V11 Sport with strange metallic rattle

[Chuck]

As can be seen with the K line video, it's not rocket science. Just good standard machine shop practice, and no special tools, other than the rivet hammer, which is readily available cheaply.

[shiloh]

A lot of discussion here, could the noise/ rattle be piston slap, im well versed in that sense running hp 2 strokes, it can be present at idle and increase with speed and load. Sloppy pistons can be noisey. (Detonation sounds like a can full of steel balls, and usually caused by a lean condition at high rpms)

Just a thought, maybe check rings and piston clearances, small end cages, pins etc.

[Tinus89]

Good thinking. However, there was no damage to the cilinders that indicates slappy pistons, and the pistons including their coating on the "wings" were really in good shape.

Any small end play I would expect to cause a continuous tapping sound instead of irregular?

[Tinus89]

So, while I continue to ride her, the rattling noise still increases... and keeps me worried.

After a good long ride, I made another (hopefully clearer) set of videos:

 

Here a video of it idling:

https://www.youtube.com/watch?v=4chn9SpxJQM

 

And here a video of me revving her a little:

https://www.youtube.com/watch?v=E9y8YuI5X0I

 

Any new ideas?

[Chuck]

 Sounds normal to me. Of course, I always wear ear plugs and don't generally hear the cacophony of sounds a Guzzi makes.. but.. I didn't hear anything in the video. 

[coreytrevor]

Wow, that doesn't sound good to me, though it's hard to tell from a recording like that.

 

I hear a lot of kind of random tappy rattling that makes me think of something in the valvetrain, but is there also a lower frequency heavier thump kind of sound? I heard something heavier toward the end of the second video when the revs were dropping from about 2500 to 2000rpm, but it might just be an anomaly from the recording.

 

I read through the thread but didn't see any mention of whether the sound changes with the amount of load placed on the engine, while riding. If you are riding and playing with the throttle, does the sound change with varying throttle? 

[JBBenson]

OK, throwing this out there:

 

One or more of the lifters are snapped in two, and the ends are clicking and clacking together as the cam actuates it/them.

 

It sounds bad. I wouldn't drive it until I figured it out.

[czakky]

I'm mostly with Chuck. Do you have good tension on your wave washers at the tappers?

Are your plugs coated in oil?

[docc]

How many km have you ridden it like this? Are all of the valves holding their adjustment?

[Tinus89]

I hear a lot of kind of random tappy rattling that makes me think of something in the valvetrain, but is there also a lower frequency heavier thump kind of sound? I heard something heavier toward the end of the second video when the revs were dropping from about 2500 to 2000rpm, but it might just be an anomaly from the recording.

 

I read through the thread but didn't see any mention of whether the sound changes with the amount of load placed on the engine, while riding. If you are riding and playing with the throttle, does the sound change with varying throttle? 

 

It does vary with throttle, as you can hear in the second video as well, frequency increases with revs and slowly dissipates at higher revs.

I don't hear any heavier thump kind of sound though...

 

One or more of the lifters are snapped in two, and the ends are clicking and clacking together as the cam actuates it/them.

 

Lifters like in tappets? Because cam, tappets, rockers etc. are in good condition.

 

I'm mostly with Chuck. Do you have good tension on your wave washers at the tappers?

Are your plugs coated in oil?

 

I think I do, but is there any way to confirm? Should I maybe run her without valve covers for a min or two to inspect?

Plugs are fine, not coated in oil. Also the exhaust port is clean, she does not smoke. I can take them out and take a picture of them tomorrow? That would be straight after shooting this video...

 

How many km have you ridden it like this? Are all of the valves holding their adjustment?

 

I'd say since the sound stated to originate (start of this topic) ~2500km? However the last 500km it has gotten significantly worse.

Valves are holding their adjustment quite good.

[docc]

I cannot remember if you have inspected the timing chain and tensioner?

[Tinus89]

I cannot remember if you have inspected the timing chain and tensioner?

