I'm currrently looking for a longer 28.6 diameter seatpost than the one I have now. I've seen one which is 410mm in length which will definately be too long - is it 'acceptable' to cut the length down in such instances? (btw I have a full-suspension bike)
Regards,
--
John Latter
Model of an Internal Evolutionary Mechanism (based on an extension to homeostasis) linking Stationary-Phase Mutations to the Baldwin Effect. members.aol.comTEM.htmlOpen ↗
"John Latter" <[email hidden]> wrote in message "]news:[email hidden]...
Quoted message said:
Hi,
I'm currrently looking for a longer 28.6 diameter seatpost than the one I have now. I've seen one which is 410mm in length which will definately be too long - is it 'acceptable' to cut the length down in such instances? (btw I have a full-suspension bike)
Regards,
--
John Latter
Model of an Internal Evolutionary Mechanism (based on an extension to
homeostasis) linking Stationary-Phase Mutations to the Baldwin Effect.
I cut mine down to allow the seat to be dropped to an 'acceptable' level for singletrack riding, with no apparent bad side effects. Obviously, if you're doing it for a similar reason, ensure you hit the happy medium of leaving enough to ensure a comfortable ride, whilst removing enough to allow it to drop as far as is needed. Also, you need to ensure that sufficient is left in whatever downtube arrangement you have when the seat is at its highest point to safely hold the seatpost. HTH but if it don't make much sense, apologies, feeling a bit fluffy headed this a.m. Cheers, Dave.
I'm currently looking for a longer 28.6 diameter seatpost than the one I have now. I've seen one which is 410mm in length which will definitely be too long - is it 'acceptable' to cut the length down in such instances? (btw I have a full-suspension bike)
Yes, as long as there's enough post in the tube to keep it secure and stop it levering out. It would depend on things I won't speculate on how much you can trim it, but should be the case that anything hanging out the bottom of the tube won't do anything useful for you.
Pete. -- Peter Clinch University of Dundee Tel 44 1382 660111 ext. 33637 Medical Physics, Ninewells Hospital Fax 44 1382 640177 Dundee DD1 9SY Scotland UK net [email hidden] dundee.ac.uk~pjclinchOpen ↗
"John Latter" <[email hidden]> wrote in message "]news:[email hidden]...
Quoted message said:
Hi,
I'm currrently looking for a longer 28.6 diameter seatpost than the one I have now. I've seen one which is 410mm in length which will definately be too long - is it 'acceptable' to cut the length down in such instances? (btw I have a full-suspension bike)
Regards,
--
John Latter
Model of an Internal Evolutionary Mechanism (based on an extension to
homeostasis) linking Stationary-Phase Mutations to the Baldwin Effect.
I cut mine down to allow the seat to be dropped to an 'acceptable' level for singletrack riding, with no apparent bad side effects. Obviously, if you're doing it for a similar reason, ensure you hit the happy medium of leaving enough to ensure a comfortable ride, whilst removing enough to allow it to drop as far as is needed. Also, you need to ensure that sufficient is left in whatever downtube arrangement you have when the seat is at its highest point to safely hold the seatpost. HTH but if it don't make much sense, apologies, feeling a bit fluffy headed this a.m. Cheers, Dave.
It does help and it does make sense - thanks Dave!
Cos I've got a full-suspension bike the downtube is only 160mm long. I'm looking for a longer seatpost & was a bit concerned (probably unnecessarily) about any unwanted seatpost length sticking outa the bottom & fouling the suspension if/when going over big bumps.
I couldn't think of any reason why a seatpost couldn't be cut down though it would theoretically affect the minimum insertion mark I guess (but not in a practical way - I intend to more or less fill up the 160mm downtube!).
Thanks again!
