Engine noise!!

[XJ600N]

Hi I bought a XJ600N last week but found that there is a noise coming from the engine. I am not sure if this is Piston slap or valve noise. I am very interested in my bikes engine and would like to sort the problem myself but I don't have a lot of knowledge about this motor since this is my first big bike.

The bike runs fine without any issues and the gears is smooth with no slips and no smoke coming from the motor either. The noise is loud when the bike idels but once the engine gets running the noise disappears. I did find that the oil level were very low when I collected the bike. I have since toped it up with oil but the noise is still there. Will this harm the bike if I keep using it like this or would it be ok until I can manage to get it sorted?

[Frost]

Low oil levels have helped the top end wear. The top end is where all the friction takes place and is the first place damaged by low oil levels. The wear at the top end has increased valve clearances letting things have more room to move about and make more noise. When warn these gaps will close making it quieter. Get the cam cover off and measure everything using a digital caliper and feeler gauges. Replace shims as needed. They often cost about £4 each, maximum number to be replaced is 16. A garage will charge about £350 to do this.

[Casper]

I am sure the XJ is only a 8 valve engine however what he say is true. You may just have a lose or worn cam chain or the clutch could rattle. My money on the cam chain. Look at ajusting it if its fine then go for the valve shims.

[Frost]

Yeah it is only 8 valve. Pretty sure my Pre-diversion one was 16.

[Vincent]

You can often get a better idea of where the noise is coming from by using something as a stethoscope. There is a propper automotive stethoscope available but I use a large screwdriver. Stick the tip on various parts of the engine, ie; the cam cover or clutch cover, then put the handle in yer lug 'ole and listen out for localised rattling and/or scraping noises.

[Robby]

Does the noise get quieter if you pull the clutch in? Could be a bit of clutch basket rattle, which is nothing to worry about.

Worth doing an oil change before you pull the engine down too, using the correct grade of oil (probably 10W40) and a new filter. Get the engine good and hot first so the oil drains well, and see if the noise goes away or gets quieter after 100 miles or so on the new oil.

[Walloper]

I'll defy anyone to identify what is the cause of noise using screwdrevers or stethescopes or divining rods et al.

Unless you have prior knowledge of what you should be hearing from an engine under normal conditions and or an engine sufferering the ravages of time/abusive operation it may only lead to confusion.

It may give an indication of where but even then the noise of one part can be amplified in a completely different area.

On larger machines this will work on small motorbike engines it's normally worthless.

As suggested above, elimiate the cause/s of noise if possible. Pulling in the clutch.
In gear slowly let the clutch out to biting point.
In gear running on centre/paddock stand.
Think of ways to test before wheeling it into theatre.

Open up the oil filter for a shoofti. Look for evidence of failure.
If it's critical then there will be debris from active problems.
If it just wear then there will not be much to see.

It may mean opening up the engine to measure and evaluate.
If something is broken you will find it then.
Unless you know someone who has 'intimate knowledge of the beast of course.

I would expect piston slap noise to be accompanied by lack of power, poor cold starting and really bad oil consumption.

I wouldn't worry too.... much about the low oil. Unless you had to top up by about 50%. A lot of folk never bother to check oil regulary and so may need a top up of 20% when they do.
I have a pre-Crimean War Massy Ferguson in my bike which uses more oil than a chipvan but I know this and check it regulary anyway.
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W-ireless A-rtificial L-ifeform L-imited to O-bservation P-eacekeeping and E-fficient R-epair

[0l0dom0l0]

sounds like the clutch basket to me. if you pull in the clutch does it go awa? (after it has been ridden)?

[Vincent]