Rear drive question

[Jeepjohn]

I'm new around here (a second time). I have a Black Eagle that the rear drive shaft area makes a clunking noise when it's hot. It goes away when cool. I took it to Sloans in Murfreesboro and told them what I was noticing. They said it's fine.
Is it? I wish I could put a video on here I took when it was hot.
Thank you for insight

[oldbike54]

I'm new around here (a second time). I have a Black Eagle that the rear drive shaft area makes a clunking noise when it's hot. It goes away when cool. I took it to Sloans in Murfreesboro and told them what I was noticing. They said it's fine.
Is it? I wish I could put a video on here I took when it was hot.
Thank you for insight

 If you were running it on the centerstand it would have made all kinds of noise .

 Dusty

[John A]

Must be new if it's quiet cold if you run it on the center stand . Do a search for Pete R's poetic description  of why not to do that.

[oldbike54]

Must be new if it's quiet cold if you run it on the center stand . Do a search for Pete R's poetic description  of why not to do that.

 That would be Pete Roper , and it might not be available . Let's suffice that Pete strongly admonishes not to do so 

 Dusty

[pete roper]

When does it make this 'Clunking' noise? When you engage first from neutral? When you change gears on the move? When you are riding along?

[Jeepjohn]

I was pushing it into the garag in neutral. I heard "clunky" noise. I had never heard it do that before. It has about 2500 miles on it. I put it on the center stand and rotated it by hand. It seemed to get tight and it would make the clunk sound. I let it cool off (I had just ridden several hours), the clunk went away when cool

[Jeepjohn]

Riding I have noticed nothing. No noises (that I can tell), no vibration or anything that "feels" weird. I double checked the fluid level in the final drive case and it came out of the "level" hole/plug/screw

[mar54]

perhaps a noise of rear brake pads

[pete roper]

The fact that you are feeling a resistance to rotation is a bit worrying.

[Triple Jim]

Mar54 pointed out that the noise could be brake pads clunking as the direction of rotation changes, and since dragging brakes could cause resistance to rotation, it might be a good idea to unbolt the caliper and tie it out of the way, and see if there is still drag and clunking.

[Jeepjohn]

it's most assuredly in the drive shaft. If a u joint fails, can the back tire lock? Or should it just break free and have no power to the wheel?

[Old Jock]

If a UJ fails then lock up is certainly a possibility

Is there play in the UJ?

I'm not sure what type of UJ you have some are greasable if so I'd certainly check that its got fresh grease

I agree with Pete (I'd be dead mat if I didn't) that any resistance to rotation, should be looked into

Usually when UJs start to go you feel a vibration through the pegs which gradually gets worse.

Triple Jim's idea is certainly good too wish I had thought of that to eliminate a possibility

[Jeepjohn]

It has to have gotten warm to show up. I'm kind of concerned about riding it now to try to check things.

[acogoff]

     You may be able to loosen the rear drive shaft boot clamp and roll boot forward onto the transmission's stub so you can see if there is excess play in ujoint as you move the rear wheel back and forth by hand.  Pulling the rear drive and swingarm off to check the ujoint would be the better way to go though.

[Daniel Kalal]

You may be able to loosen the rear drive shaft boot...

Doesn't this bike have the more recent elongated dual-cardan (dog-bone) and not the compact version that most of us are acquainted with that was used since the days of the Ambassador?  I'm not sure a peek under the boot would help much.

The clunk-clunk.... Was it exactly one "clunk" per rotation of the wheel (which would mean something in the box or a wheel bearing or brake disk) or was it more frequent?  How many "clunks" per rotation of the wheel?

[pete roper]

The later, extended, twin coupling driveshafts have proven super reliable. Doesn't mean they can't fail but if it has it will be an exceptional occurrence.

Pete

[Jeepjohn]

The clunks were about every 1/8 of a wheel turn or so. But, it's cool now and quiet. I'm unsure how far I need to go to heat it up. John Zibell heard it and believed it to be the "velocity joint". We took the motorcycle to Sloans. When we got there, it was quiet. We told them what it was doing when hot, and after cooling it's quiet. They checked it and said its fine. I brought it home. Rode for about an hour, and it was clunking when pushed in neutral. I let it cool for an hour and it was quiet again.

[Tom H]

Two thoughts to try to narrow this down:

For those that know the rear drive gear ratio. 1/8th turn of the wheel equals about how many revs at the U joint? 1/2 shaft rev could be 1 bad cap on the cross as it passes a certain point?

You mentioned when you push the hot bike the noise is there. Have you sat on it, pushed it and still have the same noise? Try two people on it and a buddy give the bike a push. No weight equals more angle on the U joint, more weight it should flatten out.

Good luck!!
Tom

[Jeepjohn]

I've realized my unanswerable question is this. If the dealer HAS to hear it hot to fix it, I have to get it there either hot or broken. The nearest dealer to me is in Atlanta, and that's about 2-3 hours away. Im kind of afraid to ride it that far (maybe unfounded, but I don't want the rear tire to lock while I'm riding).The reason I want to take it to a dealer is because I bought it "new" (it was four yrs old)5 months ago, and figure it should be covered under warranty. So, how do I get the dealer to be aware of what's going on? Risk getting three hour ride out of it?

