Howling noise at 75-80 mph (not wind) '09 ABS with 39k miles running synthetic

[Rubber_Snake]

I searched around, and though I found some discussions related to the clutch and final drive, I haven't found any discussion related to this particular situation.

So, regardless of gear (I've checked 4, 5 & 6), when my Connie is at 75-80 mph, there is a loud howling noise that seems to be coming from the engine/transmission area.  If I back off or speed up over that range, the noise goes away.  While it's howling, if I pull in the clutch lever, it instantly goes away.  This is why was hoping it could be related to the clutch and not the final drive.  Considering that the final drive is always spinning at the same rpms at 75-80 mph and the clutch isn't because I've tested this in different gears, I'm thinking that it might be the in the FD. Otherwise, the bike runs flawlessly. 

Has anyone ever experienced this?

Thanks guys,

Ray

[B.D.F.]

Right off the bat, let me say that I have never experienced this nor do I even have any reasonable (meaning logical, thoughtful) guesses. That said.....

You are correct in that the entire final drive, the bevel gears and 1/2 of the clutch all spin with the rear wheel. The rest of the clutch and the entire engine and transmission do not. Unfortunately, often a gear while will only sound under load so it may well be the final drive and the reason it quiets down when you pull in the clutch is because all load is removed from it, not because ti stopped turning. Running gears that are badly worn often show a line or ridge, and that is the cause of the noise but again, only under load.

The only thing that may be useful that I can think of to suggest would be to either have someone else ride with you, move around and perhaps lean over each side fo the bike enough to try and find the side of the noise source. Another thing might be an inexpensive mechanic's stethoscope with the probe removed so only the hose is left; pointing the end of the hose around should home in on the source of the noise pretty accurately.

Of course I realize this must all be done at highway speeds and so do so safely, perhaps including strapping the passenger to yourself while riding so nothing terrible can happen.

Last idea is to run the bike on a dynomometer. Unfortunately almost all of them in existence are DynoJet dynos, and they are not 'real' dynos capable of putting a load on the bike at a steady speed. Still, a DynoJet dyno would allow you to repeatedly power the bike up through that speed range while others stood and listened for the noise; it should not take very many cycles to find it as you describe it as a howl.

Best of luck with this....

Brian

I searched around, and though I found some discussions related to the clutch and final drive, I haven't found any discussion related to this particular situation.

So, regardless of gear (I've checked 4, 5 & 6), when my Connie is at 75-80 mph, there is a loud howling noise that seems to be coming from the engine/transmission area.  If I back off or speed up over that range, the noise goes away.  While it's howling, if I pull in the clutch lever, it instantly goes away.  This is why was hoping it could be related to the clutch and not the final drive.  Considering that the final drive is always spinning at the same rpms at 75-80 mph and the clutch isn't because I've tested this in different gears, I'm thinking that it might be the in the FD. Otherwise, the bike runs flawlessly. 

Has anyone ever experienced this?

Thanks guys,

Ray

[maxtog]

Like Brian, I have never heard of this issue before.  You didn't say WHICH oil....  if it is related to the clutch (and I am not saying it is), keep in mind that generally you should use a motorcycle grade oil (synthetic or not) because it has the right amount of additives for wet clutches.

You should add the model year to your signature and/or avatar (and minimally each post), and also indicating how many miles on the bike would also be useful for those trying to help you.

[Rubber_Snake]

Like Brian, I have never heard of this issue before.  You didn't say WHICH oil....  if it is related to the clutch (and I am not saying it is), keep in mind that generally you should use a motorcycle grade oil (synthetic or not) because it has the right amount of additives for wet clutches.

You should add the model year to your signature and/or avatar (and minimally each post), and also indicating how many miles on the bike would also be useful for those trying to help you.

Duly noted, sir.  AMSoil Synthetic 10W-40, I do not know what type of gear oil is being used right now.  I bought it from a friend.  I'll check with him. 

Thank you.

[Rubber_Snake]

Duly noted, sir.  AMSoil Synthetic 10W-40, I do not know what type of gear oil is being used right now.  I bought it from a friend.  I'll check with him. 

Thank you.

Running AMSOIL 10W-40 engine and 75W-90 gear since new.

[maxtog]

Running AMSOIL 10W-40 engine and 75W-90 gear since new.

Kewl.  Note that Amsoil makes both motorcycle and non-motorcycle oils.  This is the motorcycle one:  http://www.amsoil.com/shop/by-product/motor-oil/motorcycle/10w-40-synthetic-metric-motorcycle-oil

Smooth, Confident Shifts: AMSOIL Synthetic Metric Motorcycle Oil contains no friction modifiers and promotes smooth shifting and positive clutch engagement. It is engineered to control heat and prevent slippage and glazing, promoting longer clutch life.

I am not sure just how much real-world difference there is between motorcycle and non-motorcycle oils, but I have always used the latter.

[smokin]

Interesting noise,possibly  output gear related noise if it goes when the clutch is pulled in.

[B.D.F.]

The only issue regarding wet clutches and the oil used with them that I know of is oils containing some very specific, extreme pressure additives. These oils are rare, if available to road use consumers at all. Some oil additives do contain them.

Many motorcycles with wet clutches use and have been using automotive oils for years with both excellent success but more importantly, no clutch problems.

And the problem they cause is slippage between the plates but nothing that would generate noise.

