rattling sound, not a snake

[Ed Miller]

I was riding my R65 to work Friday morning, and upon going over a bumpy railroad crossing something started rattling.  It sounded to my panicking ears like a nut bouncing around in the motor somewhere.  It seemed to be related to the engine, as I came to a stop with the motor running and it continued.  So:  not driveline, anyway.  I don't remember if pulling in the clutch made any difference, though I suspect not or I would have noticed it.  

Then it stopped, and was intermittent, then stopped and I made it the rest of the way to work.  It was not rattling when I got to work.  I rode the bus home and drove my pickup to work Monday and took it home.  

I checked the valves to see if anything had happened in there, and while the exhaust clearances had closed up a little bit in the past few thousand miles nothing looked out of place.

My intention is to next change my timing chain, as I have the parts and the bike has 97,000 miles on it.  Original chain.  I checked the timing when I got it home and the mark does bounce around maybe 1/4", but I don't know if that is the same as the double image Snowbum mentions.  But on the way I'll be searching for any marks or clues that something has come loose and taken a ride through the area before coming to a rest.

Any other suggestions if I can't find anything out of ordinary in the timing chest?

[AlfromNH]

Have you started it since you got it home and confirmed the rattle is still there? Seems you could better assess the noise in the calm confines of the garage vs the side of the road.

Did the rattle vary with rpm? Any difference in the feel of the bike/engine?

[Tony Smith]

The fact that it is intermittent makes me suspect that you have a problem with your cam chain tensioner. It is not a big job to pull the front cover off, if you do not own a heat gun, borrow your girlfriend/boyfriend/wife/partner's hair dryer and use that I have on one occasion simply poured boiling water over the front case and that was sufficient to free it, but if you do that, leave the alternator rotor and bean can in place as you do not want water int he sump.
 
By the way, if you do take the font cover off to check the tensioner, unless you KNOW when the chain was last replaced and it has a reasonable life expectancy left, I would go ahead and change it anyway, likewise the guides if they show the slightest wear.

[Ed Miller]

Have you started it since you got it home and confirmed the rattle is still there? Seems you could better assess the noise in the calm confines of the garage vs the side of the road.

Did the rattle vary with rpm? Any difference in the feel of the bike/engine?

Yeah, I rode the bike up a ramp to load it in my pickup.  OK that doesn't sound right.  I rode it up a ramp onto a truck loading dock with a power ramp which a guy lowered onto my pickup.  I just rolled the bike down the ramp into my pickup.

Anyway, it did not rattle either when riding the bike to load it, nor last night when I was checking the timing.  The sound has disappeared for now.  

I thought it was varying with rpms, yes.  As for the feel of the engine, I'm like a hypochondriac.  I thought it felt different but can't put my finger on how, nor do I really trust that feeling.  

[Luca]

A timing light should give some indication of worn timing gear.

Might as well have a look in the oil pan too given your suspicions.

[nhmaf]

Yes, I'd drain the oil, and get a new pan gasket and drop the pan..   maybe the oil strainer screen from the oil pickup came off somehow?   Look for metal bits in the pan/oil, too.

The last time something like this happened to me after going over a big bump, I thought I busted something in the swingarm - turned out to be the nuts that were holding the rear fender onto the subframe had come off!  That was a welcome, easy fix!

[Luca]

turned out to be the nuts that were holding the rear fender onto the subframe had come off!

that reminds me of a buzz-rattling license plate I once had.  Had a kawasaki gas tank that was a bit loose make some horrendous noise too.

One other thing I could think of is that you maybe busted an exhaust hanger...  or have a baffle rattling around in the muffler.

[Bob_Roller]

I'd look the bike over real good, it may be something like an exhaust sytem, center stand, etc .... loose .

[Ed Miller]

thanks I always assume the worst I hope that you guys are right

[Bob_Roller]

I've got something loose inside the left muffler, it will rattle every once in a while, first time it happrned I was quite concerned .

Loose, or broken pivot bolts, missing springs on the center stand are another possibility .

[Bob_W]

I was scared when pulling into a gas station and hearing an awful noise. Fortunately, I was able to kill the engine and hear the noise continue. A road crew was gadding nearby.
I also had a tinny sounding rattle from the left rear while riding around my yard. I immediately stopped and put the bike on concrete to start work. When the left saddle bag was set on the pavement it rattled. It was my coffee pot still in the bag.
I hope you have as simple a solution.
Bob

[Ed Miller]

I've got something loose inside the left muffler, it will rattle every once in a while, first time it happrned I was quite concerned .

Loose, or broken pivot bolts, missing springs on the center stand are another possibility .

It looks like I'll have to drop my exhaust system to get the timing cover off, so I'll go ahead and remove the mufflers and give them a shake.  

[montmil]

Cousin Ed,

Pull the mufflers and give 'em a good shakin'. You might get lucky there.

When I did the timing chain replacement on my '81 R65, the x-over pipes were well bonded to the headers. After removing the header nuts and all clamps, the entire system laid down below the bike. It is a simple chore to rock the bike up on one leg of the centerstand and slide the pipes clear of the bike. An assistant is quite helpful.

Check the Photo Gallery for my photo essay on the timing chain replacement. TIP: Bring the cam sprocket's timing mark - a large dimple- to the 12 o'clock position. Mark the cranshaft's 6 o'clock sprocket tooth with white paint. Do this before removing any parts. How come? Glad you asked...

The crank sprocket has a scribed timing mark but you can't see it! Sneaky Motorrad chaps.

[Ed Miller]

Jerks.  The marks on my Triumph timing gears were easy enough to see.  

I don't need to completely remove the exhaust, just lower it a few inches.  Removing the stator really took me a long time.  It wouldn't pull free, and felt like it was hanging up on something.  I kept reading manuals, looking for pics, and stuff, then going back to it.  Finally I just tugged it off and didn't break anything.  The rotor was easy.

I'll renew my efforts on Sunday, even if I have to shorten my firewood cutting session.  Thanks for the heads-up on your photo gallery.

Edit:  wow your timing chest area is way cleaner than mine.  I mean the charging area, I guess.  I have all sorts of crud in there to wash off.  I need to double check that area to see if anything self destructed, as it seems there's a lot of particles.  

[montmil]

Yea, Ed. Clean it is. I had time to "rub n' buff" after I roasted a diode board by allowing one of the mechanics at the school district's garage to hook up jumper cables for me. Who knew? Red is positive. Black ain't. Magic smoke poofed outta the engine cover's vents.

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