Help With GT Aero / TT Frame: Funky Seatpost!



S

spincircles

Guest
I'd really appreciate some help with a problem I'm having in getting a
seat post to fit a GT time trial frame.

It looks pretty exotic. I suspect that if you've seen one of these,
the details below were interesting enough to be able to recall. If
you've never seen one, I'd bet that I'd have to do a whole lot more
writing to really describe this frame correctly.

Description of what I have to work with here:
Might be a pre-curser to the GT Vengeance, or perhaps is GT vengeance
frame. Looks a bit like the 96 Olympic superbike 1 frames that(IIRC)
were used to rough out the positions on our olympic athletes before the
full-tilt superbikes were made for them. Maybe it IS a SB1 (?) All
aluminum. It has a teardrop down and seat tube. The rear wheel fits
into a cutout in the curved seat tube. The faired seat tube actually
extends below the bottom bracket, kind of like a little hook to allow
the wheelremian faired below the BB. The top tube is round
(traditional). The rear triangle is all bladed alluminum. Rear drops
face rear (like a track bike). It has a rear der hanger that is not
replaceable. The rear drops and fork ends accept standard road hubs
with standard width axles.


It arrived (used) without a seatpost, which was (from what I've
gathered) orignally a funky looking post with a built on fairing. It
originally had a small bar that fit into the leading edge through which
two bolts extended to somehow either secure a fairing or a seatpost, or
both (If the fairing was an integral part of he seatpost). The two
holes in the front, leading edge of the seat tube are present. They
are not tapped or reniforced in any way.


The tube inside the faired-out seat tube is very skinny (I'd guess
around 25.0) and this seat tube has the end of the top tube crudely
poking into it at the junction in such a way as to prevent a seat post
from dropping below the seat / top tube junction. That is, the bottom
of a seatpost slides down the tube to rest on top of the top tube
intrusion.

There is no pinch bolt to secure a seatpost.

It takes two 700c wheels.

I had the assumption that I could fabricate what I needed to get a
faired seatpost to be fitted. Now that I've looked at it for a while,
I'm not sure how to proceed.

The Questions:

-What model/frame frame is this likely to be?

-Should the seatpost be inserted until it bottoms out on the intruding
top tube, then somehow secured with two horizontal bolts? Some other
arrangement? What would work?

What should I NOT do, so as to avoid damage to the frame?

Sources for original parts?


Thanks,
Pat Smith
 
On 20 Jun 2005 19:40:16 -0700, "spincircles"
<[email protected]> wrote:


>
>
>The tube inside the faired-out seat tube is very skinny (I'd guess
>around 25.0) and this seat tube has the end of the top tube crudely
>poking into it at the junction in such a way as to prevent a seat post
>from dropping below the seat / top tube junction. That is, the bottom
>of a seatpost slides down the tube to rest on top of the top tube
>intrusion.
>
>There is no pinch bolt to secure a seatpost.
>
>It takes two 700c wheels.
>
>I had the assumption that I could fabricate what I needed to get a
>faired seatpost to be fitted. Now that I've looked at it for a while,
>I'm not sure how to proceed.
>
>The Questions:
>
>-What model/frame frame is this likely to be?
>
>-Should the seatpost be inserted until it bottoms out on the intruding
>top tube, then somehow secured with two horizontal bolts? Some other
>arrangement? What would work?
>
>What should I NOT do, so as to avoid damage to the frame?
>
>Sources for original parts?
>
>
>Thanks,
>Pat Smith


Hi, I recently saw a bike like you describe, for sale on Ebay, it had
two different height fairings, that came with it. Maybe do an Ebay
search, in completed sales, to get a better idea of what you need. The
guy had a lot of pics.

Good luck.


Life is Good!
Jeff
 
It might be a GT Edge. If I remember that far back, there was a clamp
assembly that fit onto the top of the egg-shaped seat post.

Your best bet is to search out a GT dealer that's been around for 10-15
years. They may remember (but the Edge, and all the models you list,
were pretty darned rare). They might even have one in the bin of
assorted junk that always seems to accumulate.