I read an interesting article by Kevin Ash in a recent edition of Britain's MCM magazine concerning Anti-freeze.

Kevin stated that anti-freeze prevents the water molecules from binding together to form ice in freezing temperatures. This property of anti-freeze degrades over time (2 years) and so the solution must be replaced.

He went on to state that Anti-freeze has a smaller latent heat number than water - meaning that it cannot hold as much heat as water. Water does a better job of carrying the heat away from your engine than anti-freeze.

While the ice preventative properties of anti-freeze are a concern to us that live in California, where it was 70F yesterday, mid January - the heat carrying properties are very important us.
An over rich mixture of antifreeze to water can interfere with the cooling of your engine.

I believe that we are given two ratios to work with for the K-series bike:
1.) 50/50 for cold climates and
2.) 60-H2O/40-AF for warmer climates.

An interesting article - I thought.

Cheers, M

I have just done a Radiator Flush with Wynns Rad Flush and refilled the Radiator with no water and 100% Wynns Chilly Willy Anti-Freeze (Safe for Alluminium Engines) Acoding to the manufacturer by using this product without water it should be good for 5 years ! I think it is possibly what you guys

call Green Stuff ? Should I be comfortable with what I have done or could it be a sales gimmick ?

This subject has been much debated some like alternates some like to stick to using BMW original antifreeze as a safety factor knowing that it is matched to the mix of alloys in our engine and cooling system.

The crunch is how cold can your bike ever get mid winter when parked if it never goes to -30 (and many members on the list do live where it gets that cold and some where it gets even colder still). But if you don't see low temperatures then use a 40% mix of antifreeze to 60% water. Some people where it can get warm like to also put some Redline Water Wetter in as well to reduce the effect of micro boiling that takes place in the engine cooling jackets.
Regards,
K-BIKE

Moto Smith wrote:Kevin stated that anti-freeze prevents the water molecules from binding together to form ice in freezing temperatures. This property of anti-freeze degrades over time (2 years) and so the solution must be replaced.

Could add to this that the anti corrosion additives also degrades over time, and is AFAIK the main
reason why the coolant should be changed at certain intervals.

Inge K.

Ronnie Cantamessa wrote: I have just done a Radiator Flush with Wynns Rad Flush and refilled the Radiator with no water and 100% Wynns Chilly Willy Anti-Freeze (Safe for Alluminium Engines) Acoding to the manufacturer by using this product without water it should be good for 5 years ! I think it is possibly what you guys

call Green Stuff ? Should I be comfortable with what I have done or could it be a sales gimmick ?

Wynns make some good products but are also good at the marketing angle. I would say that the chilly Willy is equivilant to a 50% mix of the green stuff.
The 5 year claim, well under ideal conditions probably but I would be inclined to go he usual 2 years.

It is correct that antifreeze - Ethylene Glycol - has lower heat carrying capacity than pure water. However, tat is not very significant, as the heat transfer properties - moving heat from the engine surfaces to the coolant and from the coolant to the cooler surfaces - are the limiting factor in coling the engine.

A mix of 50/50 or 40/60 water and ethylene glycol has a better heat transfer coefficient than pure water, and is therefore a better coolant.

Biannual flushing and replacement of the coolant is a CYA operation. Hardness in the water can over time settle as solids on the surfaces, degrading the heat transfer. Using demineralized or distilled water eliminates that problem.