Coolant System Flush

I just drained my coolant and am wondering if I should flush the system with Prestone flush or just plain deionized water. The bike is a 2007 and the coolant is likely original so a good flush is in order.

flush with the deionized water, let it get to temp, then refill with coolant.

Edited by DEMI

My plan was to flush with Prestone Clean and Flush (, then flush again with DI water, then freah coolant. Just want to be sure it's okay to use the Prestone cleaning/flushing product. The description says okay for all cooling system metals, but I want to be sure it isn't too agressive for using in a dirt bike. I'm sure it is probably fine.

i don't know about using it for a bike, probably fine, but also probably not needed. I think most only flush with distilled water. New coolant is a good idea however.

Distilled water and vinegar, 50/50 mix, followed by by a flush with distilled water only, then refill with coolant of choice.



i don't know about using it for a bike, probably fine, but also probably not needed. I think most only flush with distilled water. New coolant is a good idea however.


And I use distilled water when mixing new coolant, available at Walmart for about $0.70/gallon.


IMO important to flush when changing type/brand of antifreeze.


Vinegar is a mild acid and does a good job of cleaning, the acid becomes even more reactive when heated.

I'm aware of the vinegar technique, but I'm asking if it's okay to use the Prestone Clean and Flush.

if it says safe, then it probably safe.

Can't see why it would not, but I've never used it in a bike myself.



IMO it take a pretty gross and dirty cooling system to need a chemical flush treatment like Prestone. The most likely place for sludge to develop is near the filler, if I can't find sludge there I figure no need for a chemical flush. 

If there are only signs of light sludge try the vinegar flush first.

For me a normal water flush followed by a distilled water flush is all that is needed if changing antifreeze brand/type.

I did the prestone clean and flush followed by DI water flush, then refilled with 50/50 ethylene glycol mix. I didnt see any discoloration after the prestone flush so apparently there wasnt any crap inside the cooling system.

better go ride tomorrow!

better go ride tomorrow!

Huh? I hope to.

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