Coolant-antifreeze selection for SV

This is intended as a work-in-progress to help everyone make informed decisions about the deceptively simple (yet notoriously problematic) area of engine cooling. In particular, it is a good reason to learn what is circulating in the rubber veins of your bike, keeping your engine from cracking.

Below is a table of common coolant-antifreezes available in UK with their key features:

Blue or green can indicate IOT (old) coolant technology, whereas amber, red, pink, yellow usually implies OAT (newer).
EG - ethylene glycol; PG - propylene glycol. They form the base of a coolant as both the blending agent and freeze protectant. EG degrades over time to glycolic and formic acids, so annual check of your coolant (ideally with refractometer) will give you a good idea of the state of your coolling system. EG is recommended for SV650s (toxicity warning in SV650 Owner's manual; Haynes manual).
OAT or Organic Acid Technology-based coolant should be silicate- and phosphate- free (with some exceptions) and in general should be aluminum-safe. IOT or Inorganic Acid Technology is older, whereas HOAT or Hybrid Organic Acid Technology is OAT with addition of silicates and other things from IOT repertoire.

Brief IAT constituent purpose descriptions:
Silicates (IOT/HOAT) form a layer between metal and the liquid coolant to protect it from corrosion, but they also deteriorate water pump seals (therefore banned in Japan)
Nitrite-inhibitors (IOT) are used to control corrosion, but deplete rapidly and must be replenished on a regular basis.
Amine-inhibitors - similar to nitrite-inhibitors control corrosion and get depleted.
Borates - water softening agents (similar to phosphates)
Phosphates are used to soften water. In the case of hard water, they react with calcium and magnesium to form a crust on the metal surface, impeding heat transfer (therefore banned in EU)

Manufacturer-provided technical data sheets or websites if TDS were not available were used as sources of the information in the table.

Warning Rock oil has a batch of Kool XL floating around with incorrect IAT labels attached. Please make sure that the rear label says OAT instead of IAT.

Further reading:
http://www.machinerylubrication.com/...t-fundamentals
http://www.carbideprocessors.com/pag...e-coolant.html
https://wiki.seloc.org/a/Organic_Acid_Technology
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[Craig380]

Interesting, thanks.

For what it's worth, I asked the Suzi main dealer I bought my K6 from which brand of coolant they used (the bike had had a oil/coolant/valve check service as part of the sale), in case I needed to top up etc.

They used Rock Oil Kool (the green stuff), but were also starting to use the Kool XL red OAT coolant in newer bikes.

I have used Halfords Advanced (OAT) for years, in all my bikes and cars, with no issues whatsoever.

[SV650rules]

Originally Posted by andy650

I have used Halfords Advanced (OAT) for years, in all my bikes and cars, with no issues whatsoever.

+1 so have I

I always use premixed 50/50 as well, bear in mind that below and above 50% dilution and the mixture will freeze early so with antifreeze more is not better, you will get more anti-corrosion protection but freezing will be compromised. Use silicate free as well, as silicates can damage water pump seals.