After getting her up to around 160kph for the first time it now seems like the knocking noise (that was already present) has become more pronounced - clearly audible at idle. It seems to come from low down in the block and is most audible from directly under the oil pan. My first thought was big-ends... but a mate suggested it could be due to oil starvation, possible a blocked oil passage / oil filter?? Hell maybe even the oil pump...

What lends his theory some credence (I think) is that if the bike has been sitting for a while, the knock only starts a couple of seconds (um... 4?) after starting. Kinda like oil is settling somewhere, but then is not getting back there after the engine starts. The noise may also *possibly* be coming from where I think the oil pump is... but I need to check this.

The oil level looks fine going by the window.

I can feel the knock through the chassis... but haven't been able to clearly identify the source with the 'stethoscope' method.

Any ideas?

It sounds like one of those jobs that should be done sooner rather than later.

Heh heh, yeah... she's just sitting in the garage for now

have a look arounf for a 600 3HE engine just in case

Hi,
you sure its not the exup rattling around in the exhaust? Your good trundle may of cleared the soot out from around the bearings. Maybe worth a look before you start taking the engine out!
Cheers
Ian

Thanks but nah it's not the EXUP, I've just given it a make-over... the noise is coming from inside the crankcase.

This morning I also checked if the noise changed when the clutch is in or when she's in gear. Also checked if it changes when there's a bit of load on the motor (i.e. in 1st gear and released clutch enough for it to bite a bit)... didn't hear any change.

Sounds like the engine is going to die to be honest. Have you checked the oil - drop it out and see if there are any metallic flecks in it?

oh my word... Morespeedvicar I owe you a beer or 2, I guess I'd convinced myself it had to be something bad

I totally dismissed your suggestion about the EXUP... but it just sat there at the back of mind... I just checked and it is the farking EXUP valve. Some play has built up in the cables and it's just rattling away in there, I can hardly believe it... it is SUCH a regular sound you'd swear it was something attached to the crank...

:D

That's cool - I bet your a happy man now

Remember adjust the cables to be finger tight only.