--
John Latter
Model of an Internal Evolutionary Mechanism (based on an extension to homeostasis) linking Stationary-Phase Mutations to the Baldwin Effect. members.aol.comTEM.htmlOpen ↗
I'm currrently looking for a longer 28.6 diameter seatpost than the one I have now. I've seen one which is 410mm in length which will definately be too long - is it 'acceptable' to cut the length down in such instances? (btw I have a full-suspension bike)
It is, but make a note of height of min insertion mark from bottom, and preferably make a new mark on seatpost* in case it's ever raised** or used on another bike. Minimum insertion is a fixed length for that seatpost, not proportinate to total length.
"John Latter" <[email hidden]> wrote in message "]news:[email hidden]...
Quoted message said:
\(t'other\) Dave' no- said:
"John Latter" <[email hidden]> wrote in message "]news:[email hidden]...
Quoted message said:
Hi,
I'm currrently looking for a longer 28.6 diameter seatpost than the one I have now. I've seen one which is 410mm in length which will definately be too long - is it 'acceptable' to cut the length down in such instances? (btw I have a full-suspension bike)
Regards,
--
John Latter
Model of an Internal Evolutionary Mechanism (based on an extension to
homeostasis) linking Stationary-Phase Mutations to the Baldwin Effect.
I cut mine down to allow the seat to be dropped to an 'acceptable' level
for
Quoted message said:
Quoted message said:
singletrack riding, with no apparent bad side effects. Obviously, if
you're
Quoted message said:
Quoted message said:
doing it for a similar reason, ensure you hit the happy medium of leaving enough to ensure a comfortable ride, whilst removing enough to allow it
to
Quoted message said:
Quoted message said:
drop as far as is needed. Also, you need to ensure that sufficient is
left
Quoted message said:
Quoted message said:
in whatever downtube arrangement you have when the seat is at its highest point to safely hold the seatpost. HTH but if it don't make much sense, apologies, feeling a bit fluffy
headed
Quoted message said:
Quoted message said:
this a.m. Cheers, Dave.
It does help and it does make sense - thanks Dave!
Cos I've got a full-suspension bike the downtube is only 160mm long. I'm looking for a longer seatpost & was a bit concerned (probably unnecessarily) about any unwanted seatpost length sticking outa the bottom & fouling the suspension if/when going over big bumps.
I couldn't think of any reason why a seatpost couldn't be cut down though it would theoretically affect the minimum insertion mark I guess (but not in a practical way - I intend to more or less fill up the 160mm downtube!).
Thanks again!
--
John Latter
Model of an Internal Evolutionary Mechanism (based on an extension to
homeostasis) linking Stationary-Phase Mutations to the Baldwin Effect.
No problem....glad it made sense ;-) One thing to be wary of is not locking off your quick release that holds the seat post in properly when moving it up and down. I did this once in the rush to move from single track mode to fireroad mode and after a few hundred yards the seatpost dropped through with my full weight on it and took a chunk out of the rear suspension unit (ouch!!)...it ain't exploded yet but I guess it could..at some point. If you saw the seatpost down, smooth the sawn end off, just in case ;-) Cheers, Dave.
"Pete Biggs" <[email hidden]> wrote in message "]news:[email hidden]...
Quoted message said:
Paul said:
I would imagine it's ok with Ali' titainium but I wouldn't cut carbon fibre posts down.
Why not?
Carbon fork steerer tubes are cut down.
~PB
Only with dedicated blades and they are designed to be cut. It's quite possible that with a fibrous material you could be cutting into a vital part of the design. All I mean is without someone being able to say for certain that it would be ok with a paticular post, I wouldn't cut it.
Paul
--- Outgoing mail is certified Virus Free. Checked by AVG anti- virus system (grisoft.comgrisoft.comOpen ↗). Version: 6.0.651 / Virus Database: 417 - Release Date: 05/04/2004
I would imagine it's ok with Ali' titainium but I wouldn't cut carbon fibre posts down.
Why not?
Carbon fork steerer tubes are cut down.
Only with dedicated blades and they are designed to be cut. It's quite possible that with a fibrous material you could be cutting into a vital part of the design. All I mean is without someone being able to say for certain that it would be ok with a paticular post, I wouldn't cut it.
