re ahead headset bearings

geepeetee said:

Hi

I am intrigued now, the headset really doesn't have bearings.

I don't believe that. Have you removed the stem and forks yet to look
inside?

Quoted message said:

The
headtube is slightly conical at both ends and a circular split bush
compresses into the headtube when the central allen screw is
tightened. I have googled for it but cant find any info or images.

The bike is a trek 7200 hybrid.

Integrated headset?
http://www.parktool.com/repair/readhowto.asp?id=68

Do you really mean head tube or steer tube?

Does it have anything like this:
http://www.chainreactioncycles.com/Models.aspx?ModelID=2741 ?

~PB

On 16/09/2006 18:18, geepeetee said,

Quoted message said:

I am intrigued now, the headset really doesn't have bearings. The headtube
is slightly conical at both ends and a circular split bush compresses into
the headtube when the central allen screw is tightened. I have googled for
it but cant find any info or images.

*ALL* headsets use bearings, AFAIK. Are you able to take photos
yourself of what you have, and post them somewhere?

--
Paul Boyd
http://www.paul-boyd.co.uk/

Actually, from the description it sounds more like it has this sort of
thing:

http://www.chainreactioncycles.com/Models.aspx?ModelID=2218

- Used for pressing the the stem down, which in turn loads the headset
beaings.

Apologies if I'm egg-suck teaching.

~PB

In article <[email hidden]>

Paul Boyd said:

On 16/09/2006 18:18, geepeetee said,

Quoted message said:

I am intrigued now, the headset really doesn't have bearings. The headtube
is slightly conical at both ends and a circular split bush compresses into
the headtube when the central allen screw is tightened. I have googled for
it but cant find any info or images.

*ALL* headsets use bearings, AFAIK. Are you able to take photos
yourself of what you have, and post them somewhere?

Some small-wheelers have a ball race at the bottom and a nylon bush at
the top.

geepeetee said:

Hi

I am intrigued now, the headset really doesn't have bearings. The headtube
is slightly conical at both ends and a circular split bush compresses into
the headtube when the central allen screw is tightened. I have googled for
it but cant find any info or images.

The bike is a trek 7200 hybrid.

thanks

Gary

--
Visit my websites at
www.justjents.co.uk
www.recumbent.50megs.com

Try harder :{
http://www.trekbike.co.uk/2007/bikes.php?sec=spec&MainCatID=3&SubCatID=9&RangeID=16&ID=255
says:HEADSET: VP semi-cartridge

"Pete Biggs" <[email hidden]> a écrit:

Quoted message said:

Actually, from the description it sounds more like it has this sort of
thing:

Quoted message said:

http://www.chainreactioncycles.com/Models.aspx?ModelID=2218

Quoted message said:

- Used for pressing the the stem down, which in turn loads the
headset beaings.

Quoted message said:

Apologies if I'm egg-suck teaching.

I think you're probably misreading between the lines.

"The headtube is slightly conical at both ends and a circular split bush
compresses into the headtube when the central allen screw is tightened."

Many threadless headsets one or more split conical compression rings to
provide radial preload when the top bolt is tightened. In a cartridge
bearing headset, the lower ring often replaces the crown race.

The Trek site says "VP semi cartridge":

http://www.trekbike.co.uk/2007/bikes.php?sec=spec&MainCatID=3&SubCatID=9&RangeID=16&ID=255

and shows a headset with external cups and a tall conical spacer:

http://www.trekbike.co.uk/2006/bike_images/07_7200.jpg

http://www.bicyclestore.com.au/files/master/ProductDetailImages/d_2338.jpg

The VP site shows a similar looking headset, the Slimstak:

http://www.vpcomponents.com/images/ProdAD2.jpg

http://www.vpcomponents.com/headset_show.asp?pid=40

It's called semi-integrated beacause the cups sit flush with the head tube,
but it's basically a conventional Aheadset.

James Thomson

Paul Boyd said:

Quoted message said:

*ALL* headsets use bearings, AFAIK.

"Rob Morley" <[email hidden]> a écrit:

Quoted message said:

Some small-wheelers have a ball race at the bottom and a nylon
bush at the top.

Raleigh Twenties being a common example. Of course it's still a bearing,
just not a ball bearing.

There was a plastic headset in the early eighties that used, IIRC, Delrin
cups and PTFE bushes top and bottom. I don't recall the brand, but they
didn't stay long on the market.

James Thomson

In article <[email hidden]>

James Thomson said:

Paul Boyd said:

Quoted message said:

*ALL* headsets use bearings, AFAIK.

"Rob Morley" <[email hidden]> a écrit:

Quoted message said:

Some small-wheelers have a ball race at the bottom and a nylon
bush at the top.

Raleigh Twenties being a common example. Of course it's still a bearing,
just not a ball bearing.

Indeed - but when most people say 'bearings' they mean 'balls' :-)

James Thomson said:

I think you're probably misreading between the lines.

You must be right.

Sorry Gary. Please ignore my replies on the subject.

~PB

In article <[email hidden]>,

James Thomson said:

There was a plastic headset in the early eighties that used, IIRC,
Delrin cups and PTFE bushes top and bottom. I don't recall the
brand, but they didn't stay long on the market.

Elswick Hopper IMMIC - I had about 30 of them but they didn't last.

--
A T (Sandy) Morton
on the Bicycle Island
In the Global Village
http://www.millport.net