Headset

Brendo said:

For reference, it is a Reynolds Ouzo fork, inside a 22cm steering
tube. The cap and spacer thing are FSA, but it isn't the pspring
tensioned one.

I'm assuming since it's an Ouzo that this is road Ahead. Step 1 should be
to make sure the steerer is free of grease, at least under the stem. Now
tighten the top cap bolt until there is no wobble, and then around 1/8
turn more. Make sure the fork turns freely. Finally tighten the pinch
bolts on the stem. If it's a single bolt then tighten to approximately
rated spec (should be on a sticker), if it's twin bolt then tighten both
to the limits of pinching the allen key's shaft, then go for around 1/4
turn on each bolt in turn until neither will turn anymore at the rated
spec.

As far as rated specification goes - off the top of my head it's normally
around 5 Nm, which is very roughly equivalent to hanging a 5kg mass at
10cm - so if you're applying about the force to lift a half full bucket on
the end of a longish allen key then you'll be in the ball park.

--
Dave Hughes | [email hidden]
Remember Jeebus loves you. Or maybe he's just sucking up to get your old
bike bits. - Phil Las Gourgues

Dave said:

Brendo said:

For reference, it is a Reynolds Ouzo fork, inside a 22cm steering
tube. The cap and spacer thing are FSA, but it isn't the pspring
tensioned one.

I'm assuming since it's an Ouzo that this is road Ahead. Step 1 should be
to make sure the steerer is free of grease, at least under the stem. Now
tighten the top cap bolt until there is no wobble, and then around 1/8
turn more. Make sure the fork turns freely. Finally tighten the pinch
bolts on the stem. If it's a single bolt then tighten to approximately
rated spec (should be on a sticker), if it's twin bolt then tighten both
to the limits of pinching the allen key's shaft, then go for around 1/4
turn on each bolt in turn until neither will turn anymore at the rated
spec.

As far as rated specification goes - off the top of my head it's normally
around 5 Nm, which is very roughly equivalent to hanging a 5kg mass at
10cm - so if you're applying about the force to lift a half full bucket on
the end of a longish allen key then you'll be in the ball park.

Thanks Dave.

When you say cap bolt, do you mean the cap itself or the hex bolt
underneath it? This one has a circular piece aroun 10mm thick,
with an 'O' ring around it, and by tightening the bolt you spread
the circular piece by drawing a conical section through the
centre of it. The cap then screws onto the thread on the conical
piece. I am sure there are proper names for these pieces, but I
don't know them.

If I keep tightening the cap, then I think it is drawing the
circular piece up the inside of the steerer.

Brendo

Brendo said:

When you say cap bolt, do you mean the cap itself or the hex bolt
underneath it? This one has a circular piece aroun 10mm thick,
with an 'O' ring around it, and by tightening the bolt you spread
the circular piece by drawing a conical section through the
centre of it. The cap then screws onto the thread on the conical
piece. I am sure there are proper names for these pieces, but I
don't know them.

There's the problem. You've got a wedge instead of a star fangled nut.
Loosen it a couple of turns, then tap the bolt to loosen the wedge. Pull
it out and wipe the inside of the steerer tube and the outside of the
wedge clean. Then reinstall. The wedge should sit firmly, since that's
what you're using to preload the bearings. If it's sliding, as they often
can, then you're not getting the correct preload.

From memory the Ouzo has a metal steerer, so if that doesn't work take it
to your LBS and pay $10 or so to have a star nut bashed into the top. That
won't move, and you simply use a 5mm bolt through a cap on top to preload
the bearings. Option C is to get a Headlock, which is a very long
threaded two piece threaded rod with a cap on each end which goes all the
way through the steerer to achieve the same thing. It weighs more, but you
can pull it out once the stem is tight.

