Ugly Ugly Noise

[bigfatcat]

So, at 20 000 mi  my '95 gs has just started making a gravel-in-the-washingmachine noise .

But it runs as well as ever but I don't trust it now to ride it any distance.

Sounds like rocks being tumbled in a metal tub - comes and goes, sometimes at idle, usually not, often under load, when pulling away from a stop, steady cruise ...

Tried to get video/audio but wind noise masked the motor noise.

Here's when I first started it this morning, not warmed up -


http://s767.photobucket.com/user/bw40g93f2i/media/MOV006.mp4.html


Seems to idle fine - so does that rule out camshaft endfloat ?

[rexpepper651]

use a screw driver and hold it on to different parts of the case and head and put your ear up to it. this will help you find out to some degree where the noise is coming from.

[Buckmaw]

I assume your oil level is good?

[Janx101]

Goats!?

[robfriedenberger]

99.9% sure that if it sounds like gravel in the washing machine its goats......If its not goats your description is wrong lol

Drain and screen the oil to see how bad it is, and remove the left left side engine cover.

[bigfatcat]

Yep oil level fine, new oil change in fact just last week.

Yeah, i'm thinking 'Goats' ....  maybe Rotella melts the glue holding those magnets ...

Going to pull the cover in a few minutes - volt meter showed no change so maybe just one magnet got chewed up .

[rexpepper651]

goats???    wth..

[bigfatcat]

Well ....








Incipient GOATS, some epoxy chipped, a little more than last time I had the cover off years ago to change the leaky gasket ... not really enough missing to try jb weld ... no sign interference with stator/cover ... can't believe all that noise was just from this bit being banged off.

wonder how much I should sell this bike for, as is ...

[Atesz792]

Beware, some of that epoxy could have blocked an oil passage.

[robfriedenberger]

Uhh bike might be fine, check your starter clutch bolts I wouldn't worry about the epoxy


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[gsJack]

I think your starter clutch is loose just looking at the 3 bolts that hold it in your pics.  When tight they come thru the inside of the rotor and stick out a bit. Mine were recessed a bit and the clutch was very loose when I pulled it last week to fix.  A little work but very little cost and it's good as new again.  I pulled the cover last month and checked it just after the noise started and it looked OK then.  Here's pic of inside of my rotor just before I pulled it last week and pic of the clutch bolts that came out it:

[bigfatcat]

Beware, some of that epoxy could have blocked an oil passage.

YIKES !

I think your starter clutch is loose just looking at the 3 bolts that hold it in your pics.  When tight they come thru the inside of the rotor and stick out a bit. Mine were recessed a bit and the clutch was very loose when I pulled it last week to fix.  A little work but very little cost and it's good as new again.  I pulled the cover last month and checked it just after the noise started and it looked OK then.

In your case, Jack, was the noise intermittent or constant ?  Did you ride it much after you figured the problem ?  Where's the point of impact that makes the noise ?  All I see in your pics is what appear to be damaged threads on those bolts.

Trying to figure out how long I can ride this thing before it grenades ... ? That big crank bolt and all associated looks to be a bear to get off, and back on without breaking something.

[robfriedenberger]

Mine was any time under 2.5-3k over that it would stop, on gsjacks thread I stated that I've see larger displacement motors shoot connecting rods out of the crank case so I don't recommend riding it.


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[gsJack]

I first heard my noise a month and a half ago when coming to a stop it began.  I rode it about 10 miles back home and started checking for source of noise.  I looked for goats and starter drive rattle first under left cover and then cam chain, CCT, valve clearances, cam timing under top cover, and finally checked for  balancer shaft bearing knock under right side cover.  Put maybe another 10-20 miles on it during this period and ran it quite a bit in the garage also.

Searching again I found member Mach's thread on a similar noise and listened to his video and it sounded most like my noise so I pulled the left cover again this past week and the starter clutch was very loose by that time and was obviously the problem and I fixed it finishing yesterday.

Mach, Rob, and myself all agreed knock/rattle was always heard at idle hot or cold up to 2-3 maybe 4k rpm and never above that.  That's a little different from your description I think.

Mach thread with video:

http://gstwins.com/gsboard/index.php?topic=64272.msg764838#msg764838

Adidasguy's video on pulling Rotor:

http://gstwins.com/gsboard/index.php?topic=58403.msg768574#msg768574

Pulling the 12mm rotor bolt should be easy with an impact wrench, I struggled with a 18" 1/2 drive breaker bar and 6 point socket.  I put it in gear and blocked the rear wheel with a piece of wood across the swingarm and the clutch slipped just before the bolt broke loose.  I pulled it up to the slip point a couple times and gave it a jerk and got it, wasn't real easy.  Found pulling the rotor off the crankshaft taper not difficult using the 14mm bolt and 36mm spacer as described in Addidas's video.

