head set wont stay tight

Crock - SmP

my headset on my onza t-mag wont stay tight?

any ideas?

nicklouse

tighten the stem bolts up more.

Crock - SmP

i'll give it a go but i've tightened them to the tighes i can physicly do.

nicklouse

Ok then 2 things make sure that both the steerer tube and the stem are spotless and a head lock might help.

alfablue

Make sure there is a small gap of about 2mm between the top of the stem and the steerer tube, otherwise the headset top cap will be prevented from tightening the headset bearings correctly. Like this:


(from the Park Tools threadless headset service page).

Also, make sure you tighten the headset cap (and tension the bearing) before tightening the stem bolts.

Crock - SmP

i may purchase a head lock at a later deate and i'll give everythign a wipe down thatnks ill come back aif it doesnt work.

Crock - SmP

yeh i've done all that checked the gap and everything but it seems not to tighten fully thers always alittle bit of movment.

alfablue

Star fangled nut slipped / not deep enough?

nicklouse

OK this is in set up, not use?

3 things. 1 you are not doing it correctly.
2 something is missing/incorrectly fitted.
3 headset worn out.

Crock - SmP

i know i'm doing it correctly for a fact as i've done it many a time.
as far as i know everythings there still stock spec from perchase
i doubt its worn out havnt had it that long (7 months) only had about 2-3 months riding

the start nut might be the problem.

nicklouse

the star nut will onlt be a problem if it is not far enough down the steerer and is contacting the top cap and therefor stopping you preloading the bearings. ( see note 2)

Crock - SmP

i may be slipping up the stere tube how do i stop that?

nicklouse

Crock - SmP wrote:

i may be slipping up the stere tube how do i stop that?

make sure the stem is tight. or use a head lock.

Crock - SmP

ok. but i ment the start but may be slipping.

nicklouse

Crock - SmP wrote:

ok. but i ment the start but may be slipping.

make sure the stem is tight. or use a head lock.

same answer to what i guess is the same question.

Crock - SmP

i know the head lock is the answer if i cant find any other way.

but i didnt mean stem i ment start nut?

alfablue

you may be able to tell if its slipping in the steerer tube by inserting the bolt without the head cap and pulling up with pliers - it shouldn't move at all. If it is you probably need a new one as it will have lost its "spring" (they aren't really re-usable). It can be tapped through the bottom of the fork with a long screwdriver.

Rather than a star nut you may find a stem plug like this




is more reliable, and a bit cheaper than a headlock.

nicklouse

yes and the answer is the same make sure the stem is tight. or use a head lock.

if the headset has been plealoaded and then the stem bolts are tight that should hold every thing together. But as you are pulling up on the bars a lot if the stem is not clamping correctly then you will be reliying on the star nut to help keep the stem on the steerer and things will move and the headset will get lose.

so as i said make sure the stem is tight. or use a head lock.

if the stem is as tight and is posible and it still moves have it replaced and get a head lock.

Crock - SmP

well i'll give the plier thing ago if its nackered i'll grab on of those stem plug's?

how do they work same as a star nut

alfablue

They don't work the same as a star nut, there is nothing inserted in the tube first.

Instead the plug is inserted as one piece and tightened - there is a wedge-shaped flange which expands and grips the inside of the steerer tube as the bolt is tightened - very easy to use, and can easily be removed and re-used.

nicklouse

alfablue wrote:

They don't work the same as a star nut, there is nothing inserted in the tube first.

Instead the plug is inserted as one piece and tightened - there is a wedge-shaped flange which expands and grips the inside of the steerer tube as the bolt is tightened - very easy to use, and can easily be removed and re-used.

but again not really that suitable on a trials bike as they have been known to slip as well.

SiLvEr_SnAkE

I used a stem plug (the x-lite one shown above) on my HT XC bike and it was fine, after switching to a FS Freeride bike I found it would slip so I went for a headlock.

Crock - SmP

i think i'll go for the head lock then and a new stem because i've just tightened it tilli acidently bent the bolts :S dont as k me how becuase i dont know.


thanks for all your advice sorry nick should of listened in the 1st place.