Only with dedicated blades and they are designed to be cut. It's quite possible that with a fibrous material you could be cutting into a vital part of the design. All I mean is without someone being able to say for certain that it would be ok with a paticular post, I wouldn't cut it.
Oh FFS don't be such an ass. The end of the post quite possibly isn't even _touching_ anything and is certainly not carrying any load.
James -- If I have seen further than others, it is by treading on the toes of giants. ne.jphomeOpen ↗
I'm currently looking for a longer 28.6 diameter seatpost than the one I have now. I've seen one which is 410mm in length which will definitely be too long - is it 'acceptable' to cut the length down in such instances? (btw I have a full-suspension bike)
Yes, as long as there's enough post in the tube to keep it secure and stop it levering out. It would depend on things I won't speculate on how much you can trim it, but should be the case that anything hanging out the bottom of the tube won't do anything useful for you.
Pete.
Thanks Pete - the downtube on my bike is 160mm so I intend cutting it off more or less flush with the bottom which'll be 'safer' than using the minimum insertion mark that I'm using at the moment.
I hope..
🙂
Regards,
--
John Latter
Model of an Internal Evolutionary Mechanism (based on an extension to homeostasis) linking Stationary-Phase Mutations to the Baldwin Effect. members.aol.comTEM.htmlOpen ↗
"John Latter" <[email hidden]> wrote in message "]news:[email hidden]...
Quoted message said:
\(t'other\) Dave said:
"John Latter" <[email hidden]> wrote in message "]news:[email hidden]... > Hi, > > I'm currrently looking for a longer 28.6 diameter > seatpost than the one I have now. I've seen one which > is 410mm in length which will definately be too long - > is it 'acceptable' to cut the length down in such > instances? (btw I have a full-suspension bike) > > Regards, > > -- > > John Latter > > Model of an Internal Evolutionary Mechanism (based on > an extension to homeostasis) linking Stationary-Phase Mutations to the Baldwin Effect. > members.aol.comTEM.htmlOpen ↗ > > 'Where Darwin meets Lamarck?' Discussion Egroup > groups.yahoo.comevomechOpen ↗
I cut mine down to allow the seat to be dropped to an 'acceptable' level
for
Quoted message said:
Quoted message said:
singletrack riding, with no apparent bad side effects. Obviously, if
you're
Quoted message said:
Quoted message said:
doing it for a similar reason, ensure you hit the happy medium of leaving enough to ensure a comfortable ride, whilst removing enough to allow it
to
Quoted message said:
Quoted message said:
drop as far as is needed. Also, you need to ensure that sufficient is
left
Quoted message said:
Quoted message said:
in whatever downtube arrangement you have when the seat is at its highest point to safely hold the seatpost. HTH but if it don't make much sense, apologies, feeling a bit fluffy
headed
Quoted message said:
Quoted message said:
this a.m. Cheers, Dave.
It does help and it does make sense - thanks Dave!
Cos I've got a full-suspension bike the downtube is only 160mm long. I'm looking for a longer seatpost & was a bit concerned (probably unnecessarily) about any unwanted seatpost length sticking outa the bottom & fouling the suspension if/when going over big bumps.
I couldn't think of any reason why a seatpost couldn't be cut down though it would theoretically affect the minimum insertion mark I guess (but not in a practical way - I intend to more or less fill up the 160mm downtube!).
Thanks again!
--
John Latter
Model of an Internal Evolutionary Mechanism (based on an extension to
homeostasis) linking Stationary-Phase Mutations to the Baldwin Effect.
No problem....glad it made sense ;-) One thing to be wary of is not locking off your quick release that holds the seat post in properly when moving it up and down. I did this once in the rush to move from single track mode to fireroad mode and after a few hundred yards the seatpost dropped through with my full weight on it and took a chunk out of the rear suspension unit (ouch!!)...it ain't exploded yet but I guess it could..at some point. If you saw the seatpost down, smooth the sawn end off, just in case ;-) Cheers, Dave.