I'm glad I fixed mine when I did, the starter clutch was getting much looser when I went back the 2nd time to check it.

[bigfatcat]

Mine was any time under 2.5-3k over that it would stop, on gsjacks thread I stated that I've see larger displacement motors shoot connecting rods out of the crank case so I don't recommend riding it.

YIKES !  AGAIN !

Mach, Rob, and myself all agreed knock/rattle was always heard at idle hot or cold up to 2-3 maybe 4k rpm and never above that.  That's a little different from your description I think.

Yeah, somewhat different than mine, in fact I barely heard the noise at all Saturday, not at idle at all, and just maybe a little around 4000 to 5000 revs - around the neighborhood, not really warmed up.

Wonder If I have (had) a stuck valve ?  These are interference motors right ?

[gsJack]

Mmmm maybe you do have a different problem.  Yes they are interference motors, I had a broken exhaust valve 10 years ago at about 20k miles on the clock when a tight bucket stuck open one very cold morning while cranking to start.  Discovered tight bucket at a 10k valve check when that valve wouldn't close completely on a cold engine.  Bucket loosened up as engine warmed in a minute or less and smoothed out and was good for the day so I let it go to see if it would wear in and free up. It didn't.  I suspect there are a lot of GSs out there with buckets that are tight when cold that aren't started in as cold weather as I did.

Check your buckets and see if you have a tight one, with cam lobe turned away from bucket you should be able to turn buckets with your finger tip with cold engine.  Mine was so tight I had to drive it out from the inside after pulling head with a long pin punch and heavy hammer, it went hard all the way.

When my starter clutch was very loose just before I pulled it to fix I could rotate it back and forth relative to the rotor about the amount of bolt hole clearance with my hands and even wiggle it a bit with hands.  First time I checked it just after noise started I couldn't budge it with hands and since the rotor retaining bolt was tight and all magnets were tight I closed it up and went on to check other items I mentioned.

[bigfatcat]

Mmmm maybe you do have a different problem.  Yes they are interference motors, I had a broken exhaust valve 10 years ago at about 20k miles on the clock when a tight bucket stuck open one very cold morning while cranking to start.  Discovered tight bucket at a 10k valve check when that valve wouldn't close completely on a cold engine.  Bucket loosened up as engine warmed in a minute or less and smoothed out and was good for the day so I let it go to see if it would wear in and free up. It didn't.  I suspect there are a lot of GSs out there with buckets that are tight when cold that aren't started in as cold weather as I did.

Check your buckets and see if you have a tight one, with cam lobe turned away from bucket you should be able to turn buckets with your finger tip with cold engine.  Mine was so tight I had to drive it out from the inside after pulling head with a long pin punch and heavy hammer, it went hard all the way.

When my starter clutch was very loose just before I pulled it to fix I could rotate it back and forth relative to the rotor about the amount of bolt hole clearance with my hands and even wiggle it a bit with hands.  First time I checked it just after noise started I couldn't budge it with hands and since the rotor retaining bolt was tight and all magnets were tight I closed it up and went on to check other items I mentioned.

Ok, this gives me something to work with, a couple of things to check out, keep an eye on ...

[bigfatcat]

Would someone look at this video and tell me ...
Is the starter gear supposed to be loose like this ?


http://s767.photobucket.com/user/bw40g93f2i/media/SUZIclutchstartr.mp4.html

[gsJack]

Yes that gear needs some side clearance, it just sits there stationary after the starter motor stops with the crank spinning inside it and the rotor/clutch spinning beside it.

After I bolted my starter clutch outer member tight to the rotor and mounted them along with that gear to the crank the gear had about that much clearance.  The clutch inner member is part of that gear and it's all lubed from inside with oil from the crank.

[bigfatcat]

Ok, good, that's what I thought, and the starter clutch itself seems absolutely tight to the rotor so all ok, and nothing rubbing on the case ...

I was thinking - Balance Shaft - but the right bearing is absolutely tight, and the left only seems to move practically none at all, a couple thousandths if that, with about 1 mm side to side play.

Interestingly,  I've found that as the bike warms up riding around -  the case and side covers begin to get HOT down low at the front, about where the BShaft bearings are - by placing my hand there as I'm riding ... within 10 minutes or so after engine start.  Don't know if it has always been so, but certainly years ago I noticed that after a ride the case/covers would be too hot to touch.  I guess normal for air cooled ? (imho the gs ( this bike at least) runs too hot, design flaw ? Cheap bearings?  Perhaps why they later added an oil cooler ? )   

Maybe peeps could post up re. how hot their gs cases run ?

But I digress.    At this point I'm thinking 'The Noise' may be cam chain / tensioner/ guide wear or something.