Here in Austin, I've had coolant dumping out with what was a reasonably maintained 50/50 system. Of course, that was with extensive idling (trying to keep a battery up). Since then I've changed to what's been called SiSF's Coolant Cocktail. I had doubts about it, so Steve and I discussed it on the old forums, I emailed the guys at RedLine, etc. Gotta say, I don't think the RedLine guys are snake oil sales guys.
I'll say up front I like the stuff. I just get the feeling (no data) I'm cooler with the stuff in than without. Might be all between my ears, but that's ok. It feels cooler there now whatever the reason
How's it work? Mostly it's from changing most of the coolant from anti-freeze (AF) to water (H2O).
NOTE: The numbers in here are from memory. I didn't go look 'em up again. Double check everything. Do your own math. Ask questions if you can't figger it out.
H2O will hold more heat per volume than nearly anything, and it takes and gives it up more easily too.
AF will lower the freeze temperature and increase the boiling temperature depending on how much a percentage of it's in the coolant. Quality AFs also have corrosion inhibiting chemicals in them. These are what make one AF incompatible with another. AF doesn't hold or transfer heat nearly as well as H20. AF is also slippery as hell. 2nd gear, or even 3rd rolling 'burn outs' are difficult to avoid once your rear tire gets wet with the stuff. The bike still has a weird spot in the seat from that . . .
RedLine Water Wetter (RWW) isn't anti-freeze. It's mostly a 'surface tension modifier'. What that means is the bubbles that form inside a normally operating engine, aka steam pockets, are smaller with the lower surface tension. Unlike the snake oil stuff out there, RedLine has data and SHOWS it! They answer questions! RWW also has corrosion inhibiting chemicals in it, replacing or renewing the stuff in the AF. It doesn't take much to protect the entire cooling system.
So what's The Cocktail? SiSF didn't invent it, but he's the most recent to make it popular with Concours riders. Here's my take on it. Look at the table for your fave flavor of AF. Put enough AF in the system to protect from freezing in the coldest conditions you imagine you'd have the bike in. Here in Austin, I don't worry about it since if it's near freezing the bike it in the garage. I put very little if ANY AF in. Then put in the RWW as directed (4oz?). Top off with distilled or at least de-ionized water. It's cheap at the grocery store. DO NOT use tap water, even the 'softened' stuff - maybe unless it passes through an RO filter first
If you need to put more than about 30% AF in, save your money and don't use the RWW. It will still help, but if memory serves it's less than 10F instead of as much as 30F for 0% AF. IMO not worth the extra expense or hassle.
Temp gage runs lower, comes down faster when rolling after getting hot at a light, etc. I think since this mix gives up heat more quickly everything else, including me, has less chance to get hot. Also I think the fan runs for a shorter period until it cools enough to turn off. That helps too.