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Old 04-13-11, 06:19 PM   #1
chagzuki
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Brompton aluminium telescopic seat post. . . steel upper?

I can't seem to find an aluminium top section to the telescopic post on sale; is it just the main post that's not steel?
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Old 04-13-11, 07:17 PM   #2
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Top part is usually aluminum. Calhoun's in MN has a different shim in their telescoping seat post ,
steel main section, upper is 27.2 so you can use a nice integrated saddle clamp type,
though they will include a budget one.. Kalloy for either , I expect.
http://www.calhouncycle.com/productc...&idproduct=873

another shim with an ID of 1" would let one use a chromoly plain seatpost
such as sold under Red Line brand..

Might still be some Ti main section posts, around..
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Old 04-14-11, 07:14 AM   #3
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Looks like the official Brompton version does use a steel top post. The parts are listed here and there's no alloy version:

http://www.brompton.co.uk/technical/...egory.asp?q=F3

The top section doesn't look flared either to prevent it from being easily removed, i.e. stolen.
Given all that there doesn't seem any point in using Brompton's own brand version.
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Old 04-14-11, 09:30 AM   #4
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QSPTTOP is aluminum ,QSPTS , the larger bottom tube, is steel [or titanium]

with the rubber Bung in the bottom and a plug in the open upper end
of the 2 seat post parts.
a modest bit of cleverness , you can fix a piece of cable inside the seat post
anchored in the end of each.

Of course you can always just fold the bike up and bring it inside.
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Old 04-14-11, 09:39 AM   #5
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I think the 2011 X code light weight Brommy versions have the QSPT
A,for aluminum now
rather than Ti ... spotty sourcing, I hear.
But I don't own one. so Im not sure .

another clever option : a flat-washer that is smaller than the ID of the tube ,
but larger than the ID of the bushing at the top of the tube ,
and having that fixed in the bottom of the upper section of the combination.
will stop it from pulling out.

Last edited by fietsbob; 04-14-11 at 09:53 AM.
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Old 04-14-11, 09:43 AM   #6
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Ah, so the top is aluminium on the standard telescopic seatpost? Weird as it only costs 6 whereas the standard length aluminium seat post is 50.
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Old 04-14-11, 09:51 AM   #7
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you mean QSP6XL? its a whole post.32mm diameter, made for them .
QSPTS is mass produced. they just buy lots of them.
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Old 04-14-11, 09:59 AM   #8
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Aha. . . I think I'm best off sticking with my homemade telescopic seat post. Maybe. probably.
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Old 04-14-11, 10:02 AM   #9
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Do you know the length and OD of QSPTTOP?
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Old 04-14-11, 11:10 AM   #10
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No, ask : Andrew Finkill <andrew.finkill@brompton.co.uk>

Technical Support guy





Brompton Bicycle Ltd
Kew Bridge DC
Lionel Road South
Brentford
Middlesex TW8 9QR

Direct: +44 (0)20 8232 3558
Tel: +44 (0)20 8232 8484
Fax: +44 (0)20 8232 8181
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