@marius_ Clutch plates slipping and/or noise? Notice any slippage?

What type of engine oil is being used?

 

No slipping observed. I had slipping with the 696 so I can tell Also there’s enough leeway on the clutch lever.

Oil used for refill is Motul 7100 15W-50, per the previous owner‘s service bill it’s the same that was put in by Ducati in Munich.

 

Has it been drained and replaced? Or just topped off?

 

Just topped off, oil change is set for July 22nd.

The Ducati workshop (one of the bigger ones, in Munich) put in the 7100, honestly I doubt it's the cause. I'm curious what they'll say. I found that they offer covid-19 consulting via whatsapp, so I sent them the audio file as well

I hear the belts running on the pullies. My bike just started doing it when I got the belts changed for the 18k service.

Perhaps that's not the sound you were referring?

Did you have a similar sound? It's really loud and obvious; were it a car it'd immediately say "belt slipping". Only that the noise stops entirely when I pull the clutch (at least as much so that I can't hear it anymore), is a bit strange to me. And on acceleration there is no (audible) noise, but again perhaps then it's covered by the engine noise.

 

And if you do drain the existing engine oil, and replace it with new oil and filter, you might try the Shell syn instead of Motul. Motul syn should be fine, but just to eliminate some possibilities. Also, of course, inspect the drained oil for peculiarities that might be found.

 

I hear the belts running on the pullies. My bike just started doing it when I got the belts changed for the 18k service.

Perhaps that's not the sound you were referring?

 

That's a weird sound, like a belt squaling but I'd expect the pitche to rise and fall twith the engine speed, but it doesn't. It does get louder and softer with engine speed though which makes me think it's vibration related. Is it speed related? Can you replicate the noise while the bike is in Neutral on the sidestand?

Do you have a stethoscope, even one that's a childs toy? Or a piece of silicon tubing to try to pinpoint the noise?

 

That's a weird sound, like a belt squaling but I'd expect the pitche to rise and fall twith the engine speed, but it doesn't. It does get louder and softer with engine speed though which makes me think it's vibration related. Is it speed related? Can you replicate the noise while the bike is in Neutral on the sidestand?

Do you have a stethoscope, even one that's a childs toy? Or a piece of silicon tubing to try to pinpoint the noise?

It’s not speed related but often it stops when the bike stops moving. Not always though and today it was even while waiting at the traffic light. It appears in neutral also; this was when I walked around the bike to hear where it’s loudest. I don’t have a stethoscope of any kind but it’s a good idea.

What if this is the flap mechanism in the exhaust? Opening/closing... the sound it makes corresponds with the engine. It's my thought and I'd try it for once.

I did „maintenance“ on the flap mechanism a few weeks ago by spraying it with liquid grease (it solidifies after it has dried, it’s used for belts and chains on machines). I thought it’s best to keep water and grime out. I had the engine light on and read out the exhaust valve failure. After the spraying/cleaning action and deletion of the error the light didn’t come back on. I could try demating the connector.

 

What if this is the flap mechanism in the exhaust? Opening/closing... the sound it makes corresponds with the engine. It's my thought and I'd try it for once.

 

"When I pull the clutch it goes away."

 

Good quote, actually that’s during driving. Now that I’m trained to hearing the noise I think it’s always there but just not audible when using throttle. Could it be that some level of exhaust gas is needed, thus pulling the clutch let’s the engine calm down to a low-enough pressure so that it almost goes away?
But then again the one time I stopped and walked around the bike I didn’t use the throttle.

Also one more hint, as far as I can tell it only happens when the engine (or exhaust?) is warmed up.

 

But yes to be precise once more, the noise diminishes a lot when I pull the clutch.

 

Hmm, listening a second time, it seems to happen more on deceleration, or when the motor is not loaded...

 

Throw-out bearing?

 

I really hope it’s not some central bearing, like thrust main shaft or how that’s called. Sounds expensive, also time-wise.

 

Addon: I totally missed and forgot, but some time ago when I opened the exhaust valve cover to lube the valve and get rid of the check-engine light, I found a loose nut inside the exhaust valve cover. It's one like spare part no. 74940081A. I found it in the spare parts catalogue as one that's on the tension roller on the timing belts. So I removed the fairing and belt covers and everything looked ok, also the tension was as expected and nothing strange at all (just to also exclude the belt system, unless it's a bearing issue somewhere).

The nut is not one of those which fix the exhaust pipe flanges; those nuts are smaller. I thought for a moment that some exhaust gas might blow by if one of the nuts is gone and the seal wouldn't seal anymore.

I found the attached pic of an exhaust valve (believe it's from a Diavel), and the top nut also doesn't look like the one I found. But I don't know where it then should come from... Unfortunately, one of the brand new screws for the exhaust valve cover which I tightened with correct torque plus anti-seize paste, is locked again and I manages to round the head again... Need to drill it out once more to gain access to the exhaust valve... But if the nut I found is the top nut of the exhaust valve itself, it might be causing the noise. Another data point, when switching on the ignition I can hear the exhaust valve move once as usual, sounds ok and normal...

