Headset problem

ade555

I'm having a bit of problem with headset on my Kona Blast 2011, in short when you rock the bike forward and backwards there is play that you can feel on handles bar and also visual movement on upper part of headset, so I removed stem and tried to resit ( only what I can describe collar that has cut, don't know the technical term) as I could see was a bit lose,so I pressed this in and this sorted the problem until I tried to go for a ride, after first bump same problem.

I did re tighten top cap on stem and stem it self but for some reason this plastic collar still pops up. Only thing I can think of is just worn out, anyone have any solution or advice?

Thanks

ade555

I found out the correct term for the part that always comes lose, compression ring, also feels like the star nut is moving up when trying to tighten top cap, this would explain why compression ring pops up once I go over bump but I still have the stem tight.

Anyone?

larkim

The top cap / star nut should pre-load it, but once that's happened everything else should stay put with the stem securing the top and the crown of the forks securing the bottom. There shouldn't be room for the compression ring to go anywhere.

Are you tightening things up when its in a workstand off the floor, or with the wheel on the floor? After you've tightened up the stem, are you sure there's no movement at all? And after it's gone wonky, is the stem in exactly the same place as when you tightened things up, or has it moved upwards a little?

The Rookie

The compression ring can't move up if the stem (or spacer) is on top of it as it should be.

A photo would be helpful in the assembled condition.

When assembled before the top cap is fitted how far below the top of the stem (or top spacer) is the top of the steerer? When assembled can you rotate a spacer (above or below the stem) easily?

ade555

I think I found a problem, star nut inside tube is split in one place that's why when I try to pre load with top cup it works until I hit a bump. Will go get new one and report back.

larkim

Star nut / top cap have no structural responsibilities when riding - you should be able to leave it off completely and the stem grip the steerer to prevent any movement.

It sounds like you're not tightening up the stem enough so that its slipping when you're riding it.

Of course, if the star nut is slipping then the preloading may also not be "preloading" enough, though I'd have thought you'd notice that by seeing play in the mechanism before you go out to ride.

The Rookie

larkim wrote:

It sounds like you're not tightening up the stem enough so that its slipping when you're riding it.

Which may be because the star nut is FUBAR of course!

But I agree, the star nut and top cap do nothing once the stem is done up.

larkim

(I meant tightening the stem around the steerer so it slips up and down the steerer when riding, rather than pressed tight down on the headset, but that wasn't clear!)

ade555

New star nut fitted now, pre loaded and made sure this time that stem is tight, actually should have mention before that I notice this after fitting new stem "truvative ebay special", maybe it was bit lose( felt tight and handle bar was going together with wheel the direction I wanted to go) , will upload pic of star nut later you can see where it split.

When I was tightening bolts on stem I did notice today that is not perfectly machined where there bolt head goes in but I'm 1000% sure now is tight, luckily it only happen outside my house when I drooped down from curb and not somewhere far away.

I would say id down to maybe poor quality finish of stem and my rush service yesterday and not checking correctly, lesson learned.

Now is everything working like it should.