Strange noise from the engine suddenly

PanRider1300

PanRider1300

Joined
May 28, 2024
Messages
93
Age
51
Location
Netherlands
Bike
ST1300
I need your help guys. After a drive with my wife as passenger the engine makes a different noise. Even my wife said it when we stopped.
It sounds like a heavy rumble. It is not the high pitch sound. It is deeper. As if the engine have more difficulty to turn around.
But it reacts good with throttle.

The spark plus are new. Original NGK iridium.
I have changed the coils to test if their is one faulty. Not.
New oil and filter.
All the vacuum tubes are new. Nothing clogged.
I even have the throttlebody synced. I thought maybe to much out of sync. But that was not the case.

I have made a video. The sound is good, but it is not so clear to hear.


Thanks
 
Pull the NGK Iridium plugs out!
There are so many knock off, fake plugs out there that NGK has a page showing how to tell if they are real or not.
I have a large jar of fake/knock off NGK plugs that folks purchased, brought to me to install, then NGK verified that they were not the real product.
IF they are fake, they can damage your engine.
This would be the very first thing I would inspect/check.
 
Thanks for the reply.

The iridium plugs are bought at a local shop here. Not online. The change that there fake is minor. But i have changed them this morning for the normal NGK plugs. No difference at all.
I have made a new video with the other plugs and in cold condition. Idle is higher. The sound was there, but it is difficult to catch the sound with the Phone.


Yes, i have put new gas in the tank. But i don not remember when this sound began. Before or after.
After this weekend, i am away for a couple off days, i will drain the tank and put other gas in it. Just to be sure and test it.

If someone read my other topic. I have no more Bazzaz kit on my motorcycle. It drove perfect, but the milage was bad. With the ridicule prices for gasoline i taken it off.
The motor is now stock setup.

For me the sound is like a boat or tractor. Like, whoem, whoem, whoem, whoem.

It sounds way different than before.
 
PanRider1300 said:
Is the strange sound hearable from the video?
Click to expand...
I hear it. I assume it makes no difference if the clutch is in or out?

Have you adjusted the Backlash Adjustment on your Crankcase Balancer? It is located at 12-12 in the Honda Service manual. It has very specific adjustment procedure but the end statement says:
"If the gear "whine" noise is excessive, the backlash is too small. If the gear "rattling" noise is excessive, the backlash is excessive."

This adjustment is at the front of the engine, so relatively easy to get to. I had a slight rattle on idle when I bought mine, I adjusted it and it was fixed.

Good luck! I hope you find the issue quickly.
Ryan

Edit to add pages:
1777126302824.png
1777126334306.png
1777126358700.png
 
Igofar said:
Pull the NGK Iridium plugs out!
There are so many knock off, fake plugs out there that NGK has a page showing how to tell if they are real or not.
I have a large jar of fake/knock off NGK plugs that folks purchased, brought to me to install, then NGK verified that they were not the real product.
IF they are fake, they can damage your engine.
This would be the very first thing I would inspect/check.
Click to expand...
I was just wondering what are the alternatives to the NKG iridium plugs. Does Denso make a similar plug? If they do, what part number?Are they prone to have the same problem with fake knockoffs? You really have to pay attention now days.
 
@Ryan_B

The sound is indeed the same clutch in or out.
The adjustment of the crankcase balancer is already done.
It is also not the whining noise.
I think it is not good to hear on the video.
It is a heavy sound. If the motor has more difficulty to turn.
And more rattling noise also.
 
PanRider1300 said:
@Ryan_B

The sound is indeed the same clutch in or out.
The adjustment of the crankcase balancer is already done.
It is also not the whining noise.
I think it is not good to hear on the video.
It is a heavy sound. If the motor has more difficulty to turn.
And more rattling noise also.
Click to expand...

You might try to use a long screwdriver as a stethoscope (touch whatever part you want to listen to and place you ear on the handle).

Since it was a sudden change, and is a constant noise. I would be looking at anything that spins like the alternator and water pump.

Ryan
 
Have you looked for coolant leaks out the weep hole? Your water pump mechanical seal may have given up the ghost!
Also, if you removed any body work, check the wire harness behind the left worker if the radiator, if you didn’t get it back I. The proper place, the radiator fan shroud spinning could be hitting it.
 
PanRider1300 said:
Have i used the wrong translation?
Vacuum hose or vacuum line. Is that better?
Click to expand...
Hose or line would be more common here. Hence the joke about vacuums tubes. That what we call the devices found in old TVs and radios or high-end audio equipment etc. The Brits call(ed?) them valves.

A tube could mean vacuum tube as in above or something larger in diameter than a hose or line like that found in some tires or hamster cages. Hope that clears it up. :)
 
Oke, all fairings off. Finding a small coolant leak. Not from the weep hole.
But from the bottom of the thermostat housing.
Aaarrgghhh. Two years ago i replaced the thermostat and used a new oem O ring. Just to avoid this.
But that is not the strange sound.

The rubber hose on the left is little flat on the corner. See the photo. That is not good for the flow. Or is it oke?
 

Attachments

  • IMG_20260427_211905.jpg
    IMG_20260427_211905.jpg
    83.4 KB · Views: 32
  • IMG_20260427_211919.jpg
    IMG_20260427_211919.jpg
    115.8 KB · Views: 33
Great hearing. It just sound like that.
No, i have not adjusted the cam chain tensioners.
What is the good way to do that?
 
You must log in or register to reply here.
Back
Top Bottom