[Udi]

I've never had much luck with headsets staying tight, and this is my latest dilemma. I'm running 760mm bars with a direct mount stem on a boxxer, through an e13 reducer / FSA IS2 headset. Running a starnut and alloy topcap, no spacers.

The DM stem means that the only things holding the crown down (and headset tight) are the 3 topcrown bolts. I've switched the three bolts to 12.9 grade steel (stock is 8.8) and torque them down pretty hard.

I do everything up nice and tight and it's sweet, but every ride it comes loose, and when I'm messing around on the street I can feel and hear some upwards pulling. I'm sure it has something to do with the leverage of the bars when muscling the frontend around.

Anyway, has anyone else had this issue and managed to solve it? I saw someone mention it a couple of days ago. I'd rather not have to run a headlock.

 

[Transcend]

Haven't had the problem, but was going to recommend a headlock before I got to the last sentence. Do you at least have a top cap with spacers under it and a star nut? Not super tight or anything, but it may help a little and keep things from rocking?

 

[Udi]

Yeah I'm running a topcap and starnut, no spacers but the steerer takes up the full height of the topcrown with *just* enough space to tighten it down (it tightens fine), so I don't think there are any crown-steerer surface area issues either.

 

[Kanye West]

If you are torque-ing your bolts to yield, they should be replaced every time you remove them. It takes a lot to do this, BUT I still see people doing it with stem bolts and running into the same loosening problems - basically being hamfisted without knowing it.

 

[DirtMcGirk]

I was doing this every run with my King headset.

Gotta be honest, I got their headlock, and have never looked back.

Now its nice and tight, no more BS play, and I got to keep my gay ass pink headset.

 

[Transcend]

King headsets last for ages ( I have one going on 6 bikes now), but they loosen up like crazy on a DH bike as they don't have a wedge type piece at the top, just the rubber gasket.

 

[ska todd]

I was doing this every run with my King headset.

Well, that's more b/c of the lack of compression ring than anything else...

-ska todd

 

[DirtMcGirk]

The no compression ring issue was a pain in the ass. King isn't really made for the world of DH, but its so damn pretty.

I like the king head lock as I don't have to worry about pulling out the star nut. Its a beautiful piece of billet work, and really does the job quite well.

 

[ska todd]

King isn't really made for the world of DH, but its so damn pretty.

It's also a lot of fun for customer service guys when they get calls about ovalized headtubes on DH frames. Then you have to explain why not keeping their pretty $150 headset tight or just running a $25 one would have prevented it. Ranting and expletives generally ensue.

-ska todd

 

[BigHitComp04]

Running my stock Cane Creek headset in the Demo 8 with Dirty 30s and a direct mount stem. Only have to tighten it up every once in a while.

 

[buildyourown]

I've got Gravity wide bars and I'm using a direct mount stem. Zero issues. Just a couple of 4mm stainless bolts holding things tight.

You might need a spacer under your top cap. You may think you are getting things tight at first, but really bottoming out on the top cap. It may feel tight, but once the wedge settles in, things loosen up. Throw a 3mm spacer under there for a day. It won't cost you anything. If that still doesn't work, I would replace the wedge with a new one. Still only a $3 fix.

 

[Udi]

Hacktastic - I'm pretty sure that tightening 12.9 grade bolts to yield would first result in a stripped out crown. The bolts are fine, and I replaced the stock ones with better ones - nothing changed.

BYO - I've already tried replacing the wedge and crown race with no improvement. I'm fairly sure the topcap isn't bottoming out on the steerer or starnut but I'll try a spacer anyway because I'm out of ideas for now.

Does anyone have any other ideas?

 

[davep]

I am running essentially the same set-up (boxxer, e-13/IS headset, DM stem, 750 bars....) with zero loosening over this last season...so I dont have any personal experience with this exact problem to share...

But,
I would pull everything apart and clean every contact surface with some acetone just to make sure they are clean of grease. Then smear a thin film of green (press fit assembly) loctite on the top crown contact surfaces. You could even do the compression ring/steer tube interface.

Any chance your lower crown is creaping down (stanchions being pulled through), rather than the upper one up?

I know you are weight concious, but you can fab up a pretty light headlock with two topcaps, two ti bolts and a hollow aluminum tube cut to length(internally thread with a tap).

I know you know this, but just for the observers.....cranking down on pinch bolts can stretch the aluminum being pinched and result in a permantly loose fitting. I have seen a handful of stems that have done this...

 

[P.T.W]

Mabe you could try not being such a brute????
kidding
Ummmm have you thought about trying a locking agent from loctite..such as studlock(i forget the number)or something simmilar. Iv'e used this on a stubborn stem to stop it spinning

Doh dave bet me to it while i was trying to find the number....oh the loctite website is arse!!!