I do not believe the oil used in this motorcycle can or has caused any clutch damage that could result in his stated problem. While he may not yet know what the problem is, I would not look toward an oil- damaged clutch anytime early int the diagnostic cycle. Besides that, it is very easy to tell if a clutch is slipping; put the bike in a fairly high gear, say, 4th or higher and stab the throttle while watching the spedo and tach. If they 'split', meaning the tach. suddenly runs away from the speed at which the speedo is climbing, the clutch is slipping. Otherwise, all is well regarding clutch slippage. But again, I do not think this is a worthwhile place to look.

My purpose here is not really about oil, it is about trying to steer this poster toward his problem as quickly and efficiently as possible.

Brian

Like Brian, I have never heard of this issue before.  You didn't say WHICH oil....  if it is related to the clutch (and I am not saying it is), keep in mind that generally you should use a motorcycle grade oil (synthetic or not) because it has the right amount of additives for wet clutches.

You should add the model year to your signature and/or avatar (and minimally each post), and also indicating how many miles on the bike would also be useful for those trying to help you.

[maxtog]

I do not believe the oil used in this motorcycle can or has caused any clutch damage that could result in his stated problem. [...]My purpose here is not really about oil, it is about trying to steer this poster toward his problem as quickly and efficiently as possible.

Agreed.  I seriously doubt it is the oil, just addressing that part of the subject with no intent of trying to steer it into YAOT (yet another oil thread).

[smokin]

Does the noise go away when on over run at the speed you refer to? If  it reoccurs when throttle is applied then I would suggest diff period noise.I.E., crown wheel to pinion mating noise.

[Rubber_Snake]

Does the noise go away when on over run at the speed you refer to? If  it reoccurs when throttle is applied then I would suggest diff period noise.I.E., crown wheel to pinion mating noise.

Hey Smokin',

I'm not sure what you're asking, but generally I hear the howl when either slowly accelerating through that speed range (75-80) or just maintaining a speed there.  As soon as I go past or drop below, it goes away.  I haven't tried accelerating hard through the speed range, if that's what you're asking.  (Or, to be more specific, paid attention to the noise when hard on the throttle). If so, I'll give it a try and report back. 

P.S. I use the AMSOIL Metric synth.

Ray

[Conrad]

Brian,

No howling but didn't your bike whistle? 

[B.D.F.]

Yes, that was me and my bike. Annoying but not harmful; it was up around the fairing / windshield area. Never found it either although it did quiet down somewhat.

It annoyed me enough that I was covering 1/2 of the front of the bike with Hefty garbage bags at a time in an effort to find it and still I could not locate that damn thing.

Brian

Brian,

No howling but didn't your bike whistle?

[Diablo6v]

I'm leaning towards dive shaft and or bevel gear..Pop the drive shaft out and take a look.

[Conrad]

Yes, that was me and my bike. Annoying but not harmful; it was up around the fairing / windshield area. Never found it either although it did quiet down somewhat.

It annoyed me enough that I was covering 1/2 of the front of the bike with Hefty garbage bags at a time in an effort to find it and still I could not locate that damn thing.

Brian

When I wash my bike I use my leaf blower to get the water out of the nooks and crannies. While doing this I discovered a whistling sound coming from the hollow front axle when the blower hits it just so. Maybe that's where your whistle comes from? 

[VirginiaJim]

Was a bird nesting in it?

[B.D.F.]

IME, they tend to go for the slower, easier- to- catch bikes like the ones with floorboards.....

Grinnin', Duckin' and Runnin'

Brian

Was a bird nesting in it?

[B.D.F.]

Interesting idea! It could be the source, what was really odd about it was that I could not locate it or even get a sense of where it was coming from. If it was the axle, then the noise would probably come up in front of the tank and bounce all around the fairing, so that would explain the lack of a single source of the noise.

Oh well, at least it must have been a treat for others to watch me ride down the road with a black Hefty bag draped over 1/2 of the front end of the bike; at least it took a little heat of Mr. Elkhoof probably 'cause it is hard to notice the 2" crevice in the bottom of the Grand Canyon.

Brian

When I wash my bike I use my leaf blower to get the water out of the nooks and crannies. While doing this I discovered a whistling sound coming from the hollow front axle when the blower hits it just so. Maybe that's where your whistle comes from?

[VirginiaJim]

IME, they tend to go for the slower, easier- to- catch bikes like the ones with floorboards.....

Grinnin', Duckin' and Runnin'

Brian

 

[smokin]

Hey Smokin',

I'm not sure what you're asking, but generally I hear the howl when either slowly accelerating through that speed range (75-80) or just maintaining a speed there.  As soon as I go past or drop below, it goes away.  I haven't tried accelerating hard through the speed range, if that's what you're asking.  (Or, to be more specific, paid attention to the noise when hard on the throttle). If so, I'll give it a try and report back. 

P.S. I use the AMSOIL Metric synth.

Ray

Ray it doesn't sound like gear or bearing noise from your above information,usually bearing or gear noise tends to be constant,especially bearing noise.Diff gear noise can be a period type noise at certain speeds which can be driven through occurs either on throttle or over run.
I would check tyres for defects,do you have a rear wheel hugger?,it so make sure it is not rubbing in any spot as the tyre distorts at speed.
As for an oil problem,no I doubt it.
I also use Amsoil 10w40 synthetic oil and their 75w90 diff oil since 3000kms,now covered 15500 km with no concerns.