My King headset keeps coming loose...Any

[goblue]

one else have this problem. Literally after only a thousand miles on my new Legend SE it's come loose 3 times! What's up with this??

[BumbleBeeDave]

. . . by "coming loose?" Do you mean there's play in it or literally it's coming loose from the frame? Carbon steerer with expander or aluminum steerer with star nut? I've had my CK on my Legend since I got it in 2001 and never had any problem with the actual CK headset. The star nut was pulling out, but folks at Serotta said that's because the steerer on my F1 fork is Titanium and the metal is too hard for the star nut to grip good. I put in a second star nut and all is fine. It probably adds half an ounce to the bike weight, but what the hey . . .

BBD

[weaponsgrade]

If you have one of those expander plugs for a carbon steerer, check to make sure that the expander plug is still expanded or wedged in the steerer tube. The top cap can be tight, but if the expander plug is loose then it'll result in the headset loosening up.

[Ripple]

one else have this problem. Literally after only a thousand miles on my new Legend SE it's come loose 3 times! What's up with this??

I have been having the exact same problem with my 08 Legend. Mine "came loose" 3 or 4 times since June. (play with the steerer tube) Each time I popped the cap or brought it into the LBS, the expander plug had backed its way out.

So I am very curious to hear what others have to say.

Ripple

[mickc]

I've recently come across this issue too, albeit on a mountain bike.

I put a new fork (Manitou) and the headset felt like it would not stay adjusted after even a brief ride and would creak if I over-tightened. I've tried everything: new star-nut, re-seated the headset and fork race, over-tightening, ignoring. It didn't do it before (w/ White Bros fork) so I thought it must be user error on install of new fork (me)

But: it seems that if the fork steerer is not bang on in diameter the o-ring on the King headset allow too much play that feels like it's not seated once settled. I changed the headset to another make (Acros) with a compression ring and all is good.

Now, I wouldn't expect this to happen on decent road fork as the diameter should be good and the forces at work less due to shorter fork length than on a mountain bike.

Is the fork steerer extruded alloy? - then like my Manitou fork it could be under-sized (unlikely as I think I was unlucky here). Else, are the stem bolts fully torqued to spec? It is these that hold the headset in adjustment (not the top cap compression bolt)

[David Kirk]

Make sure both the expanding dealio inside the steerer has a coating of the special carbon gritty grease and the inside of the stem has it too and your stem creeping up the steerer deal will be history.

dave

[fjaws]

Steerer tube 5mm below top of stem when tightened?? Seen countless bikes with steerer cut to long and they loosen. Throw in an extra spacer and the problem goes away. As stated above, once adjusted properly the stem bolts should hold it tight not the top cap bolt.

[Elefantino]

Make sure both the expanding dealio inside the steerer has a coating of the special carbon gritty grease and the inside of the stem has it too and your stem creeping up the steerer deal will be history.
I love it when our forum experts talk technical. :D

[soulspinner]

Steerer tube 5mm below top of stem when tightened?? Seen countless bikes with steerer cut to long and they loosen. Throw in an extra spacer and the problem goes away. As stated above, once adjusted properly the stem bolts should hold it tight not the top cap bolt.

Seen this on my own rig... :crap:

[Ti Designs]

Let me guess, it's the Reynolds expander with their large aluminum top plug???

Let's put names to the individual parts to avoid confusion first.

1) the plug - that's the round aluminum clinder with the rubber O-ring around it.

2) the expander - the cone shaped thing that expands the plug. it also has a large external threaded section at the top

3) the binder bolt - the steel bolt with the 5mm allen head that pulls the expander into the plug

4) the cap - this is what you see from the top, it turns with a 6mm allen wrench and has a female thread to match the large male thread on the expander.


Problem: the large threaded interface between the expander and the cap has far too much play and pulling on the bars is walking the cap off the expander.

Solution: I own a lathe and have way too much time on my hands. You may want to try using the UL plug instead. Just a word of warning, the cap was designed to be an internal reinforcement on the carbon steerer. Putting a star nut in there isn't such a good idea if you don't have dental insurance.

[jellis]

Anyone know the proper torque spec as called out by Chris King?

[Ripple]

In my case: my rig is a legend w/ F3 fork with chis king headset.

I recently had a spacer removed and had the steerer tube trimmed. I will keep an eye on it over the next 100-200 miles to see if it remains tight. After reading the posts above, perhaps my steerer tube was a bit too long. And perhaps the recent trimming will take care of it. (In August, after a headset tightening, mine came loose after only 200 miles....)

GoBlue - Let me know how you progress addressing your issue.