 

[Udi]

I've tried cleaning everything with spirits and running green loctite (bearing retaining compound + left to cure) with no success. My lower crown is done up quite tight, I know for sure it's tighter than the top one thanks to the two bolts per side. So it's definitely the top one moving up rather than the bottom one moving down.

I have a fairly light headlock (unfortunately don't have the resources to make one like you said, otherwise I would)... but I've got a gut feeling that I'd have the same results even with it in. I'm not going to try it until I've tried everything else though, because I'd have to rough the starnut out.

Out of interest - are you running the headlock atm or just a starnut?

 

[davep]

Out of interest - are you running the headlock atm or just a starnut?

Honestly I dont remember. It is winter here (week of snow, then a week of torrential rains = major flooding, houses washing away, largest freeway closed, etc) so the bike is 'relaxing' for a bit.....let me go check.



Back from the garage.....
I was thinking it was just a star nut, but it has a cut/chopped/minimized woodman headlock. This: http://www.sicklines.com/gallery/showphoto.php/photo/3961 with the bottom plug shortened and drilled out and a lighter top cap with a ti bolt. I woud guess it is half of the original weight.

The home made model is simply a 5mm ID aluminum tube from the local hardware store that was cut to length and hand threaded with a 6mm tap. It is keeping the King from constantly loosening on the trail bike.

 

[toodles]

udi - dumb question but I'll ask - Have you tried other crowns?

How far through the top crown does the steerer go? If you cut your steerer with a pipe cutter instead of a hacksaw, it tends to "pinch" the metal providing a smaller O.D. than a standard steerer.

 

[Sverre]

I´ve used King headsets for years with nothing but trouble. Constantly coming loose and lots of creaking. Swapped it for a cheap headset with a compression ring and it didn´t need thigthening once all last season. Love it!

 

[MrPlow]

What Toods said, try another crown, maybe that one is damaged, could be loose threads from your excessive bolt tightening even??

 

[dilzy]

You know UDI, I'm beginning to see a pattern. You strip Maxles left right and centre and then need grade 12 HT bolts to satisfy your naquadria powered urge for clamping fury. EDIT It was socket ruining the maxles, not you. sorry.

Maybe, just maybe, your over tightening things a little, which has damaged your crown; ovalised your steerer ect and is giving you the grief.

 

[buckoW]

I have had the same problem 3 times over the last 8 years. One boxxer and 2 40's. I tried everything like you are doing but the solution was new crowns for me. Twice it was the top crown and once it was top and bottom. I had solved the problem for short periods of time by lightly sanding the insides of the top crown where it touches the stanchions. It seems like once it starts it is hard to stop it without replacing the top crown.

Are there any markings on the stanchion tubes? Is there any residue on the insides of the crowns? Are there any markings on the steerer tube where the upper race sits? I had that problem all summer long until I got a new top crown. Good luck with that it was driving me crazy this last time.

 

[pyynö]

Crown pinching on topcap edge? Needs to be a deep "edge" though to be an issue. Broken headset?
Thinking out loud...

 

[Jonny5]

There is some sort of upward toque or flex on the top crown on a boxxer. I had a carbon top cap with alloy bolt come flying at my face when it snapped a while back. Haven't had an issue since with a ti bolt. Like pyyno said some top caps have a pretty close lip, perhaps that is bottoming before it can grip the steerer?

 

[kidwithbike]

for those of you with problems with your King check out this modification, Basically you use a Sealed pig Wedge that you file down a bit...

As for Udi's issue, i have run 29.8" bars, DM, a starnut and the same headset setup as you for a very long long time nearly 2 seasons? with no loosening. I am thinking it maybe be a lack of spacers or your upper crown is stretched and pinching...

 

[Cant Climb]

I am thinking it maybe be a lack of spacers or
your upper crown is stretched and pinching...

Yup.....something is not flush. Maybe put in a tiny spacer....

Been running CK for 10 years. One on my trail bike one on my DH bike. Thousands of runs........thousands of hours on the trail.

Never one issue.
No creaking.
No loosening.
Both are still smooth as glass.

 

[rollertoaster]

If all else fails, try some valve grinding compound on the surface where your crowns contact your uppper stanctions/steerer tube. The increased friction should hold it, sounds like your upper crown is stretched out.

 

[demo 9]

I know you know this, but just for the observers.....cranking down on pinch bolts can stretch the aluminum being pinched and result in a permantly loose fitting. I have seen a handful of stems that have done this...

Could this be the reason my shop said that my stock crowns "stretched" and it isnt my chris king headset causing the problem? stock bolts tightened as much as i could with hand allen key 6 inches long

 

[boogenman]

headlock seems to be the most economical option.

I have a Sunline reducer headset on my bike with the same setup, never had one issue with it being loose all summer. That headset rocks if you install it correctly.