Any other ideas concerning the nut and/or noise? Ducati hasn't listened to my audio file sent via whatsapp yet... I'll ask what's up. On July 22nd I've got the annual inspection.

 

@marius_ Seems unlikely the top nut of the exhaust valve might be causing the noise…

 

Checked today for peace of mind, yes it's all alright down there. But the nut I found is weird, perhaps it's not from my bike at all


sorry for editing once more, just be sure to read the post prior to this one on page 1 which has the new findings of today

 

Hi all,

I have some new observations:

- the noise appears with and without clutch engaged. When I disengage the clutch, the engine revs are low and thus the noise is appearing "less frequent" (but same audio frequency), so it's tied to RPMs but only for occurence and not for pitch. If you know what I mean.

- the noise is audible while still standing in neutral. I went around the bike and it's loudest when you put your ear next to the ignition/key or steering stem nut. So it appears to come from the front of the bike below the tank, probably the airbox. Which makes me think that the air filter and/or inlets might have caught something that moves when air is pulled or it lost its proper seat and there is some "blow-by" of some sort. Or somewhere else something is wrong in the airway, but not in the gearbox or timing belts. More air is pulled when RPMs are higher, disengaging the clutch will cause less air to be pulled, so that makes sense if the noise slowly disappears.

I'll change the title of the thread for the clutch misinformation. I'll search for some air filter disassembly hints (I know they're in this forum somewhere; edit: here) and then see if I find time before the annual service on Thursday to check the whole area below the fuel tank.

 

Ah, could be that some debris acts as sort of a 'trumpet' with the air flowing around. Don't give up! : )

 

Air filter is clean... might be the water cooling system... The noise appears when the engine is warmed up. I just need to pull the throttle in neutral on the parking lot. Any other ideas what I could check before going to the dealer on Thursday?

 

I think you could just get rid of the fairings - once it saves time at the dealer - later you can put them on "for free", second you are not limited with them to hear and use the "spoon" or screw stetoscope? It's still couple of days till Thursday... Airbox... but if it would get unwanted air for example the engine would not work smooth, you know, the mixuture is not ideal to be burn - I doubt computer can correct it. This "trumpet" 🎺 sound is not fitting to a big thing... it's too high. Could it be some of this hoses for pressure in the tank or hm... ok, clearly I'm out of ideas now.

 

cooling liquid seems alright in terms of quantity. water pump pressure blowing off? it sounds like some overpressure valve that blows, but the noise appears "all the time" which then would be weird can't be constantly blowing off something for the last 700 km.

 

Ducati wrote back on Whatsapp, say they need to have a look at it. No hint as to what else I could check, though.

 

edit: the below didn’t fix it. Read on in post #30.

Ducati listened to the noise this morning and said it's the timing belts, which have too much tension. So when hot, they make this noise. It's unusual they said, for the age of my bike and the km it has been ridden. Anyway they gave me a Diavel 1260 as replacement for today because for the correct tensioning the engine needs to be cool, obviously. I'll pick it up tonight and hope it's solved.

 

I bought the bike at a KTM dealer, perhaps they put too much tension on them during inspection before selling it...

 

@marius_ Wow, very interesting…

 

I picked up the bike but the noise is still there. They adjusted the timing belts but it wasn’t the root cause. Something is weird in the airbox, there are apparently some flap/oneway valves and hoses which can cause the issue. Ducati will need 5 hrs to take it all apart and investigate. Since my bike has seen the service regularly, Ducati may share the labour cost with me 50:50. It’s out of warranty so it depends a bit. If they find something really wrong then they may also pay it all.

At least it’s nothing crucial and I could choose to leave it as is, technically. But I can tell you that’s no option as the noise is very annoying for me. I may open the airbox myself once more or think about making the 5 hr appointment, earliest August 20.

 

FWIW, my bike made a similar noise but under different circumstances. The sound was very similar to yours, but a constant high pitched sound. I noticed it when I turned off my bike after a ride. It turned out to the one of the vent hoses for the gas tank that apparently had been compressed when I was reseated my tank after doing some work. I'm not sure which one it was, I just lifted the tank again and made sure the hoses were cleanly sorted and there was no gathering under he tank and the sound went away. Believe someone else on the forum had a similar problem. Probably not the same as you but easy to check out.

 

Yes, I'll lift/remove the fuel tank and check myself what's up. In the spare parts catalogue drawings I haven't found any rubber flapper valves Ducati mentioned, but there are some ventilation hoses and valves (crankcase ventilation, fuel tank ventilation etc.). I might have to remove the tank, so I'll be looking for instructions if available. The new air filter arrived, and I'll exchange it as well in the process anyway, so it's a win-win to open up the fairings again and all that

I hope I'll be able to leave the fuel lines connected so I could run the engine with the tank lifted up. Then I could touch all hoses and see if one of them causes the noise.

 

I had it all opened up today but I can’t really find the root cause. It’s not louder when the airbox is open. I’m still thinking it might be some bearing somewhere in the front of the bike. I guess I’ll have to get it back to Ducati and let them take it all apart.