[Daniel Kalal]

...John Zibell heard it and believed it to be the "velocity joint"...

Of course, the Guzzi drive shaft has nothing as fancy as a CV-joint.

Is John Z near you?  He's a known Guzzi guy.  On the older Tonti frames, it requires pulling the swing-arm to get to the U-joint.  Not an especially terrible job, but not what you probably want to do on a bike under warrantee.  I've no experience with the later version; perhaps it's an even easier job...

If I were to gamble, I'd say you'd be fine to ride it that distance.  On the other hand, I am one that has had a U-joint fail (the older style) and I left the dashed skid marks from the frozen/free/frozen/free rear wheel to show for it.

[Tom H]

I've realized my unanswerable question is this. If the dealer HAS to hear it hot to fix it, I have to get it there either hot or broken. The nearest dealer to me is in Atlanta, and that's about 2-3 hours away. Im kind of afraid to ride it that far (maybe unfounded, but I don't want the rear tire to lock while I'm riding).The reason I want to take it to a dealer is because I bought it "new" (it was four yrs old)5 months ago, and figure it should be covered under warranty. So, how do I get the dealer to be aware of what's going on? Risk getting three hour ride out of it?

It sounds like you have answered  the question. It's a new bike that is under warranty, take it to the dealer on a trailer. or have them pick it up. If this dealer won't help you and it's a factory warranty, try another dealer.

IMHO and just knowing loops, I would say it's a U joint. As mentioned the swing arm has to come off to find out.

If your not sure about riding it...DON"T...... Had a bike seize at 70mph, not a thing I want to do again. Amazing what rain groves carve into a tire.

You have a nice bike, get them to fix it or take the bike back and refund your money!

Hope this helps and all works out for you!!! When right, Guzzi's are great bikes!!
Tom

[Huzo]

If you were running it on the centerstand it would have made all kinds of noise .

 Dusty

Now you know better than to say that Dusty one.

[Old Jock]

I freely admit I do not know the newer models

I see posters stating that the newer models have a dual UJ if I am understanding correctly

Do the UJs need to be positioned in a certain angular configuration relative to each other?

That was the case for my Daytona and also for my Sfida, which both ran/run double UJs on the drive shaft.

Although I'm probably clutching at straws and the fault would most likely manifest itself both hot and cold, but are UJs aligned correctly relative to each other?

Is there any sort of shock spring or other device? The Daytona ran a spring in the shaft, is all Ok there.

I'm just throwing out ideas, the more knowledgeable might tell me that these ideas are rubbish and that's fair enough, I just thought I'd post when I remembered experience from similar setups.

[Wayne Orwig]

The later, extended, twin coupling driveshafts have proven super reliable. Doesn't mean they can't fail but if it has it will be an exceptional occurrence.

I had one of the new ones fail.
One of the bearings locked up. I suspect a roller or two inside disintegrated. Anyway, that caused the bike to 'jack' up and down a little since, it locked up slightly out of alignment.
Since the splines had some wear, I replaced the entire unit. Not cheap.

[LaMojo]

I'd first make sure your 5 year old bike is definitely under warranty.  In writing.

I believe the Black Eagle is basically a Bassa with black matte paint thus having the identical mechanics as all of the California models- 1 U-joint, 5 speed trans. etc.   My '98 EV has a slight clunk from the rear wheel if you put the bike on the center stand and rock the rear wheel slightly back and forth, but that is due to the lash in the pinion/crown gears. It also has a noticeable drag on rotation but its been that way for years. Indications point to the U-joint or the friction fit within the carrier bearing inner race, but I would check the lubricant level in the angle drive first.  I would also check to see if the angle drive housing is warm or hot to the touch after a long, warm up ride.  If hot, then the gear lash may be too close, bearing problems or incorrect wheel spacer on the axle.

Hard to diagnose intermittent problems especially not being there.
 

[Daniel Kalal]

...the identical mechanics as all of the California models...

Earlier Cals (and all previous Tonti bikes) had the top (short) version, and later and final Cals the bottom (longer) one.  Of course, both are dual Cardan joints (that is, two U-joints in series)



(images clipped from M.G. Cycle)

[LaMojo]

OK, thanks for the cardan joint lesson Daniel!

[Daniel Kalal]

OK, thanks for the cardan joint lesson Daniel!

Gerolamo Cardano was born in Pavia, Italy--not too terribly far from Mandello del Lario.  OK; that's the last lesson.

[rocker59]

I believe the Black Eagle is basically a Bassa with black matte paint thus having the identical mechanics as all of the California models- 1 U-joint, 5 speed trans. etc.   

FWIW, Black Eagle is a stripped-down California Vintage.

[John A]

Well things do go wrong and you won't trust it until it's resolved. Could be a u joint carrier bearing, they talk to you when they go away.