Name that engine sound: E5 V85TT edition

[Midnite]

After two years, and just a touch over 10,000 miles, I still love my V85TT, though it's certainly given me some grief along with many miles of smiles. It's pinged in heat a number of times, occasionally with an accompanying flashing CEL, has suffered from a chattering clutch in the heat when accelerating from a stop, and the cruise up/down toggle no longer works when cruise is engaged. I've also adjusted valve lash back to a spec three times, the last two times at about 3k and 8k miles following overheating/pinging events. I had high hopes that all of these were teething issues, and that the old girl would settle into her stride around 10k miles, but...

About a month ago, just before my factory warranty was set to expire, I started noticing that my engine began knocking after cold start; knocking begins about 10 seconds after firing up, can last for up to a minute, then goes away. Once up to temp, she seems fine, and it doesn't knock if I stop for a while and fire her back up. It only occurs after a cold start. I'm wondering if this is indicative of premature wear of engine components due to overheating (piston slap?) or something else. I adjusted valves just 2,000 miles ago (on the compression stroke, verified by rolling engine over three times), and just changed the oil a few days ago to see if this would help (it didn't).

Any ideas what this knocking behavior may indicate? Premature wear of engine components? Should I avoid riding the bike for now? I have unsuccessfully tried to engage my dealer and Piaggio resolving all of the issues mentioned, including the recent knocking development, but haven't gotten anywhere yet (much more to this story). Curious as to what the mechanical experts among you think this new knocking sound may be.

Happy New Year!

This past summer, in her natural environment: CA hwy 36 between Red Bluff and Fortuna...

 

[Vagrant]

What year? Is it burning oil?

 

[Midnite]

It's a 2021, Vagrant. Has been using some oil, but nothing too far out of the ordinary (went from just over halfway in the sight glass to the low mark after a 1200 mile journey this summer, including some extended stretches on highways/freeways in 90 degree+ weather).

Just wondering what seasoned mechanics like yourself think this may be, Scott, based on the video example I provided. Not looking for a definitive diagnosis. I tried going the dealer/Piaggio route earlier this year. My bike sat there for nearly two months before the dealer got back to me and told me that Piaggio declined to tear the bike down to investigate. I'm still trying to get them to take action.

In the meantime, I thought I'd see what the GT community thinks and recommends.

Thank you for your comments.

 

[scottmastrocinque]

Apologies, but I did not see your hyperlinked video until just now.

Still, the sound quality is so poor it is impossible to distinguish.

My suggestion is go to your nearest Harbor Freight Tools.

373 S McDowell Blvd #10b, Petaluma, CA 94954

Buy this:







Utilize it to listen to your engine. Work your way from the top of the valve cover, downward, until you identify the precise location of the origin of the sound.

The sound appears very rhythmic and sounds like excessive valve lash to me but again, I am guessing in the dark.

If you report back where you locate the sound to be, we should be able to help you better.

 

[Vagrant]

If you’re sure oil check was under identical circumstances then that’s about what mine with bad rings was using. I’d assumed the 21 was fixed but maybe not. I’d ask for a leak down test before warranty is done.

 

[Midnite]

Scott: Thanks so much for your thoughts and advice: very much appreciated!
When I listen to the video on my laptop (or on my phone with earbuds), I clearly hear the knocking appear around the 20 second mark, and it seems distinct from valve clatter. Do you hear this? It becomes much less distinct around the 1 minute mark.

I'll pick up a mechanic's stethoscope, and will try to pinpoint the sound's location. Part of what I reported to my dealer/Piaggio while my bike was there for inspection (late September to late July of 2023) was that valve lash loosened every time I checked it: at break in, again at around 3000 miles and again at 8100, when I set them last. I haven't experienced this rate of change in any of the previous Guzzis I've owned (including two other small blocks). I also haven't experienced the overheating/pinging/pre-detonation on any of my other Guzzis. Now, with just over 10k miles, and a few California cold starts (in the mid 40's F), valve clatter has increased, and now this knocking sound has appeared. Even though I set valves a mere 2000 miles ago (which noticeably quieted the valve train and improved performance), I'm now tempted to go back in and check again. The fact that valves are so quickly going out of spec seems to indicate a larger problem to me. Piaggio's response was that they suspected that I didn't set valve lash correctly, and so, they declined to proceed with the investigation (this, two full months after I brought the bike in). I attempted to follow up via my dealer, but the dealer was unresponsive in the extreme.

Thanks for your thoughts, Vagrant. I'm wondering if the rings have started to go on mine, or if there's some other mechanical wear to the piston/cylinder causing this knock. My warranty expired on 12/31/23. I fired off an email to Piaggio North America a few days beforehand, frustrated that my dealer hadn't been responding, reiterating the issues that I had raised during the active warranty period, and expressing concern about the new knocking sound that has appeared. I await their response...