I'll make sure I smooth the end off if I do saw it down - you were lucky you didn't hurt yourself as well as the bike! (I didn't know suspension units could explode either.. 'gulp'😉.
I have taken care to make sure the quick release is tightened properly (especially as I've never had this type of fitting before) and after reading your story I think I'll ALWAYS take care now! 🙂
Regards,
--
John Latter
Model of an Internal Evolutionary Mechanism (based on an extension to homeostasis) linking Stationary-Phase Mutations to the Baldwin Effect. members.aol.comTEM.htmlOpen ↗
> I would imagine it's ok with Ali' titainium but I > wouldn't cut carbon fibre posts down.
Why not?
Carbon fork steerer tubes are cut down.
Only with dedicated blades and they are designed to be cut. It's quite possible that with a fibrous material you could be cutting into a vital part of the design. All I mean is without someone being able to say for certain that it would be ok with a paticular post, I wouldn't cut it.
That's fair enough.
Scratch that, I've changed my mind back (after reading James's post)!
Should be no harm in cutting down a carbon post unless it's a design where you'd be inserting an inappropriate part of the post into the frame, which might be the case with some special aero posts for example. But that's really to do with how low the post can go rather than cutting material.
> >"John Latter" <[email hidden]> wrote in message >"]news:[email hidden]... >> Hi, >> >> I'm currrently looking for a longer 28.6 diameter >> seatpost than the one I have now. I've seen one >> which is 410mm in length which will definately be >> too long - is it 'acceptable' to cut the length down
in
Quoted message said:
Quoted message said:
Quoted message said:
>> such instances? (btw I have a full-suspension bike) >> >> Regards, >> >> -- >> >> John Latter >> >> Model of an Internal Evolutionary Mechanism (based >> on an extension
to
Quoted message said:
Quoted message said:
Quoted message said:
>homeostasis) linking Stationary-Phase Mutations to the >Baldwin Effect. >> members.aol.comTEM.htmlOpen ↗ >> >> 'Where Darwin meets Lamarck?' Discussion Egroup >> groups.yahoo.comevomechOpen ↗ > >I cut mine down to allow the seat to be dropped to an >'acceptable'
level
Quoted message said:
Quoted message said:
for
Quoted message said:
>singletrack riding, with no apparent bad side effects. >Obviously, if
you're
Quoted message said:
>doing it for a similar reason, ensure you hit the >happy medium of
leaving
Quoted message said:
Quoted message said:
Quoted message said:
>enough to ensure a comfortable ride, whilst removing >enough to allow
it
Quoted message said:
Quoted message said:
to
Quoted message said:
>drop as far as is needed. Also, you need to ensure >that sufficient is
left
Quoted message said:
>in whatever downtube arrangement you have when the >seat is at its
highest
Quoted message said:
Quoted message said:
Quoted message said:
>point to safely hold the seatpost. HTH but if it don't >make much sense, apologies, feeling a bit fluffy
headed
Quoted message said:
>this a.m. Cheers, Dave. >
It does help and it does make sense - thanks Dave!
Cos I've got a full-suspension bike the downtube is only 160mm long. I'm looking for a longer seatpost & was a bit concerned (probably unnecessarily) about any unwanted seatpost length sticking outa the bottom & fouling the suspension if/when going over big bumps.
I couldn't think of any reason why a seatpost couldn't be cut down though it would theoretically affect the minimum insertion mark I guess (but not in a practical way - I intend to more or less fill up the 160mm downtube!).
Thanks again!
--
John Latter
Model of an Internal Evolutionary Mechanism (based on an extension to
homeostasis) linking Stationary-Phase Mutations to the Baldwin Effect.
