HELP ! EXPENSIVE ENGINE NOISE.

[ducmeister]

Hi all,

Over the last few months my bike has been making a few weird engine noises that have gradually been getting worse.  At first it was just a bit of a whine at around 100kph but in the last few weeks it has become a whirring noise at all engine speeds and a distinct howl at about 3500rpm.  This howl has come on rather quickly. 
At first I thought it was just getting a bit noisier with age but the noises now are concerning me greatly.
I took it in for it's 30k service on Tuesday hoping that it was loose belts or something like that but it is still not right.  They have also disconnected the alternator and pulled the clutch to bits to eliminate those possibilities.  They are now saying that the next step is to strip down the engine to check bearings.    $$$
The bike is still in the shop.
Any ideas would be GREATLY appreciated.

Cheers,
Rob.

[heatherp]

She's lamenting the fact that you don't ride her enough.   

Sorry Rob can't help - I only have experience with wheel bearings 

I'm sure members with heaps more experience than me will be more than ready with suggestions for you. 

Cheers   

[ducmeister]

She's lamenting the fact that you don't ride her enough.   

Too true.  It often concerns me that even after a long stint without a ride it fires up straight away without a chance for the oil to get pumped around a bit.

[dragonworld.]

I assume that they checked the cambelt tensioner bearings??

And have done an oil pressure check?? 

[DUCMONROB]

Does it make the noise when the bike is in neutral?

Any specific gear?


More details needed.

Rob

[brad black]

without hearing it it's impossible to know.  i've heard mains rumble and also whine like an old roots blower.  if you pull the clutch pack it removes the gearbox, and if it's still there then you've got crank and heads.  you could try one belt off at a time, but i'd say it's mains if they've done the clutch bit.

most of the ones that i've had run big ends end up with about 40psi on the gauge, but with the gauge rapping wildy from 30 to 50 sort of thing.  we had one that ran for quite a long time for run big ends, like a few weeks.  surprised hell out of me.  oil light still went out like normal.

ultimately there's only one way to find out, and that's strip it.  what else are you going to do, apart from stomping around in a bad mood and kicking shit?  if it is mains you can knock the centre out and all the balls fall out and you can look in there.  i've seen them have a spot where the outer or inner is all pitted and the rest fine.

[ducmeister]

I assume that they checked the cambelt tensioner bearings??

And have done an oil pressure check?? 

Yup.  I think they may have changed one tensioner bearing.  
As for the oil pressure, I'm not sure but the oil pressure light behaves as it should.  Might ask about that one.

Yes, it makes the noise in any gear including neutral.  It changes with rpm but doesn't change if I just operate the clutch or put it in gear.  They are thinking that it's something in the primary drive ie a crankshaft bearing but not a big end as it doesn't seem to be knocking.

This is not what I expected after just 30,000km.

most of the ones that i've had run big ends end up with about 40psi on the gauge, but with the gauge rapping wildy from 30 to 50 sort of thing.  we had one that ran for quite a long time for run big ends, like a few weeks.  surprised hell out of me.  oil light still went out like normal.

Hey Brad, pardon my ignorance but I'm assuming you're talking oil pressure here?
I guess you're right .  I'm clutching at straws a bit.

[ducmeister]

 i've heard mains rumble and also whine like an old roots blower.

Funny you should say that.  My description to the guys at the shop was that it sounded like a supercharger but not so loud.

[heatherp]

This is not what I expected after just 30,000km.

Strange things seem to happen to Monsters in Victoria at 30 000km.  Like collapsing wheel bearings.  Must be all the wet stuff down here - they really are sugar cubes.   

[dragonworld.]

They replaced 1 cambelt bearing?? Duh!! 

I would think that if one has carked it good policy would be to change the friggin' lot?? 

Hmmmm.

[loony888]

i would have had all the tensioner bearings done if it was me, did they check the alternator nut? they come loose on late 4 valvers, not sure if it's an issue on the 2 valvers.


paul.

[monsta]

did they check the alternator nut? they come loose on late 4 valvers, not sure if it's an issue on the 2 valvers.


paul.

thats what I was thinking...  It came loose on my 748, it was more of a knocking/clutch rattle noise tho. but maybe get em to rip that cover off and look before they drop the engine out...

[ducmeister]

thanks all.

[ducmeister]

Hey guys, having real trouble posting.  It's like I'm not logged in but I am.  Weird.

Thanks for your suggestions.  I'm going to give the shop a call now.