it can suck water out of the air. Your bar tape in NC wasn’t wet because it failed to dry but because the salt in the bar tape was actively sucking water out of the air.

When the salt has access to water, the interesting stuff starts to happen. Aluminum and iron are reactive metals (iron a bit less than aluminum). They are particularly reactive with chlorides. The chloride iron can react with the aluminum or steel to form a aluminum chloride or iron chloride. Both of those chlorides are unstable and will readily give up the chloride ion for an oxygen of which we have an abundance. The iron oxide and aluminum oxide are very stable but not very strong. The chloride ion is released to go back and pick up more base metal. As long as there is water to serve as a vehicle, this will continue until there isn’t any metal left. Your steel parts will be come iron ore and the aluminum parts are now bauxite.

This also happens with chromium, by the way. It’s slower but it goes through a similar mechanism.

We don’t see as many salt corrosion issues here in Colorado (and Intermountain West) as in other places. There’s simply not enough water in the air for the salt to suck water out of the air to keep the corrosion process moving along. We salt our roads in the winter but we really don’t see the rust problems in cars that other states see.