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Ringing noise

5K views 28 replies 16 participants last post by  VN750Rider/Jerry 
#1 ·
For a while at exactly 3000rpm I was getting a ringing noise, like a loose washer on a bolt. After a few hundred miles the sound moved up to 5000rpm. Doesn't change with the clutch applied/released or moving/stationary.
It sounds to be from the right side of the bike. I removed the tank and resecured everything but the noise still happens.

The oil screen didn't have any debris and the oil sample returned normal other than slightly elevated iron, which blackstone said is likely from the shared gearbox.

I have the ACCT rebuild kit coming from TOC hoping its just a stuck cam tensioner. Is there another source I could be missing?
Primary chain? But I think the noise would change ringing RPM with the engine loaded or unloaded.
 
#20 ·
Funny, I had a similar noise. it wasn't from the plate itself, but from a washer that was too loose to do any good anyway. It had really been bothering me during rides (not a great time to troubleshoot exactly where a noise is coming from), but when I was back there doing something, I hit the license plate and realized it was that stupid washer.

Off it came! And I haven't looked back. I sure am glad I got rid of that noise.

I still have a little rattling from my gauges, but I've worked around that by riding with my helmet that has a little more padding around the ears :)
 
#3 ·
I have the same noise. Except mine sounds like it may be on the left side. I suspected my crank case breather filter, I wrapped it in a rag yesterday to see if the sound would go away. I'll find out this afternoon. I've watched the videos about the ACCT being broke, and mine doesn't make that noise at all. Can't even make it do it when I'm parked, only while riding.
 
#6 ·
It does it any time the engine is around 5000rpm no matter moving or revving in neutral. I've put my hands on everything but I can't hear exactly where its coming from. Not the keys, I can hold onto them and the noise doesnt change.
 
#7 ·
Get a stethoscope

:doh: my bad
 
#9 ·
I had a ringing noise for a while too, but it went away.
Then i realized my gremlin bell was missing....doh!
 
#12 ·
Mine wasn't quite that noticeable. But I did figure mine out, it is/was the gas tank mount on the left side, the washer vibrates against the tank lip. I could hold pressure on it and it quits. Yours sounds very distinct, almost like a piece of sheet metal or something small tinging.... Hmmmmm....
 
#13 ·
Its absolutely not the key, or anything I can put my hand on topside. Tank mounts are secure. I have driven without the dash panel so its not the gauges either.

I haven't run without the gas cap, maybe the key mechanism is doing it.
 
#15 ·
couple of things to check:

Right side brake lever - vibration causing the inside shoe guard to contact the exhaust possibly.
Heat shields
Front Brake cables vibrating against the handlebars or cluster...same for clutch cable

Rear brake cable rattling in the area of the coolant bottle.
Rubber stop missing on center stand...vibration causing it to "ting"

Throttle cables routed near the right side of the frame neck. there is a loop the cables go through under the neck cover. There is also a "spring" around the cables. either of those could rattle at RPM and make a noise.

And last but not least.....connectors in the headlight bucket rattling. This one took a while to find.
 
#16 ·
that's far louder than mine, but mine has been intermittently getting louder and changing pitch for years. did you do the earshave? I have to wonder if (ruling out all other loose parts, of course) it might just be the sound of the valvetrain through the pod filters I have... in your case though, that seems less likely. Mine is more of a tap with a ring, yours has a very definitive tone to it
 
#18 ·
Half of it was the gas cap lock. I took it apart and put an o-ring between two of the mechanism sections and it solved that.
There is still noise coming from the front end somewhere that I can't isolate.
 
#22 ·
Good to hear you got yours solved.

I found out yesterday what the noise was on my bike. I randomly decided to release my handlebar and what do you know. The bolt sitting right on top of the upper steering stem (don't know if that's the right word?) under the handlebar mount was unscrewed like an inch! The washer sitting underneath it was the ratteling s.o.b. Tightened it all down and the worst noise is now gone. There still is something else making a lower, quieter ratteling sound but it doesn't bother me as much.

Here's a short vid to show what I'm talking about

youtube.com/watch?v=hV3eC1vRWiA
 
#23 ·
If it occours at a specific engine speed (whether moving or not) it's a harmonic vibration. Could be a lot of different things. Heatsheilds, cables, licence plate, and even something loose in the gauges or headlight bucket.
I have a weird "buzz" on my bike that I've found to be caused by the windscreen at a certain RPM. Honestly I just wear earplugs and don't worry about it. If it's always at 5,000 rpms, seems like you got a nifty shift indicator;)
 
#24 ·
I found and fixed mine. Might be worth looking at. My front gas tank bolts/washers vibrate on the tank tabs, I could press or pull on the tank while riding and it would go away. I added a big washer under it to keep it tight and it's gone! Now I can hear the other side starting to do it, one more washer and I should have it!!
 
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#26 ·
Finally found it. A broken fan motor bracket. Welded it and Noise greatly went down!
Still sounds like there is another loose smaller washer. I'll try pulling the handlebars like the one person suggested.
 

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#27 ·
After welding the broken bracket, the other two legs of the fan motor bracket broke and made an even worse noise! Rather than fixing it I replaced it with a good used one.

After fixing that, I got another metallic ringing noise. The forward cylinder head coolant pipe bracket broke. Lucky it didn't pop out of the head! Welded it and bent a washer to actively retain the tube in case the weld/bracket breaks again.
 
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#29 ·
Glad you found the cause of the noise. I would not try to rebuild the oem tensioners. It cannot be done. If the tensioners are bad, then the threads on the plunger and inside the aluminum tensioner body are also worn out. Either get the TOC manual tensioners, or get new oem tensioners, which you can expect to last 10-12,000 miles before they are worn out and need to be replaced again. Trying to rebuild worn out tensioners is risking destroying your engine. I have compared the internal threads between a new oem tensioner and a worn out tensioner, just out of curiosity. The threads on the worn out tensioner showed considerable wear compared to the new one Installing stronger springs will not do any good. I'm surprised the still sell those things.
 
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