Howto drain coolant?

[ladyj]

Good morning,

I have an 01 F4i and it has been running hot and the overflow and really been overflowing. Come to find out, it was straight water and no coolant. I would like to flush it and then add coolant. My question is: do I need to buy the radiator flush (that's used on cars) or is there some special flushing agent?

Thanks so much

[Jason748]

No, you don't need a radiator flush.
But, running straight water won't cause a bike to overheat / overflow.  Sounds like you have another problem.
I'd start by pulling the radiator off and cleaning the fins really good.  Just remember, don't use high pressure (like from a pressure washer) as it can bend fins.  also if you have a bunch a bent fins use a comb and straighten them out.
Next check and or replace the thermostat.

If that doesn't do it you have bigger problems.