Squeak from Motor

[JoeV11]

This can't be good.

 

The other day I was riding home and as I turned into the road leading to my house I heard a loud squeaking noise from the motor. I pulled in the clutch and it kept squeaking. It seemed to be idling rough but it kept running if I gave it gas. Since I was only about three miles from home I drove it back slowly, but it wasn't running well, needing more gas than usual. I know I was overdue for an oil change (8k miles on synthetic), so my thoughts immediately went to cam or rockers or worse yet, crank bearings. A week later I started it and the noise hadn't gone away. The bike has about 13K miles on it.

 

Finally last night I checked the valve clearances and they were OK within .001" (they were due for adjustment anyway). I pulled the oil pan and there wasn't any great quantities or large bits of metal, just a slight coating of very fine powder in the center valley. The cam lobes look normal, and the rod bearings aren't noticeably loose by hand. Tonight I thought maybe the alternator was rubbing but it was fine with at least .010" clearance to all of the stator coils, and no signs on the cover. I spun the motor by hand with the alternator nut and heard nothing abnormal except a very slight clunk if I rock the crank back and forth and only when it's pointing straight down (not bdc on either cylinder). That may be odd or may be normal, I don't know. The next thing is to start pulling bearing caps, but I thought I'd ask the internet first.

 

Has anyone heard this squeaking sound before? Any ideas what it could be? Should I just add fresh oil and hope for the best?

 

Thanks in advance, Joe

[luhbo]

Fuel pump?

[Guzzi2Go]

Fuel pump?

Would be heard with engine off, wouldn't it?

[docc]

No chance it could be a "whistling" sound as might happen if the air boots cracked, came loose, or the vacuum taps were leaking?

[JoeV11]

No chance it could be a "whistling" sound as might happen if the air boots cracked, came loose, or the vacuum taps were leaking?

 

I think it was a squeak. It's been a few weeks now. I'll check those things anyway.

 

The fuel pump doesn't make the noise when I turn on the key. I just tried it three times in a row. Thanks, though.

 

I remember going on a trip when I first got the bike and it made a similar noise for a minute or so. I thought it came from the front of the motor at the time. This also sounds like the front or middle of the motor. That's why I checked the alternator. Could it be a cam bearing or the cam chain? A search revealed the chain lasts 50K miles or longer.

 

The motor is still apart. It's supposed to rain all next week so I'll get back into it again.

 

Thanks again. Joe

[JoeV11]

No chance it could be a "whistling" sound as might happen if the air boots cracked, came loose, or the vacuum taps were leaking?

 

Well Doc you were right! The left side was pretty loose so I knew I was onto something. But the right side was the problem:

 

 

 

That's some air leak! Tomorrow's test ride will confirm it.

[jrt]

Cool- I hope that's it.

 

Your description of the clearances, finings in the pan, etc. sound pretty normal. 8K is IMO pushing it on oil but realistically, it is probably just fine.

Please follow up tomorrow with how it runs- and good luck!

[docc]

Looks like good news!

 

With the boot bumped off like that, it's time to check a full tune - up (valve adjustment/ plugs/ Throttle Body Balance, and idle setting), once you get the boots cinched back up.

[luhbo]

 

... I think it was a squeak. It's been a few weeks now...

 

Anybody still in doubt whether they're robust bikes or not?

 

hubert

[The Monkey]

Their robust for Italian machinery alright. Its just the Rob and the Bust that triggers conniption.

[Baldini]

conniption?

[The Monkey]

A fit of anger or other violent emotion= conniption

 

I never got a squeek outa mine they would just back right off with the resulting snort and pop. They wouldnt stay put. Had to replace the boots, I guess the rubber just gets sketchy after so many temperature fluctuations.

[mznyc]

conniption?

Two countries separated by a common language!

Be in Scotland Saturday for a week and there will be many "excuse me,pardon,I'm sorry's " and that'll just be trying to understand my girlfriend

[JoeV11]

Ha you guys are too funny!

 

The bike ran great the other day, just like nothing happened. In fact better because I adjusted the valves, changed spark plugs and the oil. Also, I re-checked the mileage - only 5K since last oil change.

 

Now I just have to wash and wax it before putting it away for winter.

Joe