Rear End Clunk?????

[Craig N. AZ]

The bike is a 1998 Tourer with about 65K mi. and has developed a loud clunk that sounds like it is coming from the rear of the bike. The clunking is not a set pattern but is frequent and random. It sounds like something is binding then releasing but after two times thru the drive line, I can’t find anything wrong. I can’t duplicate the problem with the wheel off the ground with the bike running or just spinning it by hand. The clunking is still present when coasting with the engine off so it must be something that turns with the wheel. No work was done previous to the clunking starting and I had just returned from a 8K mi. trip around the country pulling a camping trailer. Everything was torqued properly and in the correct order. I may just replace the wheel bearing to see if that is the problem but don’t really want to open the final drive yet. This one has really got me stumped.

What I’ve done so far:

Went thru the drive line, down to the u-joint, and cleaned and lubed everything. (2 times)
Checked wheel bearings – Moved smoothly.
Replaced final drive oil. – It was clean with no metal shavings.
All splines look perfect.
Replaced u-joint. (2nd time thru)
Turned final drive by hand and it moved smooth and free. (installed on bike without wheel)
Swingarm seems firm.

Any ideas?

[DFragn]

Did you check the wheel dampeners for excessive movement? Enough lash could cause noise in the drive line and will sound off with some irregularity. They're under the star drive [lifts out] & the dampener cover plate.

How 'bout the rear caliper?

[Ricky-D]

Ok Craig:

Are you saying all the inspection you have listed, has been done since taking the trip?

Or that list is what you have done in preparation, prior to going on the trip.

***

[Craig N. AZ]

Did you check the wheel dampeners for excessive movement? Enough lash could cause noise in the drive line and will sound off with some irregularity. They're under the star drive [lifts out] & the dampener cover plate.

How 'bout the rear caliper?

The rear caliper moves freely and I did replace the brake pads the first time thru. The dampeners have a little play in them but that would just cause some slop in the drive but I don’t think it could cause the load clunk. The clunking started weeks after I returned from my trip.

[Craig N. AZ]

Ok Craig:

Are you saying all the inspection you have listed, has been done since taking the trip?

Or that list is what you have done in preparation, prior to going on the trip.

***

All this was done in the last few days.

[Daniel Meyer]

Ok Craig:

Are you saying all the inspection you have listed, has been done since taking the trip?

Or that list is what you have done in preparation, prior to going on the trip.

***

All this was done in the last few days.

You don't mention the pinion cup/joint specifically...did you pull the shaft out of the pinion cup and check it out?

[Craig N. AZ]

Ok Craig:

Are you saying all the inspection you have listed, has been done since taking the trip?

Or that list is what you have done in preparation, prior to going on the trip.

***

All this was done in the last few days.

You don't mention the pinion cup/joint specifically...did you pull the shaft out of the pinion cup and check it out?

Yes, and it looked good too.

[Daniel Meyer]

Ok Craig:

Are you saying all the inspection you have listed, has been done since taking the trip?

Or that list is what you have done in preparation, prior to going on the trip.

***

All this was done in the last few days.

You don't mention the pinion cup/joint specifically...did you pull the shaft out of the pinion cup and check it out?

Yes, and it looked good too.

Could it be the suspension instead of driveline? I had a stock shock that would bind and clunk...

[Chrisj CMA]

Replace the left rear bearing.  BUT!!!!!!  take a good look at the seat cup for the bearing.  I dealt with a rear endc sound that drove us crazy until we saw that the bearing seat was wallowed ot enough to let the bearing actually wobble back and forth.......a new wheel will be needed if that is the case.

[Kylenav]

I just had a rear vibration/noise and replaced a faulty right side rear bearing (replaced them both but the right side was the bad one).  To really "test" the bearing you have to apply a bit of pressure from side to side when you're spinning it, or at least I had to.  When I just spun it around it was quiet and smooth, soon as I applied some pressure and spun it, it would seize right up.  I tore it apart and there was pitting and grooves in one of the races.  Unless the seat is indeed bad then a bad bearing would be more frequent and you could duplicate it easier by leaning the bike from side to side while riding.  And a bearing isn't likely to make a binding and crunching noise and still work, at all.  Once it gets to that point it's pretty much a guaranteed game over for the bearing.

I'm no expert by any means but that is my experience with the bearings.

You may consider riding 2 up to try and see if a passenger can get a better sense of where the noise and vibration is coming from. May help, don't see what it could hurt.

Still fairly new to the fat lady but figured I've asked for enough help and maybe, just maybe my 2 cents will help ya out!

[Craig N. AZ]

Replace the left rear bearing.  BUT!!!!!!  take a good look at the seat cup for the bearing.  I dealt with a rear endc sound that drove us crazy until we saw that the bearing seat was wallowed ot enough to let the bearing actually wobble back and forth.......a new wheel will be needed if that is the case.

Chris – I will probably replace the left bearing the next time I pull it apart. I bought extra bearing to take on road trips so I already have it. Thanks.

Daniel – I had considered the shocks and I will put the stock shocks back on to see if that makes a difference. I now have the Progressive 440’s and noticed extra dirt around the bottom of the right one but thought that was from a long road trip but it could be a bad shock. Both shocks seemed OK when I adjusted them the other day.

[Craig N. AZ]

I hate it when someone asks for help with a  problem and then doesn’t post the resolution to the problem.  I’ve been guilty of this so I wanted to remedy this.  My clunking/grinding in the rear end  turned out to be the left rear bearing. I couldn’t get it to test bad until I drove out the bearings, so I replaced both rear wheel bearing to be safe. Everything is good now.

[tank_post142]

Thanks! 

[eric in md]

good news ..

[gordonv]

I hate it when someone asks for help with a  problem and then doesn’t post the resolution to the problem.  I’ve been guilty of this so I wanted to remedy this.  My clunking/grinding in the rear end  turned out to be the left rear bearing. I couldn’t get it to test bad until I drove out the bearings, so I replaced both rear wheel bearing to be safe. Everything is good now.

And what did you do, replace the Left bear with it's original OEM, or did you do the RH bearing mode?

[Fudd]

I hate it when someone asks for help with a  problem and then doesn’t post the resolution to the problem.  I’ve been guilty of this so I wanted to remedy this.  My clunking/grinding in the rear end  turned out to be the left rear bearing. I couldn’t get it to test bad until I drove out the bearings, so I replaced both rear wheel bearing to be safe. Everything is good now.

Glad to see some resolution to the problem.  I've been hearing the slightest grinding sound coming from the rear of my bike.  I'm about due to pull the wheel anyway to service the rear end.  I already have rear bearings on hand, and it's my plan to replace them at that time.  A post last week was frightning, showing totally trashed drive gears (still with grease on them.)  I want to think that a wheel bearing failure led to the destruction of the rear end.

[Ricky-D]

I think there was a whole lot more that a "bad bearing" involved in that rear end.

Mainly, it was neglect that caused that catastrophe.

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