Dangerous sounding rattle

[Joe]

I was just having a fettle and noticed that the headset had come slightly loose (slight knocking when rocking the bike on the front brake). I tightened it up and eliminated the knocking but noticed a really dangerous sounding rattle. It happens if I tap on the bars, or bounce the front wheel on the ground whilst holding the top tube. I can't pinpoint where it's coming from exactly but it sounds dangerous! Needs sorting pronto as I'm down to this bike only at the moment
Any ideas? I'm thinking maybe the headset bearings are shot?

 

[Crackle]

How longs the headset been loose? I completely hammered a set of headset bearings within 10 miles when my headset became 'really' loose on a ride.

 

[02GF74]

you don't realistically expect someone to tell you whatt he casue is from that desciption?

it cold be anything from a cracket frame that is flexing or a ball bearing loose in the frame or a plethora of other things, some of whcih I cannot even begin to imagine.

I would suggest listening harder to licate the noise then to start removing parts and repeating test . ie. remove front wheel, remove bar, remove stem, remove forks etc. until you are left with just the pedal.

 

[Dave5N]

Probably headset. Have a look there first.

 

[Joe]

Cheers all. I think I've narrowed it down to the front hub but I can't seem to figure out how to adjust it These are my first Campag wheels (Khamsin's) and they don't have the same setup as my Shimano's. There are no locknuts and I'm a bit stuck, is there a guide online somewhere?

 

[softpeadals]

.
As far as I am aware the Khamsins have sealed bearings.
Could it be a loose spoke or a broken spring in the QR lever?

 

[Joe]

Well the wheel is (very slightly) out of true, so maybe? Quick release lever appears fine.
If you hold the fork with one hand and move the wheel from side to side with the other there is a bit of play (not present on the back wheel), which I believe is the cause of the rattling...

 

[softpeadals]

Does the wheel make the same rattling sound when it's off the bike and you bounce it on the ground?
If it does then it sounds like the hub.I'm not familiar with those hubs so can't help you on that one.

PS
Is your computer sensor tight up on the spokes

 

[fossyant]

If you have a bit of play, you should be able to adjust the 'loading' on the cassette bearings - Mavic have been using these for years, rather than cup and cone. I'm not familiar with campag hubs, but you should be able to adjust the loading (like with cup and cone) - anyone with campag hubs on here.

Mavic's are fairly simple to do, undo locking nut and tighten the inner nut, then tighten the outer one again. - Mavic use a 'pre-load' washer - what ever it is .....

 

[Joe]

I'm pretty sure it's the hub. Whilst I can't recreate the exact sound by bouncing the wheel on the ground, there is no rattling from the front end when the wheel is out of the forks.
This is what the hub looks like (apologies for the crap picture....and dirty bike!).

How do I go about adjusting it, presuming I can? Like I said, this is my first bike not to have the standard shimano cup and cone hubs.

 

[Aperitif]

I have these wheels on my commuter Joe - I just took one off for a look. (Mine are clean )
As softpedals says, the bearings are sealed / non adjustable it seems - mine run true and without any noise.
As Dave says, headset noise is a more likely cause. I have suffered.
Put another wheel in your bike and see what happens...
You might also try and put oil at the points where the spokes pass through the hub - you never know.
Remove stuff from your bike - maybe start with the computor sensor and conduct an elimination 'test'.

 

[Joe]

Cheers. I've switched wheels and the sound goes away, so I'm sure it's the hub. What now, are they literally non adjustable? Meaning I need a new wheel?? I've only had them for a few months!

 

[softpeadals]

I think you should take the wheel back to where you bought it Joe and ask for a replacement,or at least a rebuild on a new hub.
I'm pretty sure it's a sealed unit and if you start trying to fix it yourself you might invalidate the warranty.
A quick Google indicates you are not alone with this problem which in turn would suggest Campagnolo will be aware of the issue so you shouldn't have too much of a battle getting a replacement.

 

[Joe]

Yeh I think I may have to. I bought it online though so it may be some hassle (and postage!).
Can you link me to what you found (or just tell me what you searched for) as my google skills have turned up nothing

 

[softpeadals]

Trying to remember what I Googled and came across this.
http://forums.roadbikereview.com/showthread.php?t=123858

which led to this;


OK FYI.

There are two circlips with no holes or anything to grab them, but I managed to get them out using a pair of compasses and a tiny screwdriver - very fiddly though. Once these were off the dust caps pull off.

The circlips provide no structural contribution to the wheel and only serve to keep the dust caps in place. Without them the dust caps are pretty secure anyway due to a rubber seal on the inside, and of course once the wheel is on the force of the QR keeps everything tightly together.

So I suggest if others want to service their Khamsins you get the circlips off and leave them off - that's what I'll be doing - save you the hassle next time.




Perhaps not all is lost.