No problem....glad it made sense ;-) One thing to be wary of is not locking off your quick release that holds
the
Quoted message said:
Quoted message said:
seat post in properly when moving it up and down. I did this once in the rush to move from single track mode to fireroad mode and after a few
hundred
Quoted message said:
Quoted message said:
yards the seatpost dropped through with my full weight on it and took a chunk out of the rear suspension unit (ouch!!)...it ain't exploded yet
but I
Quoted message said:
Quoted message said:
guess it could..at some point. If you saw the seatpost down, smooth the
sawn
Quoted message said:
Quoted message said:
end off, just in case ;-) Cheers, Dave.
I'll make sure I smooth the end off if I do saw it down - you were lucky you didn't hurt yourself as well as the bike! (I didn't know suspension units could explode either.. 'gulp'😉.
<snip>
eerrrmm...I'm guessing it might but only after rather a large chunk was gouged out by the sharp seatpost after it fell through with my not inconsiderable bulk atop!!..after all, there is a fair bit of air pressure in there and I'd guess the walls of the shock aren't *that* thick... I don't think it's a regular occurrence and I'd bet it's never actually happened, but best to always look on the dark side, eh? ;-) (no, not 'bents!!) Dave.
I'll make sure I smooth the end off if I do saw it down
An extra finishing touch is to chamfer the end with a file so it's easier to insert into frame.
If not using a proper guide, marking with insulating tape makes it quite easy to saw it fairly square by hand. Works for me and I can't even cut a slice of bread straight :-)
I'm currrently looking for a longer 28.6 diameter seatpost than the one I have now. I've seen one which is 410mm in length which will definately be too long - is it 'acceptable' to cut the length down in such instances? (btw I have a full-suspension bike)
It is, but make a note of height of min insertion mark from bottom, and preferably make a new mark on seatpost* in case it's ever raised** or used on another bike. Minimum insertion is a fixed length for that seatpost, not proportinate to total length.
* Not a deep horizontal score mark. Paint?
** You might lend your bike to a taller person.
~PB
I had wondered what to do about that, its gonna be ok for me and I just idly thought "well throw it away when you get a new bike!".
--
John Latter
Model of an Internal Evolutionary Mechanism (based on an extension to homeostasis) linking Stationary-Phase Mutations to the Baldwin Effect. members.aol.comTEM.htmlOpen ↗
"John Latter" <[email hidden]> wrote in message "]news:[email hidden]...
Quoted message said:
\(t'other\) Dave said:
"John Latter" <[email hidden]> wrote in message "]news:[email hidden]... > On Wed, 21 Apr 2004 09:58:28 +0100, "\(t'other\) Dave" > <[email hidden]> wrote: > > > > >"John Latter" <[email hidden]> wrote in message > >"]news:[email hidden]... > >> Hi, > >> > >> I'm currrently looking for a longer 28.6 diameter > >> seatpost than the one I have now. I've seen one > >> which is 410mm in length which will definately be > >> too long - is it 'acceptable' to cut the length > >> down
in
Quoted message said:
Quoted message said:
> >> such instances? (btw I have a full-suspension bike) > >> > >> Regards, > >> > >> -- > >> > >> John Latter > >> > >> Model of an Internal Evolutionary Mechanism (based > >> on an extension
to
Quoted message said:
Quoted message said:
> >homeostasis) linking Stationary-Phase Mutations to > >the Baldwin Effect. > >> members.aol.comTEM.htmlOpen ↗ > >> > >> 'Where Darwin meets Lamarck?' Discussion Egroup > >> groups.yahoo.comevomechOpen ↗ > > > >I cut mine down to allow the seat to be dropped to an > >'acceptable'
level
Quoted message said:
Quoted message said:
for > >singletrack riding, with no apparent bad side > >effects. Obviously, if you're > >doing it for a similar reason, ensure you hit the > >happy medium of
leaving
Quoted message said:
Quoted message said:
> >enough to ensure a comfortable ride, whilst removing > >enough to allow
it
Quoted message said:
Quoted message said:
