Unusual clunk

[BribieDuc]

Riding to work today, and I heard a few clunks coming from below, probably from the rear - a little hard to tell.
Happened at low speed.  Also noticed when at the lights the bike would only roll backwards a foot or so before it locked up...in neutral and with clutch in.  Moved freely forwards. Clunk sounds happened again shortly afterwards and bike now rolls freely backwards. Suspect I also heard similar sounds yesterday. Had a quick look on arrival at work, thinking something might be loose but couldn't see or feel anything.

Anyone have this happen before or have thoughts on the cause. I'm thinking something might be coming loose and swinging into the wheel  ... brakes seem fine, chain's okay, engine is running fine...gearbox (although the clunking sounds external) maybe? Bike has a few miles on it but its well maintained.

Thanks for any advice.

John

[dragonworld.]

Hmmmm, take your sprocket cover off and make sure that the cog is securely attached. If it was loose it could move along the shaft and bind on the chain?? Maybe??   

As you say, get the back wheel off the deck and rotate your wheel!   

I would think that if something is jamming internally, it would be locked up! Not coming and going! Peculiar??

[Betty]

You could also post on the Tech Board to cast a wider net.

[ace70]

had a friend with an SS that had something similar.
The retaining pin that holds the rear brake pads in had gone walking, and the pads where only held in by wear on the disks.
Very lucky boy that the pads didn't slip down and become lodged in between the disk retaining bolts 

Have a good look all around the rear end..

Good luck

[heatherp]

Check your wheel bearings.  I had one collapse causing partial lock up that would of been total lock up if I had kept riding.   

[BribieDuc]

Thanks for all the inputs (Tech and Oz Monster). 

Last night I put her up and checked all the suggestions:

Chain - a minor tight spot, RK racing X-chain
Sprockets - not too bad
Wheel Bearing - no lateral movement
Brakes - all there, tight, well off the wear line.

Found no problems...so simply re-tensioned everything and gave all an extra good lube. Will replace the wheel bearing at the next service (front was done at 75K, now at 98K).

300 kms on and no re-occurrence...although I'm listening   

Now, back to replacing the tail light on the Monza so I'm ready for the NDR... pretty unreasonable for a forty-four year old ducati part to fracture 

Again, THANKS 

[BribieDuc]

Hi, If you see my rear bearing thread, you will see the issue has been identified  and I'm having a good go with fixing it myself. heatherp  got me thinking that I should simply discount wheel bearings  through replacement and on that path I discovered a collapsed sprocket carrier bearing (I didn't even know they had them - next page in the manual - duh!)  - Thanks! That bearing was the noise I suppose when the bearing tightened and was forced round...also explains it not rolling backwards until this congestion cleared...
Thanks - the pointers solved what could have been disasterous for me and with the other responses to my other posts encouraged me to expand my own mechanic horizons a little further.
 
John

[dragonworld.]

Check your wheel bearings.  I had one collapse causing partial lock up that would of been total lock up if I had kept riding.   

Hey John, hey many K's have you done??

Checking, replacing all wheel and sprocket carrier bearings would seem to be a mandatory operation with the number of failures popping up here. 

My front wheel failure and found all the rest were on the way. Under 40,000k

Heathers rear wheel. And now yours. Shitty bearings being used from factory?? Maybe!! 

I think the lesson here is, check them all and replace them with good quality bearings, dont wait for them to fail, the result could be expensive and potentially catastrophic for you the rider. 

[heatherp]

Glad you found it before $$$ or hurtful damage to you or bike.   

Mine had only done 30k so now I feel justified being paranoid about bearings.  Dealt with a mechanic yesterday about fitting new (2nd hand) front wheel to mine.  He was a bit surprised about my specific demands (for bearings Spider - nothing else!!!).  But thankfully he took me seriously.

Maybe we need one of those maintenance clips on checking all these bearings on the bike periodically.  I know it would benefit me.

Hey John start filming what you are doing (to the bike Spider - nothing else!!!)     (gawd I have to be so careful about what I say)

[BribieDuc]

I can't complain about mileage...

Brought my baby in 2002. By 2005 she had 20,000k.
Today she has 98,500k - primarily to a rather decent commute to work.

Other than routine consumerables, it's been bearings (which I'm going to treat as a 50,000k replacement item from now on even with SKFs), a gear lever return spring and a rusted from the inside out tank (at 65,000k).

[heatherp]

Just normal wear and tear then.  I reckon I just got a Friday job (bearing wise) either that or riding in the rain too much.  Just sooo thankful that I stopped riding when I did.

[dragonworld.]

Just normal wear and tear then.  I reckon I just got a Friday job (bearing wise) either that or riding in the rain too much.  Just sooo thankful that I stopped riding when I did.

As I found out from the Bearing service there are SKF bearings and then there are real SKF bearings!! The ones that came out of my bike were the low budget types. Apparently the give away is the crappy looking SKF engraving on the bearing. (Looks like a home done job!!  ) as to the crisp indented letters. 

Apparently along with most businesses nowadays , the bearing companies are also outsourcing some of their work along the err, umm "cheaper" manufacturing routes! 

You gotta request the "Good" stuff, or you are likely to get the budget quality.