Ok, so this is something I've only noticed recently, and I think I may be over-thinking this completely, but I've noticed that at low speed, say 25mph or so, if I zig-zag very quickly with the clutch pulled in, I get a feeling from the back end like a thump-clip-clip-pat-pat-pat-pat, almost like I'm doing this on knobbies.

Rear shock was replaced not too long ago with the Progressive. Rear tyre is an Avon Azzaro. I'm thinking it's the treads that are making that feeling, as I've had the wheel bearings checked, and they're fine, as are the swingarm bearings. I did also notice that if I rock the back wheel forward and backward a little, it makes a thunk-thunk sound. Last time the gear oil was changed was about 7500 miles ago, and I change it every 10k miles with Mobil-1 synthetic 80-90wt. Could it be that it's just the treads doing this? I don't remember it feeling like that when I had the Dunlops or the Pirellis on it. Bike has just over 63k on the clock now.

Also, for as long as I've had this, that thunk noise has been present in the rear wheel if I rock it back and forth, so not sure if this is normal or not...

What mileage on the Azaro?

Patient: So Doc when I do this it hurts?

Doctor: Well don't do that anymore and it will not hurt. Please pay the Receptionist on your way out.

The clunk sounds like drive line slack an is normal.

The pat pat sound is likely the tire tread now that it is worn.

It is possible to have the front "U" joint failing.  They do not fail often, but it is not heard of.  Since the sensations change when pulling in the clutch and unloading the drive train, this could be a place to check.

It is possible to have the front "U" joint failing.  They do not fail often, but it is not heard of.  Since the sensations change when pulling in the clutch and unloading the drive train, this could be a place to check.

Or drive splines in the wheel getting worn out?

Or drive splines in the wheel getting worn out?

A big plus 1 on the drive splines on the hub. 63k is more then enough miles to cause it. Many on here have had to replace the hub spline, mine went S @ 70k.
It is an easy check, but trust me, you must remove the hub from the wheel to do a good look see. Trying to look at it while on only lets you see the outside edge, and it is the inner guts that wears out.
See pics below for reference. Hope this helps.
Ride safe all.
Greg

HEY you're toothless. 

HEY you're toothless. 

"WAS" toothless, now I have all my choppers.
RSA,
Greg

I've been having the same issues that you described for a while. It started about 4k miles ago before I changed the rear tire from a Dunlop to Azaro so I don't think it was the tire. Last winter I had to repair the bevel-drive gasket and had a chance to inspect/service everything from there back and found nothing obvious other than a very, very slight notchiness in the u-joint.
I made note of it then buttoned everything up. Symptoms as you describe is still there. I'm going to re-assess the u-joint
and go from there. Hope this is helpful.
I can use some advice on the repair of the existing joint or replacement source. Thanks.
-Rich

I can use some advice on the repair of the existing joint or replacement source. Thanks.
-Rich

I believe both stateside and overseas, extensive research was accomplished to find a replacement aftermarket u-joint. None could be found, it appears it is proprietary to Kawi.
So servicing the u-joint is very minimal, if damaged, either a good used one or a new one from Kawi are the options for replacement.

  Don't think I've ever heard of a u-joint going bad on a Concours. They usually last forever. I suppose if the rubber boot protecting the u-joint went bad and allowed dirt in the joint it might go bad.
   The slip joint near the final drive could cause problems if not lubed on occasion.

If we ever get some bad weather here in Ohio, I'm going to breakdown the rear end just because. Lube what needs lubed, adjust what needs adjustment, and inspect my now 11 yr. old baby.
Maybe a shock re-build is in the future also. And definatly a new rear skin.
Around here, Winter, at least when it hits, is TLC time.
Ride safer all.
Greg

Been having the same "problem" with the weather hear in Jersey. Lotsa nice riding days this winter and road aren't covered with salt and grit. Gunna go out Sunday (mostly sunny, 40 deg.) for a ride while everyone else is preoccupied with football. One of the best riding days of the year. I'll attack the u-joint issue when the next snowstorm comes.
Rich

>>>SNIP<<< but I've noticed that at low speed, say 25mph or so, if I zig-zag very quickly with the clutch pulled in, I get a feeling from the back end like a thump-clip-clip-pat-pat-pat-pat, almost like I'm doing this on knobbies.

 Rear tyre is an Avon Azzaro. I'm thinking it's the treads that are making that feeling, as I've had the wheel bearings checked, and they're fine, as are the swingarm bearings.

How many miles is on the rear Avon, & is it cupped?  This will give you that "riding on the knobbies" feeling.  Just re-profile the tire w/ a wood rasp or electric sander. The other option would be a trip to the nearest twisty road section which would allow you to scrub off the high spots.

Thanks for all the input!

Rear tyre has about 1800 miles on it. No cupping that I can see. Checked the boot, that looks good. Pulled the rear wheel and just had a look at the teeth, and from what I can see, they're worn, but only slightly. The teeth definitely look better than what I've seen in some other photos on the subject. May have to take a pic and see what you all think. I did, however, fiddle with something else: tyre pressure. At 42psi on the rear, I get that feeling. At 39/40, it goes away.

Best I can figure is it's the treads making the noise/feeling. 

So, it seems that the rear tyre is indeed cupped. Having only ever seen cupping on the Dunlops, I didn't really know what to look for on the Avon Azaro. I ran my fingers along it and it's definitely not perfectly round anymore. I've also noticed now that the whole bike feels nervous at speed, straight or going round corners. Fiddled with the damping on the Progressive rear shock to see if that was the issue, made no real difference if it was at a 3, 4, or 5. All the fasteners are tight, and there's no wiggle or looseness to the swingarm.

Anyone ever see cupping on an Azaro rear before? I thought these were supposed to be the best tyres going. I only have about 3000 miles on both the tyre and the shock, so I don't think either could be totally faulty...could they?

Yes the Azaro on my bike did cup around 4k but only a little bit and did not upset the bike any,
however im now on a Shinko 777 with over 8k on it and a front AM26 roadrider with over 15k and now my bike wants to go into a tank slapper on deceleration around 40mph, but that's only if i'm trying to look cool and ride with no hand, i no longer care about looking cool and long as my hands are on the bars its fine, i'm sure its the front tire causing this and it is slightly cupped and the rear even feels slightly cupped as well but there is still lots of miles left on both tires so im gonna ride it till it gets to the wear bars then change them like i always do.

Is it definately cupping as you describe it or the tyre starting to square off? Never known a rear to cup in all the years I've run the Azaro rear but IMO squaring off can give you the same feeling.

Is it definately cupping as you describe it or the tyre starting to square off? Never known a rear to cup in all the years I've run the Azaro rear but IMO squaring off can give you the same feeling.

Does seem to be squaring a little. I just noticed that if I run my hand over it, it feels like the treads are higher in the front of the tread than the back of its antecedent. Hope that makes sense. It's like it's not smooth all the way around.

What kind of life can I expect from an Azaro? I'm about 360lbs with all my gear on, so I'd not be surprised at all if I'm wearing tyres out faster.

I'm about 260 and my Azaro had 5,730 miles on it when i changed it, i could have went another 250-500 or so but i like to change tires once they down down close to the wear bars. just keep an eye on the wear bumps in the center of the tire, i also remember mine did cup kind of square but the shinko 777 i have now is seems to be cupping more roundish. you probably can expect about 5 to 6k on the azaro. try the 777 next time around and i think you will be happy with it, i sure am. but i guess it depends on the rider and bike and riding style.