 

I replaced the original chain+tensioner, but the sound stayed. Later, I also took apart the entire engine, inspected everything, had a specialist shop repair and rebalance the crankshaft, replaced the big end shells, one crankshaft bearing (timing side) because of too much wear etc. After re-assembly, the sound was still there. The only part I did not take apart was the heads....

[coreytrevor]

It does vary with throttle, as you can hear in the second video as well, frequency increases with revs and slowly dissipates at higher revs.

 

 

Yes, but what I meant was when there is a load on the engine while riding, does the sound change depending on how much or little throttle is applied. The idea is to change throttle position, keeping rpm steady. It's easier in higher gears because playing with the throttle won't change the rpm as quickly, or you can drag the rear brake a bit. You can't really do this in neutral very well.

 

If the sound changes with varying amounts of load on the engine, it tends to indicate the noise is piston/wristpin/big end/mains etc. Something from the piston down. Usually valvetrain and timing chain noises can change with rpm but not just from varying throttle position while rpm stays the same. 

 

Did that make any sense?

 

 

[Chuck]

A rattle when you let off throttle is generally rod bearings. A main bearing normally is a low pitched thump, especially at startup before oil pressure builds. How fast oil pressure bleeds off after shutdown is a good indication of bearing condition, but it (naturally) requires an oil pressure gauge.

I'm not hearing any of those sounds in the video. Possibly you are hearing the rocker arms going from side to side? There is a mod to put a thrust bearing on the rocker arm shaft to stop that.

I'm still having a problem being concerned about what I'm hearing. Maybe I need better hearing aids? 

FWIW, I chased a noise in a Strada for months. Tore it down twice, balanced the entire rotating assembly. Eventually found it was a crash bar doing it. 

[Tinus89]

 

It does vary with throttle, as you can hear in the second video as well, frequency increases with revs and slowly dissipates at higher revs.

 

 

Yes, but what I meant was when there is a load on the engine while riding, does the sound change depending on how much or little throttle is applied. The idea is to change throttle position, keeping rpm steady. It's easier in higher gears because playing with the throttle won't change the rpm as quickly, or you can drag the rear brake a bit. You can't really do this in neutral very well.

 

If the sound changes with varying amounts of load on the engine, it tends to indicate the noise is piston/wristpin/big end/mains etc. Something from the piston down. Usually valvetrain and timing chain noises can change with rpm but not just from varying throttle position while rpm stays the same. 

 

Did that make any sense?

 

 

 

 

Makes perfect sense. However, as you can hear on the "revving" video, the sound is hard to hear at 2000rpm and impossible at 3000. Well, I don't know if you can roll along under load on your V11 at 2000rpm, but I can't without creating all kinds of other noises (rattles on the bike, in the drivetrain etc).

 

A rattle when you let off throttle is generally rod bearings. A main bearing normally is a low pitched thump, especially at startup before oil pressure builds. How fast oil pressure bleeds off after shutdown is a good indication of bearing condition, but it (naturally) requires an oil pressure gauge.

I'm not hearing any of those sounds in the video. Possibly you are hearing the rocker arms going from side to side? There is a mod to put a thrust bearing on the rocker arm shaft to stop that.

I'm still having a problem being concerned about what I'm hearing. Maybe I need better hearing aids? 

FWIW, I chased a noise in a Strada for months. Tore it down twice, balanced the entire rotating assembly. Eventually found it was a crash bar doing it. 

 

It does not rattle more when I close the throttle.

Before replacing the main bearing, the oil pressure was measured with a semi-warm engine: 4,5bar straight after tickover. After that I even replaced the main bearing, causing it only to get better...

I'm not worried about oil pressure issues at all. The only things I can really think of are still an issue with the timing chain/tensioner (is that possible when new?), but for me it sounds too loud and metallic for that.

Therefore... valve train.

 

The rocker arms moving side to side is of course something I can check relatively easily (run her with the valve covers off).

Some questions:

 

- Should the rocker arms even come off the "lower" side (against the spring) or stay firmly into place?

- Could a worn valve stem cause a sound like this?

- Could a loose valve seat cause a sound like this?