seat post size?

[Steve W]

What is the correct seat post size for an old Holdsworth (Roy Thame) frame.
26.8 is loose amd 27.2 seems too tight although it will start to go in. So
my guess is that 27mm will be correct but I would like confirmation before I
go ahead and buy.

thanks
SW

 

[Michael Dart]

Steve W wrote:
> What is the correct seat post size for an old Holdsworth (Roy Thame)
> frame.
> 26.8 is loose amd 27.2 seems too tight although it will start to go
> in. So my guess is that 27mm will be correct but I would like
> confirmation before I go ahead and buy.
>
> thanks
> SW

See if your lbs has one of those seat tube measuring thingys.

Mike

 

[Qui si parla Campagnolo]

Steve W wrote:
> What is the correct seat post size for an old Holdsworth (Roy Thame) frame.
> 26.8 is loose amd 27.2 seems too tight although it will start to go in. So
> my guess is that 27mm will be correct but I would like confirmation before I
> go ahead and buy.
>
> thanks
> SW

Is the seat tube inside smooth, prepped?

If it isn't, take a flex hone to it...make it smooth and then see. I'm
guessing 27.2

 

[Steve W]

Thanks, but what is a flex hone? Could it be a drill with a a small mandril
and some emery cloth?

SW in the UK


"Qui si parla Campagnolo" <[email protected]> wrote in message
news:[email protected]...
>
> Steve W wrote:
>> What is the correct seat post size for an old Holdsworth (Roy Thame)
>> frame.
>> 26.8 is loose amd 27.2 seems too tight although it will start to go in.
>> So
>> my guess is that 27mm will be correct but I would like confirmation
>> before I
>> go ahead and buy.
>>
>> thanks
>> SW
>
> Is the seat tube inside smooth, prepped?
>
> If it isn't, take a flex hone to it...make it smooth and then see. I'm
> guessing 27.2
>

 

[A Muzi]

Steve W wrote:
> What is the correct seat post size for an old Holdsworth (Roy Thame) frame.
> 26.8 is loose amd 27.2 seems too tight although it will start to go in. So
> my guess is that 27mm will be correct but I would like confirmation before I
> go ahead and buy.

Reynolds 531 tube, the most likely material, in the most
likely gage Roy would have used, should be 27.2.

As with any steel frame, look at the seat lug from behind
with the bolt removed. Is the slit a neat rectangle? Or
are the tops a bit closer together? It is all to common for
bikes to be subjected to either a too-small post or to being
tightened with no post in place.

If that's the case, jam a 27.2 post in about 12-15mm and
push it straight back until the slit has parallel sides. If
the 27.2 post now fits nicely you're done!

--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971

 

[philcycles]

A Muzi wrote:
> Steve W wrote:
> > What is the correct seat post size for an old Holdsworth (Roy Thame) frame.
> > 26.8 is loose amd 27.2 seems too tight although it will start to go in. So
> > my guess is that 27mm will be correct but I would like confirmation before I
> > go ahead and buy.
>
> Reynolds 531 tube, the most likely material, in the most
> likely gage Roy would have used, should be 27.2.
>
> As with any steel frame, look at the seat lug from behind
> with the bolt removed. Is the slit a neat rectangle? Or
> are the tops a bit closer together? It is all to common for
> bikes to be subjected to either a too-small post or to being
> tightened with no post in place.
>
> If that's the case, jam a 27.2 post in about 12-15mm and
> push it straight back until the slit has parallel sides. If
> the 27.2 post now fits nicely you're done!
>
> --
> Andrew Muzi
> www.yellowjersey.org
> Open every day since 1 April, 1971


I have a slight disagreeement here. It is most likely that the seat
tube has been slightly crushed because a nominal .9/.6 531 seat
tube-the most likely on the Holdsworth-is happiest with a 27.4 seat
tube. Every 531 bike I've ever built has been happiest with a 27.4
post. A 27.2 is slightly loose-but seems OK-and results in a slightly
crushed seat tube. So I'd try to open the slot a bit and try again.
Phil Brown

 

[Steve W]

Thanks guys, I'll give it a try and report back.