Will report back with more information as I have it. Thanks again.

 

[scottmastrocinque]

Scott: Thanks so much for your thoughts and advice: very much appreciated!
When I listen to the video on my laptop (or on my phone with earbuds), I clearly hear the knocking appear around the 20 second mark, and it seems distinct from valve clatter. Do you hear this? It becomes much less distinct around the 1 minute mark.

I'll pick up a mechanic's stethoscope, and will try to pinpoint the sound's location. Part of what I reported to my dealer/Piaggio while my bike was there for inspection (late September to late July of 2023) was that valve lash loosened every time I checked it: at break in, again at around 3000 miles and again at 8100, when I set them last. I haven't experienced this rate of change in any of the previous Guzzis I've owned (including two other small blocks). I also haven't experienced the overheating/pinging/pre-detonation on any of my other Guzzis. Now, with just over 10k miles, and a few California cold starts (in the mid 40's F), valve clatter has increased, and now this knocking sound has appeared. Even though I set valves a mere 2000 miles ago (which noticeably quieted the valve train and improved performance), I'm now tempted to go back in and check again. The fact that valves are so quickly going out of spec seems to indicate a larger problem to me. Piaggio's response was that they suspected that I didn't set valve lash correctly, and so, they declined to proceed with the investigation (this, two full months after I brought the bike in). I attempted to follow up via my dealer, but the dealer was unresponsive in the extreme.

Thanks for your thoughts, Vagrant. I'm wondering if the rings have started to go on mine, or if there's some other mechanical wear to the piston/cylinder causing this knock. My warranty expired on 12/31/23. I fired off an email to Piaggio North America a few days beforehand, frustrated that my dealer hadn't been responding, reiterating the issues that I had raised during the active warranty period, and expressing concern about the new knocking sound that has appeared. I await their response...

Will report back with more information as I have it. Thanks again.

Hello,

I went into my shop and blasted the video through my speakers there. I can hear the ticking getting louder at the 20 sec mark like you say.

Again, to my ear, it sounds like excessive valve lash. I am virtually certain that with the mechanic's stethoscope, you will hear the sound loudest immediately above the rocker arm above the valve stem.

Please do not take offense as I am asking because I do not know you or your skills.

You say that you adjusted your valves. Are you skilled at this and do you know 100% what you are doing when you perform this? I ask because I have seen 1000x a motorcycle that was serviced by the owner who claimed that they knew how to do a valve adjustment, but in fact, they had screwed it up badly.

If you are very experienced with valve adjustments, then my next thing I would look at is the removal of the cylinder head and complete examination of the components within. Maybe your valve seat is giving way and the gap keeps increasing as damage continues.

I do not believe it is a rings issue. Too rhythmic for rings to my ear and to centralized to my ear from its point of origin.

You did not say how much your value clearance changed from inspection to inspection, and this would be a great piece of information.

 

[Midnite]

Thanks again, Scott. No offense taken. Glad to hear that you don't think the rings are going south. I am by no means and experienced mechanic, but do have a fair amount of experience completing valve adjustments on small block Guzzis specifically. I had a 2016 V7ii that I successfully adjusted valves on through 20k miles when I sold it (every 5k miles), and currently have a 2022 V7 850 with 5000 miles in addition to the V85TT. I rotate the rear wheel until I'm on the compression stroke as Todd demonstrates here, rotate up to TDC (using a plastic straw), and check for movement at the rocker arms before setting lash. The last time I set lash on my V85TT, I rotated the engine to TDC on compression stroke 2 additional times to verify lash. I'm not comfortable tearing down the engine myself, so am still trying to get Piaggio to follow up and take this on.

Here are my valve lash measurements thus far:

900 miles: LEFT .1 I / .18 E RIGHT .15 I / .17 E
3328 miles: LEFT .12 I / .2 RIGHT .12 I / .18 E
8147 miles: LEFT .2 I / .23 E RIGHT .15 I / .23 E

I inspected and adjusted at 3328 and 8147 after instances of pinging under load while hot, and seeming deterioration in responsiveness and engine performance. Valves were adjusted to factory spec each time: .1 Inlet / .15 Exhaust.

 

[Midnite]

Quick update, and some more information: When I had a chance, I checked valve clearance (last adjusted 2k miles ago).
Left cylinder was spot on. Right Cylinder wasn't far out of spec.: .1 I / .18 E, which I adjusted back to .15 E.
The spark plugs may give more of an indication as to what's going on, pics below. The plug from the right cylinder, where I've been hearing the knocking sound, is blackened/fouled with some soot on the electrodes (oil? carbon?). Is this a possible indication of oil leaking past the rings? 5k miles on these plugs.

I cleaned up the plugs, buttoned everything back up, and fired her up. Ambient temperature was a little higher than that at which I've heard the knocking sound before (about 58F vs 45-50F). I didn't hear the same knocking sound (from video in previous post) that had been appearing at cold start, which seemed hopeful. I broke out the mechanic's stethoscope, starting up at the valve cover, and working my way all the way down the cylinder. I heard some clatter at the top of the cover, which was expected, then, further down the cylinder, I heard a harsher, rhythmic metallic sound (about midway down the cylinder). The sound became less harsh as the engine warmed up. I didn't listen to the left side for comparison, but will when I get a chance.

Still no word from Piaggio. I expect I'll have to follow up regularly to get a response.

 

[john zibell]

Quick update, and some more information: When I had a chance, I checked valve clearance (last adjusted 2k miles ago).
Left cylinder was spot on. Right Cylinder wasn't far out of spec.: .1 I / .18 E, which I adjusted back to .15 E.
The spark plugs may give more of an indication as to what's going on: link to pictures. The plug from the right cylinder, where I've been hearing the knocking sound, is blackened/fouled with some soot on the electrodes (oil? carbon?). Is this a possible indication of oil leaking past the rings? 5k miles on these plugs.

I cleaned up the plugs, buttoned everything back up, and fired her up. Ambient temperature was a little higher than that at which I've heard the knocking sound before (about 58F vs 45-50F). I didn't hear the same knocking sound (from video in previous post) that had been appearing at cold start, which seemed hopeful. I broke out the mechanic's stethoscope, starting up at the valve cover, and working my way all the way down the cylinder. I heard some clatter at the top of the cover, which was expected, then, further down the cylinder, I heard a harsher, rythmic metallic sound (about midway down the cylinder). The sound became less harsh as the engine warmed up. I didn't listen to the left side for comparison, but will when I get a chance.

Still no word from Piaggio. I expect I'll have to follow up regularly to get a response.

Please post pictures to this site. I will not download to look at them. Also when linked to outside sites, they can disappear. All you have to do is attach the file(s).

 

[scottmastrocinque]

Interesting. I will be interested in reading your findings from your stethoscope work on the other side.

 

[Midnite]

Please post pictures to this site. I will not download to look at them. Also when linked to outside sites, they can disappear. All you have to do is attach the file(s).

Above now.

 

[john zibell]

Above now.

Thanks for putting the pictures in. Both are acceptable. One side is a little richer than the other. You may benefit from having the injectors cleaned to even out the mix on both sides. RC Engineering in California is the got to place for that.

 

[Warnzie]

The lambda sensors on *some* v85's are know to go a little haywire, even without causing a MIL alert, guess a good old ohms test on the 02 sensors could at least help with a process of elimination here

 

[Midnite]

Thanks for putting the pictures in. Both are acceptable. One side is a little richer than the other. You may benefit from having the injectors cleaned to even out the mix on both sides. RC Engineering in California is the got to place for that.

Good to hear that both are acceptable from your perspective. Thank you. Does it seem odd that an injector would need to be cleaned on a relatively new bike (10k miles in two years)? Trying to reconcile this with the other behavior reported above as well...

 

[john zibell]

Good to hear that both are acceptable from your perspective. Thank you. Does it seem odd that an injector would need to be cleaned on a relatively new bike (10k miles in two years)? Trying to reconcile this with the other behavior reported above as well...

You could have gotten a tank of not good fuel. Use top tier fuel to help keep injectors clean. The top tier fuels have additives to keep fuel systems clean.

 

[Midnite]

You could have gotten a tank of not good fuel. Use top tier fuel to help keep injectors clean. The top tier fuels have additives to keep fuel systems clean.

I've used nothing but the highest octane, top tier fuel in this bike (and all of my others). That's why I asked. Thank you for helping me think of all of the possibilities though. This hadn't occurred to me.

 

[john zibell]

I've used nothing but the highest octane, top tier fuel in this bike (and all of my others). That's why I asked. Thank you for helping me think of all of the possibilities though. This hadn't occurred to me.

Even a top tier station can have issues. If the pump filter hasn't been maintained then you could get fuel contamination from the underground tank.

 

[Midnite]

Interesting. I will be interested in reading your findings from your stethoscope work on the other side.

Weather was decent here today, so I fired up the V85 for a more thorough investigation with the stethoscope, and a quick test ride. With the right plug cleaned, and valves in spec, there was no audible knock that developed as before. When listening with the stethoscope, both cylinders sounded nearly the same from valve cover on down. Now I’m wondering if the plug fouling was bad enough to cause misfiring when cold, and if this is what I was mistaking for piston slap. And of course, what caused the fouling in the first place. Idle was smoother, as was acceleration through the revs while riding. The mystery continues…

 

[Raven]

My experience with modern spark plugs (iridium etc.) is that they either spark or they don't. You can't just clean them up with sandpaper, an old toothbrush, and some gas like in the old days.