Thanks all, :beer:

Ripple

[palincss]

Steerer tube 5mm below top of stem when tightened?? Seen countless bikes with steerer cut to long and they loosen. Throw in an extra spacer and the problem goes away. As stated above, once adjusted properly the stem bolts should hold it tight not the top cap bolt.

If it's the stem bolts rather than the top cap bolt that hold the tension, why should an extra spacer above the stem be necessary? What does it do? Or have I misunderstood, and you mean put an extra spacer under the stem?

[soulspinner]

Let me guess, it's the Reynolds expander with their large aluminum top plug???

Let's put names to the individual parts to avoid confusion first.

1) the plug - that's the round aluminum clinder with the rubber O-ring around it.

2) the expander - the cone shaped thing that expands the plug. it also has a large external threaded section at the top

3) the binder bolt - the steel bolt with the 5mm allen head that pulls the expander into the plug

4) the cap - this is what you see from the top, it turns with a 6mm allen wrench and has a female thread to match the large male thread on the expander.


Problem: the large threaded interface between the expander and the cap has far too much play and pulling on the bars is walking the cap off the expander.

Solution: I own a lathe and have way too much time on my hands. You may want to try using the UL plug instead. Just a word of warning, the cap was designed to be an internal reinforcement on the carbon steerer. Putting a star nut in there isn't such a good idea if you don't have dental insurance.


You guessed it in my case..I just figured it was because of my FSA heaset

[Birddog]

If it's the stem bolts rather than the top cap bolt that hold the tension, why should an extra spacer above the stem be necessary? What does it do? Or have I misunderstood, and you mean put an extra spacer under the stem?
It doesn't matter where the spacer is located, the purpose is to gain the 5mm distance needed between the bottom of the top cap and the top of the steerer tube.

Birddog

[Ti Designs]

You guessed it in my case..I just figured it was because of my FSA heaset


I've seen it with all sorts of headsets including my own King. You can take the whole thing out without taking off the cap (so the rest of it doesn't slide down the steerer) with a 5mm allen wrench. You're going to the steel bolt in the expander, not the cap (which uses a 6mm), back it off a couple of turns and you should be able to lift the whole expander out with the cap. With the whole thing in your hand, check how much play there is between the cap and expander. Most of them I've seen will wiggle about 1/2mm side to side. If your internal reinforcement is walking that much, no amount of tightening the bolts is going to help.

[Satellite]

It doesn't matter where the spacer is located, the purpose is to gain the 5mm distance needed between the bottom of the top cap and the top of the steerer tube.

Birddog
It does matter putting the spacer on the top will NOT change your handle bar drop. Putting it under the stem with raise your bars by the equivalent amount. Granted 5mm is not a lot but it will raise your bars.

I didn't know this but most stem manufactures recommend the 5mm top spacer for a secure interface stem to steer tube. I have always cut my steer tubes flush with enough space to properly tighten the top cap.

I agree the problem is most likely too much steer tube for the top cap to obtain the proper torque specs tighten approx. 4-10 in.-lb. (Max.15 in. lb.). The other cause as mentioned expander nut is not holding in the case of a road bike.

The top cap is only to achieve proper torque specs the stem actually does the work of maintaining the torque (as someone else already pointed out). Once the top cap is set and the stem tightened you could remove the top cap but you don’t want to it would be a dirt magnet.

My mountain bike recently had a loose head set feel to it (also King), it wasn't the head set it was the Fox Fork seals allowing movement felt just like a loose headset. It took me a while to figure it out, now the fork is sent to PUSH for a re-work they custom mill the slider washers to the exact measured size, pretty cool. Pretty common with Fox Suspension Forks to have loose seals but that is why they are buttery smooth from the factory. My fork is just too buttery.

Satellite

[fjaws]

I think his point was that from a mechanical standpoint, above or below does not matter so long as the 5mm clearance is obtained. So if one isn't ready to start cutting on the steerer or just wants to test the theory before cutting for a permanent fix, they could simply add a spacer. I would think it's a foregone conclusion that if the spacer is put under the stem it will raise the handlebar.

[dvs cycles]

From the Reynold website:
How long should I cut my steerer tube on my Reynolds fork?

You should cut the steerer to the proper length to allow for the needed number of spacers below your stem, not to exceed max amount with a 5 mm spacer between compression plug cap and stem.
----------------------------------------------------------------------
What I've always done is to make sure there is enough space for the cap to preload the headset bearings without exceeding this. Most stems if you measure them 5mm would make the top clamping bolt uncomfortably close to the top of the steerer tube , if not above it, if you left this much space.
I shoot for 1 to 2 mm below the top of stem if I don't want to put a spacer on top. Sometimes just looks cleaner with a flush topcap.
The stem holds or is supposed to hold the adjustment. If it is slipping it is not the cap that is causing it. The cap is just for the adjustment.
Check the stem. :beer: