Sludge in the coolant reservoir
 

Change the coolant in your VTR. Please.
More years ago than I care to admit I put a long-life Dexcool spec coolant in my Firestorm. No silicates. Nice colour. Looked great.
As time passed, I found it more and more difficult to determine the level of coolant in the reservoir. I thought it was just because it's dark between the cylinders. Say what you want. Your reproaches are nothing compared to those I've already directed at myself.
I eventually got around to changing the coolant. It looked OK when I drained it from the radiators. The radiator cap was gunked up with reddish-brown sludge but I cleaned it without difficulty. I removed the hose that goes from the right radiator to the coolant reservoir to drain the reservoir. I expected a nice healthy flow of coolant to come forth. All I got was a very meagre dribble. My bike had an enlarged prostate. Great.
Better diagnostic procedures enabled me to discover that the interior of the reservoir was coated with a thick layer of sludge. The coolant line was blocked with sludge. I had let my VTR down.
I cleaned the reservoir with a bottle brush and a lime, calcium and rust remover. That and a good flush with hot water restored the pristine appearance of the reservoir and cleared the line. I couldn't see any sludge in the radiators themselves.
There's a division of opinion on the Internet regarding the quality of Dexcool coolant. I don't want to get into that here. The thing is that I just left it in there too long. The bike wasn't showing any sign of overheating and I didn't have any special reason to remove the fairing. I'll change the coolant every two years from now on.

Did you mix it 50/50 with distilled water, or any kind of water for that matter, when you installed it. Pure coolant will turn to jello with time. That can also happen over time if you top off with pure coolant.

Also, I know that worn out DexCool smells like a bucket of dead fish.

Yes, I had mixed it 50/50 with distilled water and the recommended amount of Water Wetter and I had flushed the system before filling it.

G05 is pretty good stuff, as well as pentosin and the yellow mic-all stuff that you can get (prestone i think). I have seen nothing but issues with dexcool ( it seems to last even less time then the green stuff), and the green stuff tends to end in corrosion if left for over 3 years.

I think the key to all of these is just changing it more often than you would expect.

Thanks A-teach...very succinctly stated to the point!

I wondered about GO5 coolant. It's described as "low silicate". I don't know at what concentration the amount of silicate becomes critical.
Maybe I'll just put an end to the adventure and buy coolant from a Honda dealer.

It's only $5 a quart from the dealer, and it takes 2 quarts. So 10 bucks every 2 years is no big deal.