Seized seat post clamp: advice?

[Simon Brooke]

I've just acquired myself a Klein Mantra frame - to be
precise, this one <URL:http://cgi.ebay.co.uk/ws/eBayISAPI.d-
ll?ViewItem&item=3667944572> to experiment with. I've got a
few wee problems I need to sort before I can get it going.

The most serious is that the seat post clamp has an allen
bolt rather than a quick release, and at some point someone
has used the wrong size allen key and rounded off the flats.
The bolt is also jammed and I can't turn it. I'm tempted to
take an angle grinder and slice through the bolt, but I
can't tell whether the seat tube clamp is integral with the
frame or not. If it is I would look bloody stupid because I
would then have a seized thread in there I would have no way
of getting out. Does anyone know for a fact whether the seat
tube clamp on a Mantra is integral?

--
[email protected] (Simon Brooke)
http://www.jasmine.org.uk/~simon/

;; Life would be much easier if I had the
source code.

 

[Doki]

"Simon Brooke" <[email protected]> wrote in message
news:[email protected]...
> I've just acquired myself a Klein Mantra frame - to be
> precise, this one <URL:http://cgi.ebay.co.uk/ws/eBayISA-
> PI.dll?ViewItem&item=3667944572> to experiment with.
> I've got a few wee problems I need to sort before I can
> get it going.
>
> The most serious is that the seat post clamp has an allen
> bolt rather than a quick release, and at some point
> someone has used the wrong size allen key and rounded off
> the flats. The bolt is also jammed and I can't turn it.
> I'm tempted to take an angle grinder and slice through the
> bolt, but I can't tell whether the seat tube clamp is
> integral with the frame or not. If it is I would look
> bloody stupid because I would then have a seized thread in
> there I would have no way of getting out. Does anyone know
> for a fact whether the seat tube clamp on a Mantra is
> integral?

I'd be tempted to cover the whole thing in a liberal
quantity of WD40, plus gas or similar, then take a hacksaw
to it and cut a slot in the end of the allen bolt, then
unscrew it with a big screwdriver. If you're feeling flush
you could do it with dremel cut off disks, but they don't
last long on anything very heavy. Did a similar thing on a
much smaller scale with a rounded aluminium screw on some
shifters t'tother day and it works fine.

 

[Sandy Morton]

In article <[email protected]>, Doki
<[email protected]> wrote:
> I'd be tempted to cover the whole thing in a liberal
> quantity of WD40, plus gas or similar, then take a hacksaw
> to it and cut a slot in the end of the allen bolt, then
> unscrew it with a big screwdriver.

Plus gas then the angle grinder to cut a slot and then a
great big screwdriver should work.

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

 

[Graham Bowers]

Simon Brooke wrote:

> I've just acquired myself a Klein Mantra frame - to be
> precise, this one <URL:http://cgi.ebay.co.uk/ws/eBayISA-
> PI.dll?ViewItem&item=3667944572> to experiment with.
> I've got a few wee problems I need to sort before I can
> get it going.
>
> The most serious is that the seat post clamp has an allen
> bolt rather than a quick release, and at some point
> someone has used the wrong size allen key and rounded off
> the flats. The bolt is also jammed and I can't turn it.
> I'm tempted to take an angle grinder and slice through the
> bolt, but I can't tell whether the seat tube clamp is
> integral with the frame or not. If it is I would look
> bloody stupid because I would then have a seized thread in
> there I would have no way of getting out. Does anyone know
> for a fact whether the seat tube clamp on a Mantra is
> integral?
>
Why not email Klein if nothing shows up here? I have a pal
who had one, I'll email him. Cheers Graham

 

[Paul Moss]

"Doki" <[email protected]> wrote in message
news:[email protected]...
>
>
> Simon Brooke wrote:
> > in message <[email protected]>,
> > Doki ('[email protected]') wrote:
> >
> >>
> >> "Simon Brooke" <[email protected]> wrote in message
> >> news:[email protected]...
> >>>
> >>> The most serious is that the seat post clamp has an
> >>> allen bolt rather than a quick release, and at some
> >>> point someone has used the
..............
........ Snipped
>
> Crikey. I'd be tempted to ask in uk.rec.cars.maintenance,
> as there are generally a fair few questions there about
> getting siezed studs out of engines and so on. There are
> special tools you can use, which AFAIK are a special drill
> bits which drill in normally, then dig in when you reverse
the
> drill, however they're generally seen as being useless on
> a lot of car stuff, but it's likely a bike seatpost clamp
> was torqued up with an allen key rather than a foot long
> ratchet.

Stud Extractor. It looks a bit like a square pyramid but
very thin and tall. About two or three inches long. During
manufacture it is twisted into a lefthand spiral.

The bolt must be drilled down the middle and then the
extractor is screwed into the hole until it jams in tightly.
Once it jams in you keep turning it and being a LH thread it
should unscrew the bolt. If it snaps then you will really
have a problem as it is too hard to drill with ordinary
tools. Paul.

 

[Doki]

Paul Moss wrote:

> Stud Extractor. It looks a bit like a square pyramid but
> very thin and tall. About two or three inches long. During
> manufacture it is twisted into a lefthand spiral.
>
> The bolt must be drilled down the middle and then the
> extractor is screwed into the hole until it jams in
> tightly. Once it jams in you keep turning it and being a
> LH thread it should unscrew the bolt. If it snaps then you
> will really have a problem as it is too hard to drill with
> ordinary tools.

That's the one. My understanding is that they snap often
enough to make them a bad risk when you're faffing around
with car stuff. Whether bike stuff has less time to corrode
or gets torqued up less, I've no idea.