Bad engine vibration after a long ride / I think I broke her. :(

Raydr · April 13, 2012, 10:47:29 AM

SHORT VERSION:
She died on me after 20 miles at 85MPH, pulled over. Started her, she idled for a 10 seconds then screeched to a half (like metal on metal almost). Checked oil (looks okay), realized that I'd left choke half on. Let her sit for a few, started her up, she seems to run fine now but with a bad, almost unbearable engine vibration (even at idle, worst around 5K RPM). What did I do to her?

LONG VERSION:
I have a 30ish mile commute to work, 98% of it which is highway at good speed (80-85MPH). This morning I was in just a little bit of a rush, so I started her up, set her to half choke, waited a minute, and rode off.

Today is particularly windy and I was riding in to it, so I didn't think much when I would have trouble WOTing her to pass. However, about halfway through my ride I noticed she was becoming weaker and weaker - I could maintain speed, but accelerating was a struggle. After a few more minutes she started trying to sputter out (at 75MPH!) so I pulled off the road and she immediately died. I started her up, and she ran for a few seconds then died with what sounded like a metal on metal screeching halt.

"Oh F#%!", I'm thinking as I rush to check the oil. At this point I notice the oil cap is much hotter than it normally feels. I take it off, there's a little bit of smoke coming out (I think this is normal?) and the oil level looks fine. I start looking all around the bike to try and find something wrong and realize that I'd left the choke half on during the ride.

I put the choke back to normal, start her up, and she runs fine, except now I notice that she's got a new vibration at idle. I jump on the bike, ride in to the office, and she rides normal, except she vibrates like crazy. Noticeable at idle, worst at 5000-5500 RPM. This vibration is definitely strong enough that I can see it vibrating the bike to pieces.

First, any ideas what happened? Did I massively overheat the engine by leaving the choke on halfway?

Second, what is this vibration and how to I fix it?

Finally, can I ride her home tonight or should I trailer her home?

Thanks.

Kijona · April 13, 2012, 10:54:00 AM

May have fouled the plugs. Might want to check them and/or replace them. They're 2.49 a piece at Auto Zone.

Raydr · April 13, 2012, 10:57:13 AM

Quote from: Kijona on April 13, 2012, 10:54:00 AM
May have fouled the plugs. Might want to check them and/or replace them. They're 2.49 a piece at Auto Zone.

I'm thinking this is an option as well as possibly changing out the oil - I'm wondering if any gas made its way into the oil/engine.

Twisted · April 13, 2012, 12:43:30 PM

Metal on metal noises are never a good thing. Sounds like you could have thrown a magnet. Search for goats or look at this thread - http://gstwins.com/gsboard/index.php?topic=58197.msg659893#msg659893

Raydr · April 13, 2012, 01:25:12 PM

Quote from: Twisted on April 13, 2012, 12:43:30 PM
Sounds like you could have thrown a magnet. Search for goats or look at this thread

I really don't like you right now.

Wondering if I should risk the ride home...

Kijona · April 13, 2012, 01:30:31 PM

Wow, somehow I missed the bit about the metal-on-metal sound. EEK

Your next option would be check the plugs and then drain the oil out and check for bits of metal in the bottom of the drain pan. Remove the filter and take it apart, check for metal in the filter element as well.

Raydr · April 13, 2012, 02:56:59 PM

Update: Got her home, slowly but surely. She's running okay except for the vibration.

Checked the oil - I missed it earlier but it's very liquid - I think a lot of gas got mixed in. (I didn't notice when I originally checked because it was hot and seemed okay. I checked several hours later after she was completely cold and noticed the oil was very viscous.)

Heading out to get some supplies to flush the oil and check the stator/rotor.

Wish me luck.

Raydr · April 13, 2012, 03:11:21 PM

Hmm - I might not be prepared. Am I going to need to replace a gasket of any sort once I get into the stator/rotor area?

Kijona · April 13, 2012, 03:20:00 PM

Quote from: Raydr on April 13, 2012, 02:56:59 PM
Update: Got her home, slowly but surely. She's running okay except for the vibration.

Checked the oil - I missed it earlier but it's very liquid - I think a lot of gas got mixed in. (I didn't notice when I originally checked because it was hot and seemed okay. I checked several hours later after she was completely cold and noticed the oil was very viscous.)