--
Dave Hughes | [email hidden]
I think it's a beautiful day to go to the zoo and feed the ducks.
To the lions. -- Brian Kantor

Dave said:

Brendo said:

When you say cap bolt, do you mean the cap itself or the hex bolt
underneath it? This one has a circular piece aroun 10mm thick,
with an 'O' ring around it, and by tightening the bolt you spread
the circular piece by drawing a conical section through the
centre of it. The cap then screws onto the thread on the conical
piece. I am sure there are proper names for these pieces, but I
don't know them.

There's the problem. You've got a wedge instead of a star fangled nut.
Loosen it a couple of turns, then tap the bolt to loosen the wedge. Pull
it out and wipe the inside of the steerer tube and the outside of the
wedge clean. Then reinstall. The wedge should sit firmly, since that's
what you're using to preload the bearings. If it's sliding, as they often
can, then you're not getting the correct preload.

From memory the Ouzo has a metal steerer, so if that doesn't work take it
to your LBS and pay $10 or so to have a star nut bashed into the top.

It's a carbon steerer. What I might try is to pull it out, clean
both the inside of the steerer and the 'O' ring, and then tighten
the [censored] out of it (within reason), so it can't move at all.

Are these generally a cruddy version of tensioning the steerer?

Brendo

Brendo said:

Are these generally a cruddy version of tensioning the steerer?

Yes and no. If they've got oil or grease on the binding surfaces, they're
a pig to get right. On the other hand they're a lot less likely to break a
lightweight steerer than the star nut. Clean it up and it should bind. You
can also pretension the wedge a bit by putting a spacer in between the top
cap and the wedge so that it isn't being pulled up the steerer. Tighten to
about the right level, then pull the bolt out and take the spacer off. The
wedge should stay in place. Take very careful note of any torque
specifications, because cracked carbon in a steerer is a recipe for
disaster.

Bleve, do you have any other ideas for getting a wedge to stick in a carbon
steerer?

--
Dave Hughes | [email hidden]
Thus leading us to the obvious conclusion that all software should look
like a nipple. - Eric the Read

Dave said:

Bleve, do you have any other ideas for getting a wedge to stick in a
carbon steerer?

I've had two done at Quantum Bicycles in Perth (a frame builder) and both of
them they've machined an aluminium plug to fit inside the steerer with a
threaded hole through the middle for the tensioner bolt to screw into, and
epoxied the plug into the steerer with that special epoxy that one uses for
assembling frames made of carbon fibre tubes...has worked much better than
those damn slipping expander things.

Cheers
David M

Dave said:

Bleve, do you have any other ideas for getting a wedge to stick in a carbon
steerer?

Nope! I'm gaining a lot from reading your descriptions 🙂
My bikes are all alloy steerers, and generally we don't swap a lot of
road forks around, it's not something I've come across.

Bleve said:

Nope! I'm gaining a lot from reading your descriptions 🙂
My bikes are all alloy steerers, and generally we don't swap a lot of
road forks around, it's not something I've come across.

Assuming you don't already have one at the LBS I'd highly recommend
getting one of the Amoeba headlock style things (a few people do/have made
them). I've got one on my silly SS at the moment because the steerer is
about 1cm shorter than it really should be. The stem seems OK, but having
something that is reasonably solid holding it on just in case is
comforting, especially since you do tend to pull up on the bars a bit
going up hills.

Anyway, having something that'll pull the headset together without loading
up the steerer at all is something that could be quite useful in a workshop.

A trail fix if you don't have a working preload mechanism is to lock the
brake and push the stem down as hard as possible. If you've got a tree or
sign nearby you could probably get a mate to stand on it while you hold
the brake and tighten the pinch bolt. This is dodgy, potentially dangerous,
and highly inaccurate in the tension applied to the bearings. OTOH it's a
*trail fix*, and riding out beats walking any day.

--
Dave Hughes | [email hidden]
Mr Tulip's vices were also limitless, but he owned up to cheap
aftershave because a man has to drink *something* -- Terry Pratchett