http://www.youtube.com/watch?v=6UevsUVxQgg" onclick="window.open(this.href);return false;

Taken on my phone but it shows the noise quite well. Sounds like a tractor!

Fairly loud rattling noise somewhere on the LHS, seems to be low down, somewhere around where I'm pointing the camera (you can hear the rattle get louder/quieter as I move the phone). Loudest at tickover, changes speed with revs but can't hear it at higher revs.

Any ideas?

Ahh you may have saved me a bit of time recording that sound as my bike is suffering the same simptoms..

any ideas guys?

Adam.

tractor eh? I cannot get on this at work..but the last bike I had that was a tractor was flogged for scrap asap

that doesnt sound good at all.

or....now this is just a theory,

you have the only ever deisel cbr 400 engine honda ever made. the only ever deisel honda fr that matter.

just trying to give you the good and the bad

its like one of the piston is not properly functioning.

My problem sounds similar to what wig had, as he describes in this thread: viewtopic.php?f=28&t=13338&p=91563&hilit=rattle#p91563" onclick="window.open(this.href);return false;

So I might whack the cover off and check the cam bolts.

Although having said that, my rattle is low down. Damn

I havent watched the video but you have checked that there are no holes in the exhaust, as a blowing exhaust sounds terminal.....

I'm pretty sure it's not the exhaust but I will double check, if it is that would be a big relief.

The rattle is loudest at tickover, gets quieter as the revs pick up and can't be heard above 2,500rpm.

Sounds like it's coming from within the LHS engine cover, or further within the engine, but definitely to the left side and definitely low down around crank height. So could be a crank bearing gone?

Exhaust header on cylinder 1 doesn't get hot at tickover, don't know if that's related. Has always had this problem though.

Just listened to that - it sounds fecked. Nasty noises indeed.

I'd get looking to drop the oil to see if there are any bits in it - brass coloured for shells etc - or get a spark plug out and see if you can spy the pistons at TDC through the holes - turn it over by hand and see if you get a nice whoomp sound that you get (if you get me)

As billy says, exhausts that are loose can be a ticking...but that is a clacking noise to me...nasty