Assphalt

Hey guys,

since I purchased this nice new frameset (self built) 4 months ago from bike shop about 70 miles away, I have been having some headset loosening issues, mostly because of insufficient torque and poor stem. Anyway, bought 3T stem and headset (integrated, carbon frame) isnt loosening anymore, yet I still (it was always there more or less) have an issue with headset cover (NOT preload cap) slight forward movement when I hardly press front brake (rim brake) sit on the top tube and try to move the frame strongly forward and back. I can feel it when putting my finger over the headtube/headset cover gap. We are talking 0,1s of mm, small but sensible. Also the bars arent rotating as free as other bikes, not causing an issue just sensible when you let them swing from side to side when holding bike in the air. Im super anxious about this since the primal headset loosening issue has left cosmetic marks on bearing surfaces in the frame and on the fork, just cosmetic, not worn, cant include pictures because of local newbie policy.

Thanks for any opinions.

Edit: everything is greased, only clean area is on stem on steerer interface

FBinNY 

Given that you have a tight (steering drag) and loose (fork movement) headset at the same time, I suspect headset is not assembled correctly.

Possibly the bearings are not placed correctly, ie.one is either upside down or upper and lower are reversed. Or it wants a spacer below the top cap.

Take apart and reassemble double checking each step.

Assphalt

Thank you. Im pretty sure I placed everything I received in the package accordingly, will check the clearance on dust cover/headtube.

If bearing seats in carbon frame are bad, misaligned, either from headset loose or ever since I bought the frameset, is there any way to re- face them? Is it a job a LBS would do? Im talking tapered seats.

Assphalt

Photos:

FBinNY 

I wouldn't worry about the frame or fork. That's almost surely not the problem. If it were it couldn't be fixed easily anyway.

Look for something touching or rubbing and keeping the bearing stack n from compressing.

It's possible that the frames top bearing pocket is too deep, so the top cap touches. If so, an added spacer will solve it.

Just be a detective and use your eyes and hands and you should be able to resolve this.

tFUnK

I second the spacer suggestion. Had a similar issue on a Specialized Tricross and a spacer or two solved it for me. The spacer goes between the headset cover and the wedge that compresses down on the top bearings. I bought a multi-pack of thin spacers and needed two to fully resolve my issue.

Assphalt

Will look into it, thanks. Pic:
(there is a rubber lip seal visible)

Assphalt

Little update and a new question:
headset has no play (same setup) when testing with front brake locked and pulling bike back and forth heavily but I can hear some "grease mashing noise" during the test. Also when droping the bike from height on front wheel the headset vibrates a little bit (other bike doesnt vibrate or definitely less) and makes that grease noise. Is there a need for a new hs bearing though it felt ok in hand? Could it be damaged from the previous loose setup in terms of causing this vibration?

Again, no play through "brake lock- push a bike with body "test.

FBinNY 

It's possible that a very slight increase in preload might eliminate that last vestigial bit of play. However I'd apply the Goldilocks rule and ignore it.

FYI the Goldilocks rule is, If you're sure there's play, it's too loose. If you're 100% positive there's no play, it might be too tight. If you're not sure either way,that's just right.

You've been obsessingover this f or too long, it's time to ride the bike.

oldbobcat

Or possibly somebody forgot to install the split wedge washer that keeps the top of the steerer centered in the top of the headtube. Something is moving in there and it shouldn't be to difficult to carefully dismantle it to find the culprit.

FBinNY 

We're well past that. Read what followed the quoted passage.

choddo

A linguistic aside: I’m assuming you’re not a native English speaker. “sensible” in English doesn’t mean something that can be sensed or felt. It means something that makes logical sense (a sensible idea or sensible clothing for the weather, for example). We actually don’t have a single word for it. Closest is probably “tactile” but that’s a bit different, used more for positive sensations like “GRX shifters are quite tactile”, so most people would resort to “it can be felt”. You have to love English.

Ref the headset, I have one on my gravel bike which seems less perfect than you describe in that last post and it rides absolutely fine. Do you still have the steering tightness?

Assphalt

Good to know, I ordered new hs bearings anyway, unbranded are pretty cheap, will see if it improves.

Its still stiff, but only if you let the bars swing from side to side, completely ok for turning. But thats almost surely caused by the seal pressing against the frame, but since 0,5 mm washer didnt help, i suppose some seal friction is inevitable.

Crankycrank

Don't forget to take into account that the brake/shift cables create some resistance the further you turn the bars.