 

[kidwithbike]

my stock crowns "stretched" and it isnt my chris king headset causing the problem? stock bolts tightened as much as i could with hand allen key 6 inches long

on some crowns the tolerances between the stanchions/steerer and the bore of the triple clamps arent tight enough...if you overtighten the clamps it is quite likely you will stretch the Aluminum just enough to loose clamping force... if you are really ghetto/desperate you could put a very thin shim in there... i recommend a PBR can. haha nah thats likely too thick, The clamp will continue to stretch though! and over time it will become untrustworthy.

 

[dhrookie]

why not run a King steelset?

 

[Jm_]

why not run a King steelset?

?? Cause it's designed exactly like the aluminum one and will also loosen?

 

[toodles]

why not run a King steelset?

A) Because King headsets suck balls.
B) Because the headset is not likely the cause

 

[Udi]

Thanks for the suggestions guys. I do have other crowns so I'm happy to try that out, but honestly - I've had this issue since the fork and crown-set were new... with stock bolts, done up gently. So I'm fairly sure a stretched crown wasn't the cause for this issue. Topcap isn't getting pinched by the crown.

Jonny - That's good to hear, I just wanted to know that I wasn't the only one seeing how much the top crown gets pulled on. I've got a feeling that my starnut or bolt are getting pulled upwards and maybe a more durable setup would help keep the crown down.

BuckoW - No marking that I can see on stanchions or crowns. There is some marking on the steerer tube where the upper race sits. It would be a pain to replace the lower crown/steerer for that though.

Toodles - Steerer was cut with a hacksaw (old crown for cutting guide) and filed / sanded from coarse to wet and dry so it's neat. I wanted it pretty for running no starnut/cap, obviously I am now though. Steerer goes 95-98% of the way through the crown... I'm going to try a thin spacer or two, but I'm kinda doubting that's the issue as it tightens up pretty nicely before I ride. How much can things "settle in"...

You know UDI, I'm beginning to see a pattern.

Thanks genius, but I can work on a bike - which is the reason I HAVEN'T had an issue with a maxle, EVER (unlike a myriad of others). Please don't misquote. I upgraded the bolts originally because rockshox uses lower grade bolts compared to other manufacturers (marzocchi uses 12.9 for the same 5mm bolts) and I wanted to make sure the bolts weren't responsible for the loosening. I've seen them slightly bent when removed from factory installations, they're soft.

 

[buckoW]

BuckoW - No marking that I can see on stanchions or crowns. There is some marking on the steerer tube where the upper race sits. It would be a pain to replace the lower crown/steerer for that though.

Keep an eye on the steerer wear. It might be the issue. Is it on the backside of the steerer?

 

[DirtyMike]

Two things I can think of right off hand, First....No sapcer under the top cap, as many others have said.

Second is overtightening has sterachted teh crowns so the "Split" is actually touching when you tighten in up, causing it to feel tight, but not actually feel tight. I have seen that moe than a few times with stems themselves.


Other than that, I cant think of anything else without having it in front of me, Its not a King headset problem, your not running a King.

I am not fond of headlocks, seen too many of them overtightened and making the head sets were out too fast.

Try a spacer, Try a torque wrench.

 

[MrPlow]

why not run a King steelset?

How the heck would that help? and it would be too high for Udi..

 

[daisycutter]

there is no way you ovalize your head tube with a steel headset, Hell just getting one in my head tube took alot of work. if I ever take it out I hear you need to cut it out. the loose headset issue how ever would not be improved it just would not damage your head tube

 

[Mr Nug]

Slight change on a theme but do you have a spacer between the headset and the top crown? The surface area under a boxxer crown isn't that wide and reduced 1.5 headtube has quite a big footprint.

I don't have my boxxers anymore but I remember running a 2mm spacer under my upper crown as edge of the headset was just touching the edge of the crown leaving a slight gap. Means it tightened up nicely on the stand but as soon as you rode it down the road it'd loosen off.

Failing that you could inspect the steerer for "starnut creep" and maybe switch it out for a new one. I've had a few starnuts fail (after a few years of use) just because the flanges were fatiguing under the constant load.

 

[bullcrew]

Wipe the steer tube down with alchohol. Mine was doing this off a bigger jump everytime. Chris said wipe the steer tube down and turns out there was contaminate on it causing the stem to slide a bit. I was getting 1/8th of lift and pulling the star nt out of the steer tube.

 

[pyynö]

There is some sort of upward toque or flex on the top crown on a boxxer. I had a carbon top cap with alloy bolt come flying at my face when it snapped a while back. Haven't had an issue since with a ti bolt. Like pyyno said some top caps have a pretty close lip, perhaps that is bottoming before it can grip the steerer?

Didn't mean topcap-stearertube contact. What I ment was the crown itself pinching the topcap when tightened and thus not properly clamping the stearertube itself.

try some valve grinding compound on the surface where your crowns contact your uppper stanctions/steerer tube. The increased friction should hold it,

kinda like "carbon-grease" Sweet!
http://www.tacx.com/producten.php?language=EN&lvlMain=18&lvlSub=66&ttop=Carbon%20assembly%20compound