Play in forks

[Bodhbh]

Hi all, as above. There's a little bit of play in the forks on my MTB. Not really noticable while riding, but you can confirm it's there easy enough by locking the wheel with the brakes and rocking the bike back and forth (if you lock the front and back brake alternately and apply forward pressure, you can 'walk' it forward slowly). It started to irritate me as the bike took time to get setup how I liked and everything else is finally in order.

I've changed the headset, it's still there, exactly as before. I've got a facing tool for the forks and faced them, used a headset clamp to fit that, so all by the book. Any ideas to the cause? Should I just ignore it?

I guess my main concern is it might be a crack in teh frame which is not visable or something . It's an aluminium Rockhopper frame, Kona P2 forks and Cane Creek S3 headset for what it's worth

 

[accountantpete]

Have you tightened up the top nut quite tight so that the forks turn with a judder and tested for play then?

 

[Bodhbh]

Have you tightened up the top nut quite tight so that the forks turn with a judder and tested for play then?

I did tighten it up such that the turning was no longer entirely free (i.e. you wouldn't want to ride none handed) and it did reduce the play a bit. In the end though I loosed it off, as I do like to take my hands off the bars sometimes and also I didn't think it was doing the bearings anygood.

I've not tried tightening it up to the extent that you have to use force or they juddger although.

 

[accountantpete]

I did tighten it up such that the turning was no longer entirely free (i.e. you wouldn't want to ride none handed) and it did reduce the play a bit. In the end though I loosed it off, as I do like to take my hands off the bars sometimes and also I didn't think it was doing the bearings anygood.

I've not tried tightening it up to the extent that you have to use force or they juddger although.

I'd try (but don't ride the bike) tightening up as I suggest and see if the play is still present. If it cures it then you can gradually ease it off until the forks move more freely but without the play.

Did you replace the Crown Race by the way?

 

[MartinC]

You need to find out where the play is. Put the front brake on hard and rock the bikr backwards and forwards. Look at the front end carefully and see where the play is. If you can see movement between the fork crown and the bottom of the head tube then the play is in the headset. It might be movement in the brake that you can see.

 

[Alien8]

You need to find out where the play is. Put the front brake on hard and rock the bikr backwards and forwards. Look at the front end carefully and see where the play is. If you can see movement between the fork crown and the bottom of the head tube then the play is in the headset. It might be movement in the brake that you can see.

Yes, and if you place a finger along the fork-crown head-tube gap you should be able to feel relative movement between the two.

 

[piedwagtail91]

to check for headset play you really need to hold the bike by one side of the forks (or both fork arms with the wheel out) and the handlebar stem to see if there is movement.
you don't say what sort of brakes you have on but you can get movement that appears to be the headset moving when it's the brakes on their bushes if you have v's on.
if there is movement then things need tightening up. if this stops the forks turning then i would check that you've got the right size bearing above and below, because in some headsets (i think it was a campag headset with me) they are different sizes and this can lead to play or the problem you describe if the bottom set is in the top.

 

[Bodhbh]

I'd try (but don't ride the bike) tightening up as I suggest and see if the play is still present. If it cures it then you can gradually ease it off until the forks move more freely but without the play.

Did you replace the Crown Race by the way?

Yes, I replaced the race. I'll give the above a go (wish I had b4 replacing the headset, but oh well, the old one will get used on something eventually).

MartinC: I'm pretty sure it's not the brakes (discs). I've had problems b4 with the disc nuts working loose giving a similar problem, but they're currently rock solid, as are the brakes.

 

[Bodhbh]

to check for headset play you really need to hold the bike by one side of the forks (or both fork arms with the wheel out) and the handlebar stem to see if there is movement.....

if there is movement then things need tightening up. if this stops the forks turning then i would check that you've got the right size bearing above and below, because in some headsets (i think it was a campag headset with me) they are different sizes and this can lead to play or the problem you describe if the bottom set is in the top.

I had the wheel out last night. I checked for play then, and there seemed to be, although it's quite hard to feel it when it's fairly subtle. I probably should have turned it the right way, stuck the forks on the floor and tried to rock it. The both headsets I've tried have the cartridge bearing that come with them, so it shouldn't be them not fitting.

 

[snailracer]

I did tighten it up such that the turning was no longer entirely free (i.e. you wouldn't want to ride none handed) and it did reduce the play a bit. In the end though I loosed it off, as I do like to take my hands off the bars sometimes and also I didn't think it was doing the bearings anygood.

I've not tried tightening it up to the extent that you have to use force or they juddger although.

After tightening the nut, did you remount the stem to take up the play? I am assuming it is a threadless headset.

 

[Bodhbh]

After tightening the nut, did you remount the stem to take up the play? I am assuming it is a threadless headset.

I did loosen the stem bolts if that's what you mean?

I tried tightening up the top cap bolt earlier, it got tighter up to a point, then it seems to be pulling the star nut up the tube. The play did not go away. Maybe this is the issue - a loose star nut. It would explain why changing the headset did not solve the problem. I googled a bit on this, and seems you can solve the problem with this:

http://www.chainreactioncycles.com/Models.aspx?PartnerID=79&ModelID=48381

Although I have some spare star nuts about, I probably should knock the old one through/pull it out and try a new one first. I said it wasn't effecting handling, but noticed today it does make the bike feel unstable doing very tight cornering and braking. It's irritating and needs fixing.

 

[zigzag]

are you completely sure that it is headset that is loose? very similar "looseness" can be caused by loose cup and cone bearings in the front hub. if it's definitely headset and everything is set up as it should be, it's not easy to give advice online without actually seeing the bike.

 

[PapaZita]

A handy trick is to turn the front wheel 90 degrees and do the same rocking test. If the movement is just play in the brakes then this tends to reduce it significantly. Play in the hub can be diagnosed quickly by waggling the wheel in the forks.

I had a problem once with a headset that I couldn't get adjusted. It turned out that the lower headset cup was moving in the frame, just a tiny bit. Not sure if the frame was damaged, or whether the cup was fractionally too small. A splash of stud locking compound (like a thread lock, but stronger and more permanent) and it's running fine to this day.

PZ.

 

[Gerry Attrick]

Have you checked for play in the front suspension? The bushing between the sliders and stanchions can wear and give a good impression of a loose headset.

Walking the bike by pushing it whilst alternately operating front and rear brakes proves precisely nowt. You can do that with any bike owing to fork flex and lost brake motion.

 

[Norm]

Have you checked for play in the front suspension? The bushing between the sliders and stanchions can wear and give a good impression of a loose headset.

This one is my guess. Using your hand to feel the joins (top and bottom of head tube and around the sliders for the suspension) when you are rocking it will confirm exactly where the movement is originating. Many, if not most, front suspension units will have some play in them.

TBH, though, that check takes seconds. I'd be very surprised if you didn't do that before spending any money replacing anything.