Strange noise from the engine suddenly

That is the balancer chain adjustment - the cam chain tensioners are automatic unless one is defective. There are two cam chain tensioners, one for each cam. It could be that you have a bad cam chain tensioner - it may be worth investigating. The tensioners can be manually manipulated with a small screwdriver. Also the balancer shaft chain adjustment can be fairly finicky to get right. If you have tried adjusting it already it may be worth another go at it.
 
For the cam chain tensioners, how can i test them?
Middle screw off, and wind them up clockwise and then release?
I that the way to go?

Repair manual says nothing on this.
 
For the cam chain tensioners, how can i test them?
Middle screw off, and wind them up clockwise and then release?
I that the way to go?

Repair manual says nothing on this.
The tensioners are self-adjusting. Before you go playing with them, the first thing i would do is pull the valve covers and see if one of the chains have excessive slack. If so, you know where to start looking. Manipulating the tensioners, without understanding how they work, COULD end up in disaster.
 
For the cam chain tensioners, how can i test them?
Middle screw off, and wind them up clockwise and then release?
I that the way to go?

Repair manual says nothing on this.
Kevin (@Kevcules) replaced one of his tensioners. As I recall he had a good look at the old one to figure out how it works. Maybe he can shed some light on it for you.
 
The only way you can actually check the cam chain tensioners is to remove the screw plug in the back and insert a small flat screwdriver and twist it to remove tension and then release the screwdriver to make sure the tension tightens up again. It is important that the tensioner snaps back cleanly and does not hang up. Of course you must make sure that the engine is not turned over when the tensioner is loosened up as you don't want the chain to skip a tooth on the sprockets. It would probably be best to remove the tensioner completely to make sure it works solidly and overall you can check the condition of it. If you have a bad tensioner it would be important to take a good look at the plastic chain guides as well to check for excessive wear. The ST1300's are getting old enough now that these chain guides may start getting brittle from age much like other older Hondas did from the 70's and 80's.
 
I have made a new video. Driving in second gear.
It is so loud that my wife can hear it and says that is no good. Normally she does not hear anything different.

I do not know what to do. This is so bad timing. In 1,5 week we are going on a tour for 4 weeks. With this sound and my bad feeling about this. :(

 
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What have you found so far? How was the cam chain tension? Did you remove the tensioners and check them for smooth operation? Have you adjusted counterbalance lash? Have you checked that spark plugs are tight?
 
With the plastic off and the exhaust pipes exposed I would start with the engine dead cold, start it up and quickly feel the rate of temperature rise at every exhaust pipe and see if one is stays colder than than the other three or if two stay colder longer than the other two
 
What have you found so far? How was the cam chain tension? Did you remove the tensioners and check them for smooth operation? Have you adjusted counterbalance lash? Have you checked that spark plugs are tight?

I have placed brand new NGK plugs, the normal ones.
The counterbalance i did not adjust. I have that done last year, just the way Igofar says. He did me a message. How can they produce this sound so suddenly?
Cam chain tensioners i have not removed them. The sound is on both sides the same. They do not fail togheter at the same time?? Right?
I have synchronise the starter valves.

It starts direct. It is not shaking and their is no vibrations at idle, excepts at higher speeds, i can feel a little more vibrations.
I put a coin on his side on the tank and it stays their.
When it starts cold the sound is even more louder. When it gets warmer it goes a little to the background.

Pulling the clutch at idle will not change the sound.

It is not a rattling sound. It is a mechanical sound. You can hear it all the time on the road. It is RPM related.
When I drive and pull the clutch in it does not dissapear. When I pull the throttle open with the clutch pulling in, I can hear the sound synchrone with the RPM.

I think it comes somewhere from the center of the engine. Because both sides sounding the same.

The sound is so loud that my wife can hear me coming down the street. She also hears it when she is sitting behind me. And when my wife is hearing something their is something wrong, because she never hears a different sound.

I have tried to locate the sound with a screwdriver on my ear. But it to difficult to locate it.
 
With the plastic off and the exhaust pipes exposed I would start with the engine dead cold, start it up and quickly feel the rate of temperature rise at every exhaust pipe and see if one is stays colder than than the other three or if two stay colder longer than the other two
I have done that. It is all the same.
 
I have two video`s . One from 1 year ago and one from a few days ago. A year ago their is that typical whining sound. That is gone on the recent video.

A few days ago.

1 year ago


The rattling noise from a year ago was a muffler clamp that touches the center stand.
 
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Listening carefully to your videos, the sound I hear is very typical of a broken, stuck or ineffective chain tensioner, it could be in either side. There is no tension and the chain rattle, not a big deal but the tensioners need to be checked or alternatively replaced.
 
A member from the Dutch facebook group send me two video's.
He said that this sound like an broken bearing from the alternator.

If this is the problem. The whole engine has to taken out?

Here are the video's.

 
For you, I'm hoping it's your alternator bearings. I've never had my alternator out, But here's an excerpt from the factory service manual:

ALTERNATOR

GENERAL
The alternator service can be done with the engine in the frame

REMOVAL
Remove the following:
- Throttle body (page 5-64)
- Radiator (page 6-13)
- Thermostat housing (page 6-8)
Remove the rubber boot and terminal nut.
Remove the alternator connector and terminal eye-let.
Remove the screw and oil pressure switch terminal from the switch.
Remove the oil pressure switch (page 22-21).
Remove the alternator mounting bolts.
 
It is now 9AM and I have taken the fairings away.
Checked the cam chain tensioners, i can turn them clockwise and they spring right out again.
Checked the balancer shaft. Adjusted again like Igofar says.

Started and the noise is coming from the middle i think.
 

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Removed the radiator, thermo house and throttle body.
It was not easy to remove the throttle body. Very stuck on the intake rubbers.

Removed the Spark plugs and want to turn the engine with the rear tire.
Put it in second gear.
Almost not possible to do.
It feels stiff.
Thought maybe to hear the alternator turning.
Is that even possible?
 

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And now i am stuck.
Bottom bolt from the alternator not possible to get it out.
Impossible place for tools.

Anybody that have tips?
 
One hour later, i got the bolt loose. :)

Removed alternator. Bearings from the alternator are good.

I made a video. I am turning the crankshaft by hand.
Listen to the bearings house behind the alternator.
I think this is the problem.
Very bad sound.
I can feel with my fingers on this house a sort of rumble? When i turn the crankshaft.

 
Anybody that can give me info about removing the engine from the frame?

I have not done this before. Their is no shop that have time here for the first weeks.
This is a little bit scary.
 
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