Recently bought a used 2004-ish Bianchi ML3 aluminum frame with a Bianchi-branded carbon fork. After several steel frames with threaded headsets, this is my first foray into threadless territory, and it's got me stumped.

The proper procedure is to tighten the bolt on the headset to just the right tension, and thereafter to tighten your stem. Right?

The front end feels unwieldy, though, as if the headset is too tight. When riding in a straight line there are moments where the bike almost feels like it's starting to get away from under me, like the balance isn't symmetrical. Which, again, is a tell-tale sign of a headset that's too tight.

Thing is, I'm tightening the headset just to the point where there is no longer any play when you activate the front brake and try to rock the bike the bike back and forth, and once I tighten the stem the front fork seems to turn freely.

So what gives? Am I doing something wrong? Could it be a problem with a bearing in the headset? A problem with the fork? A problem with my position on the bike?

You may just be tightening too much. You just tighten the top bolt to get preload and then tighten stem bolts down. Have you watched any YouTube videos on the subject?

Probably tightening the top cap too tight. You need to tighten it so that it puts a little bit of preload

But I can't get it any looser. I set it just barely beyond the zero tension point where the bolt would be completely loose. When I try to ease back on the tension the front fork is too loose. I'm literally right on the edge between loose and tight.

A month ago I got a new mountain bike with a threadless headset, and it has a more gradual zone to work with where you can adjust the tightness. But my Bianchi ML3 road bike doesn't seem to have that gradual zone at all. This is why I'm wondering if there's a problem with the bearing in the headset.

If I understand your problem correctly, you need to use shims under your cone spacer. They will provide just enough clearance for the cone spacer edges when you tighten down the top cap so that the steerer still turns freely.

I use these on my bikes: FSA Microspacer, 1-1/8", .25mm

Oh? I'll have to look into that. I haven't taken the headset apart at all, so I don't know what's going on inside of it.

Edit: Just to clarify, by "cone spacer" do you mean the spacers below the stem?

There should be one larger, cone-shaped spacer underneath the others that matches the diameter of the head tube.

Maybe you should post a pic so we can be sure.

Edit: This pic is what I'm talking about (yours is probably like the shortest one in the front):


Underneath that spacer is a lip that pushes down on the steerer compression ring.

If the lip is too shallow, it won't compress the ring enough before the outer edge makes contact with your head tube – hence your problem.

You have to give it more clearance by putting just enough shims on top of the compression ring so that the outer edge of the spacer does not rub against the head tube after you've tightened the top cap.

Follow?

Here's a photo:

lubrication, some don't in fear of slippage after tight. If the headset has a rock in it when grabbing the front brake and trying to move it, it is too loose. If there is too much friction when trying to turn, it is too tight, or to dry. I was experimenting with certain torques, 5nm is overkill for the top bolt I probably did half of that. The tension on the top bolt doesn't matter at all when others are in place. If you wanted to, you could throw in a plastic bolt once you tightened the stem bolts.

Okay, I sort of get it. But this is a Bianchi-branded headset on a Bianchi bike. Wouldn't it be configured properly already?

Okay, I'll definitely try that.

Well, I don't know the context in which you're having the problem...

Did the bike come to you with the headset all wonky? If so, since it's a used bike, it's possible the PO mucked up the setup(?)

I think you should definitely post this in the mech forum. Much greater breadth of experience there.

Yes, it came to me like this. I bought the frame and fork from a guy who stripped the components off of it, and he bought the bike from an older gentlemen who bought it new. This suggests to me that the headset was never touched, and got me to wondering if maybe one or both of the bearings were worn. But I don't know.

I think I'll take it apart to see what it looks like, and maybe try the lube thing. If that doesn't work I'll consider getting a new headset.

Post pics when you get it apart.

Here's a diagram of a threadless headset to help you along:



And a link to some great info: Servicing Bicycle Headsets

I'll print that photo out and post it on the wall when I take the headset apart. Thanks!

roussseau, a new headset is so reasonably priced, even a very good one. Just replace the whole thing, and be done with it. I like the value in Cane Creek, even their cheapest ones are excellent, but the "40" series the definitely the sweet spot in the line. The only help you would need with this would be replacing the crown race. That is the only thing that requires tools that you may not have. I know this seems like a cop out, but sometimes new parts are just the most sensible fix, especially when they are not terribly pricey. The bike will look nicer too with a new headset. Don't fret that it won't say Bianchi. Stuff happens.

I'm happy to do that, and I do have some homemade jerry-rigged tools to remove the crown race (though I might not even bother), but this is assuming that it's the headset that's the problem.

Can one safely assume that it's the headset that's the problem here, you figure?

Two thoughts: 1) are the bearings shot? may just need to replace the cartridge bearings in the existing headset.

2) is the spacer on top extending out above the steerer tube? It should be about 1/8" above the steerer, so that you can tension the headset by tightening the top cap. if the spacer isn't above the top cap, the top cap will bottom on the steerer tube and not tension correctly.

as a last resort at a quick fix, you may be able to remove the "seal", as shown above and reassemble. it usually serves no function except as a very, very thin shim and cosmetic enhancement, and may be making contact with the headtube or outside race of the upper bearing, which could be causing the problem.

you may even find some other more obvious problem. for example, if the bearings are not cartridge bearings, one of the bearings may be installed upside down.

I didn't think about this last night, but from the pic of his bike, it looks like it has an integrated headset... which of course would make all this super-easy to check & service.

Anyone know for sure whether that's the case for this model of Bianchi?

I went to a bike shop without my bike, and simply asked for a headset. He said he needed to know what angle the bearing was, and there are sundry other options that need to be taken into account as well. He gave me a couple of shims as per post #5 above. I've installed one of the shims, but haven't taken the bike out for a ride yet. In the meantime, here's what was underneath when I removed the top cap and the stem:



I take it this an integrated headset? Funny though, I couldn't get the bearing out for the life of me. I couldn't get any of that black stuff out in the photo. What's the deal with that?

You may have to tap the bearing out from the other side with the fork removed.

I know this was mentioned but is there enough space between the top cap and the star nut/compression plug that the bolt screws into? If not you won't get preload right. You do need about 3mm of space there. You could put an extra spacer on top of the stack and then put the top cap back and see if that makes a difference

Yes, that is an integrated headset. Count your lucky stars.

If the bearing has never been serviced, then yes it would be a bull to get out.

Turn the bike upside down in a work stand, and using a flat-head screwdriver, gently tap it out around the inner edges with a hammer.

You'll want to replace this and the bottom cartridge bearing.

BTW, did you remove the compression ring before taking this pic, or was it missing?