I just did some maintenance to the F4i- including draining its coolant from the radiator and the block. I unbolted the drain plug at the lower bolt on the water pump and on the engine block behind the exhaust header. Anyway since it's been a while since I've did a complete dumping of the fluid I think I got some air into the unit. The bike when it gets to over 180 degrees F and at idle speed it has a high pitched squeal to it, which goes away when the engine is revved (even a little). Sounds almost like a supercharger on a hot rod

Since then I've burped the system 3 times but now the squeal has gotten better but still does it after it warms up. I'm good with auto-mechanics but I've never experienced a water pump going out on a motorcycle, nor do I know how long they should last. The cooling system does not seem to leak. But any time there's funny noises, it causes concern. Does this sound like the water pump is on its way out?

I haven't used a mechanic's stethoscope yet but I'm pretty sure it's related to the water pump based on the symptoms (does it only when hot, just changed the coolant). I should mention the bike is 11 years old. I'm the original owner and it has 51k miles on it.

 

You found the problem? My f4i making the same high pitched sound

 

@reaim It is unlikely that you're going to get a reply from @CBRc5eric since his post was from 2012. He did love his F4i and it was his first bike, but probably moved on. Create a new thread on the forum and maybe you'll get some help.