Heading out to get some supplies to flush the oil and check the stator/rotor.

Wish me luck.

I would just check the oil and filter first. There will be bits of metal in the oil if anything broke, more than likely. It's the easier of the two.

Also, I noticed that on both my GS's. The oil seems to be very viscous.

You will need a new gasket after removing the side cover. You'll also need a razor blade to remove the old gasket bits unless you get extremely lucky and the gasket hasn't fused to the metal.

Take a few sniffs of the dipstick - if it's got a LOT of gas in it it'll have a very pronounced smell. Otherwise, used motor oil just smells somewhat like burnt matches.

Kijona · April 13, 2012, 03:28:02 PM

I also meant to mention that a bit of smoke coming out of the oil fill hole is normal. It's also normal for it to get so hot you can't touch it.

The only thing that is concerning me is the screeching sound you were describing. The only thing I can think of that would make such a sound is a bearing...in which case...motor is not long for this world.

If the oil was in fact thinned out, it's possible the sound was the clutch but that oil would have to be almost 50/50 gas and oil for that to happen. Can't really say for sure...just shooting in the dark at possibilities.

dropitlow88 · April 13, 2012, 03:43:29 PM

Bearing screech would almost surely be accompanied by knocking afterwards.

Raydr · April 13, 2012, 03:49:56 PM

Okay, here's an update: pulled the oil plug and what poured out is not what I'd call oil. It just came out like water, and it smells gassy. I'm thinking that a hell of a lot of gas got into the engine from me running close to WOT for 25 minutes with the choke at least half on.

Pulled the stator cover and although the side epoxy/glue/whatever is gone, the magnets are in good shape. Here are some pictures: http://imgur.com/a/tcr6l

Any thoughts with this new info?

dropitlow88 · April 13, 2012, 03:55:35 PM

Did the oil look pearlescent? Shiny flakes?

Raydr · April 13, 2012, 04:02:01 PM

Quote from: dropitlow88 on April 13, 2012, 03:55:35 PM
Did the oil look pearlescent? Shiny flakes?

Yes on the pearlescent, not sure about shiny flakes. I haven't stuck my hand in to it yet but I haven't detected any metal yet. I'm going to stick a hard drive magnet I have into the oil and see if it picks up anything.

Here are images:
http://imgur.com/a/tcr6l

ohgood · April 13, 2012, 04:04:05 PM

Quote from: Raydr on April 13, 2012, 03:49:56 PM
Okay, here's an update: pulled the oil plug and what poured out is not what I'd call oil. It just came out like water, and it smells gassy. I'm thinking that a hell of a lot of gas got into the engine from me running close to WOT for 25 minutes with the choke at least half on.

Pulled the stator cover and although the side epoxy/glue/whatever is gone, the magnets are in good shape. Here are some pictures: http://imgur.com/a/tcr6l

Any thoughts with this new info?

Not sure why you're paranoid about the choke... but anyway...

adidasguy · April 13, 2012, 04:09:13 PM

Check compression. May have blown a ring. That might have been the metal screeching sound. That would account for low power and gas getting into the oil.

Raydr · April 13, 2012, 04:11:40 PM

Quote from: ohgood on April 13, 2012, 04:04:05 PM
Not sure why you're paranoid about the choke... but anyway...

My understanding is that running for a long time with the choke on could pull excess fuel in which eventually makes it into the engine. Is this wrong?

adidasguy · April 13, 2012, 04:15:48 PM

It runs richer but it burns. If any doesn't burn (as in a bad spark plug) it gets blown out the exhaust.
Oil can't get from intake and pistons into the oil unless something is broken.

dropitlow88 · April 13, 2012, 04:18:05 PM

Your magnet won't pick up bearing material. It's an aluminum alloy. That's more than likely what has been damaged from running the gas thinned oil. How old is the oil? And no, all excess unburned gas from running the choke will go through the exhaust. My guess is the carbs flooded the engine at some point. Or you have terrible blow by with a combined overly rich problem. But it would take a long time for gas to accumulate in the oil this way. Change the oil and filter, run it for a little bit and change it again to help excavate/capture metallic particles in the engine. Keep an eye on the oil level and quality.

Raydr · April 13, 2012, 04:26:59 PM

The oil and plugs are two weeks old.

News:

Bad engine vibration after a long ride / I think I broke her. :(