SW in the UK


"philcycles" <[email protected]> wrote in message
news:[email protected]...
>
> A Muzi wrote:
>> Steve W wrote:
>> > What is the correct seat post size for an old Holdsworth (Roy Thame)
>> > frame.
>> > 26.8 is loose amd 27.2 seems too tight although it will start to go in.
>> > So
>> > my guess is that 27mm will be correct but I would like confirmation
>> > before I
>> > go ahead and buy.
>>
>> Reynolds 531 tube, the most likely material, in the most
>> likely gage Roy would have used, should be 27.2.
>>
>> As with any steel frame, look at the seat lug from behind
>> with the bolt removed. Is the slit a neat rectangle? Or
>> are the tops a bit closer together? It is all to common for
>> bikes to be subjected to either a too-small post or to being
>> tightened with no post in place.
>>
>> If that's the case, jam a 27.2 post in about 12-15mm and
>> push it straight back until the slit has parallel sides. If
>> the 27.2 post now fits nicely you're done!
>>
>> --
>> Andrew Muzi
>> www.yellowjersey.org
>> Open every day since 1 April, 1971
>
>
> I have a slight disagreeement here. It is most likely that the seat
> tube has been slightly crushed because a nominal .9/.6 531 seat
> tube-the most likely on the Holdsworth-is happiest with a 27.4 seat
> tube. Every 531 bike I've ever built has been happiest with a 27.4
> post. A 27.2 is slightly loose-but seems OK-and results in a slightly
> crushed seat tube. So I'd try to open the slot a bit and try again.
> Phil Brown
>

 

[A Muzi]

>>Steve W wrote:
>>>What is the correct seat post size for an old Holdsworth (Roy Thame) frame.
>>>26.8 is loose amd 27.2 seems too tight although it will start to go in. So
>>>my guess is that 27mm will be correct but I would like confirmation before I
>>>go ahead and buy.

> A Muzi wrote:
>>Reynolds 531 tube, the most likely material, in the most
>>likely gage Roy would have used, should be 27.2.
>>As with any steel frame, look at the seat lug from behind
>>with the bolt removed. Is the slit a neat rectangle? Or
>>are the tops a bit closer together? It is all to common for
>>bikes to be subjected to either a too-small post or to being
>>tightened with no post in place.
>>If that's the case, jam a 27.2 post in about 12-15mm and
>>push it straight back until the slit has parallel sides. If
>>the 27.2 post now fits nicely you're done!

philcycles wrote:
> I have a slight disagreeement here. It is most likely that the seat
> tube has been slightly crushed because a nominal .9/.6 531 seat
> tube-the most likely on the Holdsworth-is happiest with a 27.4 seat
> tube. Every 531 bike I've ever built has been happiest with a 27.4
> post. A 27.2 is slightly loose-but seems OK-and results in a slightly
> crushed seat tube. So I'd try to open the slot a bit and try again.
> Phil Brown
>
OK that's a reasonable thing to check.

If, after opening the slit and clearing any detritus, a 27.2
post has any play when inserted all the way in, then, yes,
get a 27.4 post.

I don't agree that's likely. But yes, it is possible. A seat
post should slip in all the way without effort and then not
rock inside the tube.

--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971

 

[Qui si parla Campagnolo]

Steve W wrote:
> Thanks, but what is a flex hone? Could it be a drill with a a small mandril
> and some emery cloth?
>
> SW in the UK

see

http://www.mytoolstore.com/kd/kdengi09.html#2492

Drill mounted, little abrasive balls on it to smooth the seattube.

 

[Steve W]

OK, after all your recommendations it turns out to be 27.2. I suspect that
the seat post I have is fractionally oversize but having cleaned the seat
tube it fits OK and no play at all.
Thanks for all the input

SW


"Steve W" <[email protected]> wrote in message
news:[email protected]...
> What is the correct seat post size for an old Holdsworth (Roy Thame)
> frame. 26.8 is loose amd 27.2 seems too tight although it will start to go
> in. So my guess is that 27mm will be correct but I would like
> confirmation before I go ahead and buy.
>
> thanks
> SW
>