Possibly, the second instance was with an alu steerer, several friends have found the same too. Whilst the top cap shouldn’t do anything at all once the stem is tightened, in reality it does.

I have exactly the same problem.
I started a thread on here and went through all of the checks that people suggested.
The only one left that I haven’t done is replacing the HS (I’ll do it when I believe the HS is knackered).

On-One Ti456, bought new, fully built in December and after every single bloody ride the headset needs the slack taken out (On-One customer service were no help what so ever).

I now tweak it up once a month rather than after every ride.

Are you doing up your stem bolts equally? if they are not tightened equally it could cause some movement. don’t do them up on at a time but do them up little bit each until they are tight.

I tend to tighten the top cap bolt fairly tight to get rid of any play, then tighten the stem bolts, tight and equal, then back the top cap bolt off a bit. seems to work.

Why back the top cap bolt off?

Whilst the top cap shouldn’t do anything at all once the stem is tightened, in reality it does.

This is absolutely true and I doubt that anyone who claims the top cap is not needed has tried riding hard with it removed over a period of time. The stem does get worked a little on the stem by impacts and vibration and without something to stop it being able to move up the steerer freely, it will. This is the same thing that makes thread lock necessary despite the fact that when considered the same way as people are considering stem clamps, nuts and bolts shouldn’t come loose if they are done up properly. It’s worth nipping up the top cap a little more once the stem is clamped for exactly this reason.
Other things to check OP, how much steerer is clamped in the stem? It clamps best when the steerer actually comes right out the top of the stem and you use a spacer on top to allow the top cap to work. Conversely if there is a big gap from the top of the steerer to the top of the stem it will tend to work loose easier.
How good a fit is the stem on the steerer? If you slacken the bolts right off is it a nice tight fit on the steerer or is there play? The better it fits before clamping up, the better it’ll clamp and hold, some stems aren’t very well machined and never hold well.
Is it a standard type stem clamp or one of the hidden wedge type ones? The wedge type ones never clamp right.

robinlaidlaw – Member

This is absolutely true and I doubt that anyone who claims the top cap is not needed has tried riding hard with it removed over a period of time. The stem does get worked a little on the stem by impacts and vibration and without something to stop it being able to move up the steerer freely, it will.

Definitely with this line of thinking. Although it took me many months, a new headset & new stem to come to the same conclusion.

I think the problem was particularly bad on a bike I have with a 130mm travel fork and only a 100mm headtube. The stem has to clamp at a very high force, so close to the crown, to counter the leverage of the fork.

Specialised used to supply some of their cheaper models with plastic top caps – no way will that exert any clamping force.

njee20 – spose it doesn’t really need it once the stem bolts are done up properly. But I always just undo it and re tighten so it’s only nipped up.

I had this problem for a while, turned out I had some grease on my steerer and although I was giving the stem a good tighten it was working loose after a couple of rides. A bit of degreaser on the top of the steerer and the inside of the stem sorted it.

plastic top caps – no way will that exert any clamping force.

More than you’d think, but regardless, the fact they were supplied that way doesn’t mean that it worked well.

But I always just undo it and re tighten so it’s only nipped up.

I’d recommend the opposite, gentle nip to preload, clamp the stem, then tighten the preload bolt up a bit more to stop it working loose.

I’m having the same problem, alloy steerer and stem but I’m going to see if some carbon paste will help

I had this on a Yeti and it turned out to be that the headset wasn’t seated properly when I tightened it up. It looked, felt and sounded like it was fine until I took it out for a ride and it would loosen part way round. Try seating the forks, bearing and headtube, tighten the top cap just a little bit – just enough to hold everything in place – then lift the front of the bike to take the weight of the wheel and try re-seating the bearings.

The other option i can think of is that the waggle is not coming from the headset but from worn bushings in the forks.

I’d recommend the opposite, gentle nip to preload, clamp the stem, then tighten the preload bolt up a bit more to stop it working loose.

Furry muff, but I’ve never had a problem so i’m not gonna change now……

I say nipping it up, but in reality i’m a bit of a brute so my nipping is probably someone else’s full on tightening!!

I’d recommend the opposite, gentle nip to preload, clamp the stem, then tighten the preload bolt up a bit more to stop it working loose.

If you have done your stem up then all you are going to do is put massive stress on the bolt (or snap it). After a ham fisted heat of the moment nip it a bit tighter moment I rode 3/4 of Penmachno with no top cap, after the stem is tightened properly it’s only purpose is decoration.

after the stem is tightened properly it’s only purpose is decoration.

As has been said repeatedly, whilst that’s the theory, in reality if you carry on riding without one your headset will come loose.

all you are going to do is put massive stress on the bolt (or snap it).

I didn’t say to go mental, just take it past “nipped” to “tight” for that bolt size, it’s pretty easy to feel by hand.

I rode 3/4 of Penmachno with no top cap, after the stem is tightened properly it’s only purpose is decoration.

All that proves is that on your bike you don’t need to tighten it every 3/4 of a ride without the top cap in place, try leaving it off for a year and if it still doesn’t come loose then perhaps you can claim that it’s not required, at least on your bike.
I’m not just guessing, I’ve tried this both ways on a BMX and you honestly do need the cap if the bike is being ridden hard.

decoration, and to stop any slippage of the stem.

could be settling of bearings, cups, crown race. have seen crown race not fit leaving a 1mm gap, and the torque needed on top cap bolt to get it in place would round out the bolt at best, or snap it. Mine are all Hope, with split race, so can be sure they fit properly.

I’d have stem off, degrease stem above top bearing, degrease inside of stem clamp, and try again. In fact I usually do that anyway, since poking forks up thru headset bearings can get grease on the clamping area anyway.

Presumably the forks are tapered? I had problems with the straight steerer and adapters on my 301, but it was largely creaking.

I hope you dont have the same problem (see below) I did; Liteville fixed it under warranty but it was a right faff
Date: 10 April 2014 21:36:02 BDT
To: syntace@syntace.de
Cc: Phillip Morgan <phillipmorgan@onetel.com>
Subject: Liteville 301

hi

my Liteville was purchased on 28/2/2013 and has developed a problem. I have noticed a little movement in the steering when pushing the bike forward & backward with the front brake on. Over the last 6 months I have been trying to find the cause eg brakes & pads, wheel bearings, fork bushes etc but with no progress.

Today I decided to take the forks and steering apart & check the headset bearings & clean the components. When I started the rebuilding process I felt some movement in the top bearing and realised the whole bearing assembly is loose and it moves around a little in the steering tube; when I push the fork into place I can feel & see the little movement on the contact face.

It is no longer a press fit into the head tube; it is easy just to pull it out- it would fall out if the bike is upside down. I have made some measurements using my vernier caliper

Frame head tube Inside diameter: largest 49.35mm smallest 49.10mm

Bearing outer diameter: smallest 48.92mm largest 49.00mm

Please can you advise what I should do