to > >drop as far as is needed. Also, you need to ensure > >that sufficient is left > >in whatever downtube arrangement you have when the > >seat is at its
highest
Quoted message said:
Quoted message said:
> >point to safely hold the seatpost. HTH but if it > >don't make much sense, apologies, feeling a bit > >fluffy headed > >this a.m. Cheers, Dave. > > > > It does help and it does make sense - thanks Dave! > > Cos I've got a full-suspension bike the downtube is > only 160mm long. I'm looking for a longer seatpost & > was a bit concerned (probably unnecessarily) about any > unwanted seatpost length sticking outa the bottom & > fouling the suspension if/when going over big bumps. > > I couldn't think of any reason why a seatpost couldn't > be cut down though it would theoretically affect the > minimum insertion mark I guess (but not in a practical > way - I intend to more or less fill up the 160mm > downtube!). > > Thanks again! > > -- > > John Latter > > Model of an Internal Evolutionary Mechanism (based on > an extension to homeostasis) linking Stationary-Phase Mutations to the Baldwin Effect. > members.aol.comTEM.htmlOpen ↗ > > 'Where Darwin meets Lamarck?' Discussion Egroup > groups.yahoo.comevomechOpen ↗
No problem....glad it made sense ;-) One thing to be wary of is not locking off your quick release that holds
the
Quoted message said:
Quoted message said:
seat post in properly when moving it up and down. I did this once in the rush to move from single track mode to fireroad mode and after a few
hundred
Quoted message said:
Quoted message said:
yards the seatpost dropped through with my full weight on it and took a chunk out of the rear suspension unit (ouch!!)...it ain't exploded yet
but I
Quoted message said:
Quoted message said:
guess it could..at some point. If you saw the seatpost down, smooth the
sawn
Quoted message said:
Quoted message said:
end off, just in case ;-) Cheers, Dave.
I'll make sure I smooth the end off if I do saw it down - you were lucky you didn't hurt yourself as well as the bike! (I didn't know suspension units could explode either.. 'gulp'😉.
<snip>
eerrrmm...I'm guessing it might but only after rather a large chunk was gouged out by the sharp seatpost after it fell through with my not inconsiderable bulk atop!!..after all, there is a fair bit of air pressure in there and I'd guess the walls of the shock aren't *that* thick... I don't think it's a regular occurrence and I'd bet it's never actually happened, but best to always look on the dark side, eh? ;-) (no, not 'bents!!) Dave.
Maybe we're talking about two different types of rear suspension Dave - all I've got is a big black spring which joins to some oversize tubes running down either side of the wheel.
On the other hand it is best to look on the dark side - I'll now presume the oversize joints are wafer thin, pressurized to within a millibar of exploding, and just waiting to be jolted by a piece of road grit that's got ideas above its station..
P'haps I ought to get a really l-o-n-g seatpost to keep me away from the BANG!
--
John Latter
Model of an Internal Evolutionary Mechanism (based on an extension to homeostasis) linking Stationary-Phase Mutations to the Baldwin Effect. members.aol.comTEM.htmlOpen ↗
I'll make sure I smooth the end off if I do saw it down
An extra finishing touch is to chamfer the end with a file so it's easier to insert into frame.
If not using a proper guide, marking with insulating tape makes it quite easy to saw it fairly square by hand. Works for me and I can't even cut a slice of bread straight :-)
~PB
Good ideas Pete - 'specially using insulating tape! ta 🙂
--
John Latter
Model of an Internal Evolutionary Mechanism (based on an extension to homeostasis) linking Stationary-Phase Mutations to the Baldwin Effect. members.aol.comTEM.htmlOpen ↗
I'm currrently looking for a longer 28.6 diameter seatpost than the one I have now. I've seen one which is 410mm in length which will definately be too long - is it 'acceptable' to cut the length down in such instances? (btw I have a full-suspension bike)
Yes. I do it to save weight. The post should always reach at least 1" below the bottom of the top tube on a conventional frame.
