[quickKarl]

posted in orbeas forum, thought id more input here.
--------------------------------------------------------------------------------

have had my orca for 4mths now and love it. but ive been having a problem with keeping the torq for the head set, the expander down in the fork will creep up loosing the torq. and eventually the head set is loose. seems to only happen when rode over rough roads for an extended time, like brick roads. i've tried to torq the expander more the the torq for the headset, but eventually it loosens. ive cleaned the inside of the fork, the expander, even sanded the expander a small amount.
has anyone else had this problem and what have you done?
i've emailed orbea usa for suggestions and asked for a new expander but have not heard back yet..

thanks,
karl

 

[DIRT BOY]

What fork are you using? Is the steertube at least 1 cm below the stem or spacer on top?
If not get a micro spacer and put it below the top cap or cut the stem down 1mm.

 

[quickKarl]

expander

i put the expander 1cm below the cap, then torq the cap bolt to 10 nm the recm.from orbea. its an orbea carbon fork. after the riding on bumpy roads for awhile the expander has slipped up so there is on longer any preset torq on the bolt. the problem i believe is getting the expander to hold in place in the fork.

karl

 

[mtpisgah]

It's probably not the expander

Clean the steerer tube where the stem clamps and make sure you clamp the stem to the recommended torque. The only purpose the expander and top cap serve are to tighten the fork before you tighten the stem. After that, it is the stem's job to keep it tight.

 

[C-40]

another possibility...

As other noted, it's the stem's job to hold the headset adjustment, not the top cap. One problem that appears to be a constantly loosening headset is failure to properly preload the headset bearing in the first place. Integrated headsets can reuire quite a bit of top cap tension to preload the bearing (like 5-8Nm). I tighten mine until I feel a bit of extra drag as the for is turned, then loosen just a bit. If you hit a sharp bump in the road and hear a "thwack" sound, it's an indicator of loose bearings. If this hapens on the first ride, my bet is the top cap was never tight enough to start with.

As a last resort, you can always epoxy the expander into the stering tube permanently, if you're sure you won't want to move it.

 

[Mersault]

Clean the steerer tube where the stem clamps and make sure you clamp the stem to the recommended torque. The only purpose the expander and top cap serve are to tighten the fork before you tighten the stem. After that, it is the stem's job to keep it tight.

If after you do what was recommended above, and it still goes out of adjustmend, try some hairspray on the steerer. No kidding. I had the same issue with an aluminum steerer and stem. cleaned it, sanded it, torqued it, the problem came back. then I took some aqua net hairspray and put a shot of it on the steerer, let it set up for a few minutes, put the stem on, adjusted things up, and It's been fine ever since.

Search under hairspray around here, and you'll see. It's worth a try.

 

[quickKarl]

tight

i used a totq wench set for 11 nm the rec. spec. so it was tight enough, but the stem may not have been.
thanks for the suggestions. will reset all and torq stem.

karl

 

[flying]

One other thing is if you didn't cut the fork at least 2mm below the stem top. The cap could be bottoming out & not getting any preload at all.
As others have said the plug moving would have no bearing on it coming loose if it was set right first. Once the stem is tightened the plug could actually be removed as it is no longer doing anything. Some folks do in fact remove it to save weight ( not me ) & then use something like a Smolke A-head cap.
My bet is you are not getting proper preload to begin with. Also you said the top of the plig is 1 cm below the cap? Usually it is further down & the bolt is long enough to reach it.
Good Luck & be sure the cap is not bottoming out on the steerer tube.