Can you diagnose this?
 

Im trying to find out what it wrong with my xt600z, so I have recorded 12sec of sound. Its .mov, quicktime, so I hope you can hear it and maby tell me what it is? Some knocking. I think it has a Wiseco piston, and some say it will make some noise, but that it is harmless..

Now lets just see if Im able to post the file...

Well, finally converted it to mp3...Attachment 3139

Could you post in another format? mp3 or even wave...

Believe me, Ive tried... even downloaded new program to convert the file, but no, couldnt do it..."Unable to open" it said.. Tried to post it via youtube too, but all I got was an error message.. It works fine with Quicktime, so I dont know why it cant be converted...

afterall VLC media player plays quicktime! ;)
I'll hear the clip a few times and I'll post back if I think of something!

Mate.. I believe you have a little work to do on that engine... it could be a few things.

I don't want to say anything bcoz I am not sure and don't want you to get paranoid....

What I would do is:

check your engine compression(it should give you an idea on the state of your piston and piston rings)
check the valves gaps and camshaft chain

but that noise.... it sounds like a bad crank bearing or some loose nut inside the engine....

I suggest you to check everything first and not ride the bike at all... :funmeterno:



Vando

Well its been like that since I got it, and Ive driven 2-3000km on it... sounds a bit worse on the pc I guess.. I had my Iphone close to the cylinder when I recorded it. Sounds like it comes from the top end..

Oh... now that explains a few things lol...

do the compression test and after that check the valve clearances!

How many miles or km does the bike have?

Thats a KNOCK more than anything.

Does it go away when "blipping" the throttle? More or less when under load?

Loose counter balancer?

It only has 30000 km on it..
The knocking is not so bad when I twist the throttle and put pressure on the engine

little end bearing is no good causing the piston skirt to scrape the barrel :thumbdown:
top end rebuild at least depending on how long and what oil contamination has done to the rest of the engine :thumbdown::thumbdown:

Hmm, thats no good I guess... Whats the "little end bearing"? Sounds like a lot of work. Never done that before. Well Ill better hit the garage and start. Is there any good online descriptions on how to do the top end? Preferably with pics?

Little end is the Gudgeon pin or wrist pin that hold the piston to the conrod - connected to the, crank shaft :innocent:


Not sure its that, especially if it goes away when loaded ?

Yep, you best take the head off and investigate

Difficult to diagnose without hearing it from different areas of engine using either the "long screwdriver with the handle in your ear" method or if you're posh, a stethescope(sp?).

Does the noise diminish or increase once the engine is warm ? or when under load ?

I would make sure your valve clearances are within tolerance as a first step but as said by others I would suspect piston slap. Should get away with a cylinder hone, new piston and rings and small-end bearing.

Well now Ive started to take it apart. Checked the valve clearanses; loose 0.10mm on exhaust, bit tight on intake so I adjusted to a tight 0.10mm.
I have a Clymer for the XT, so Im going for it.. more work than I thought, lowering the engine to get the top off, and its all so #¤% TIGHT...
Ill keep you informed on the progress, and thank you all for good help :-)

Det runde lageret (foringen) som er presset inn i enden av råden (mot stemplet). Pinnebolten (wrist pin) går gjennom stemplet og gjennom lageret og fester dermed stempelet til råden.

For å sjekke slakk må du ta av stemplet, sette pinnebolten tilbake i råden og kjenne om det er slakk. Ofte kan det være pinnebolten som er skadet, den kan få en lett timeglassfasong.

Skal du av med toppen er det ikke mye ekstra jobb å skjekke dette,