Frame Identification Game
#1
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Frame Identification Game (1990's Giant Allegre)
I know for someone this be a very easy game, but I am interested in learning more about frame identification in general.
Clues:
Clues:
- Serial Number running parallel to frame is probably '6M019350' although it has been painted to make this much more difficult to decipher
- Bottom bracket also marked with 'CB' in the Center
- Under top tube at lug marking 'G2'
- 'Swooped' at tire on front steel fork
- Vertical Rear dropout
- Downtube stops
Last edited by kansascity; 02-21-21 at 05:38 PM.
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When I saw that cluster, first thing I thought was Trek also, but I feel like some expected cues aren't there.
Have you run a black crayon along the BB shell to help highlight the "50" or whatever mid-shell, or the number off to the side?
Have you run a black crayon along the BB shell to help highlight the "50" or whatever mid-shell, or the number off to the side?
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#4
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steerer appears to exhibit internal splines/"rifling"
how many are there?
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steerer appears to exhibit internal splines/"rifling"
how many are there?
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I don't see any splines/rifling. It looks like there are four blocks that cast into the crown to act as a seat for the steerer tube insertion during fork manufacture..
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I wonder can we draw @JohnDThompson
into this as the Trek expert? I agree the socketed stay caps/seat lug looks Trek-ish but that fork does not (to me, anyhow). And OFTEN you'd see the Trek logo cast-in to whatever the investment-cast piece in question (also not here)
into this as the Trek expert? I agree the socketed stay caps/seat lug looks Trek-ish but that fork does not (to me, anyhow). And OFTEN you'd see the Trek logo cast-in to whatever the investment-cast piece in question (also not here)
Last edited by unworthy1; 02-17-21 at 06:22 PM.
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I wonder can we draw @JohnDThompson
into this as the Trek expert? I agree the socketed stay caps/seat lug looks Trek-ish but that fork does not (to me, anyhow). And OFTEN you'd see the Trek logo cast-in to whatever the investment-cast piece in question (also not here)
into this as the Trek expert? I agree the socketed stay caps/seat lug looks Trek-ish but that fork does not (to me, anyhow). And OFTEN you'd see the Trek logo cast-in to whatever the investment-cast piece in question (also not here)
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May want to spend some time in this thread for other samples. There are a couple other fastback stays threads I've seen.
https://www.bikeforums.net/classic-v...eat-stays.html
https://www.bikeforums.net/classic-v...eat-stays.html
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#9
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Last edited by kansascity; 02-20-21 at 09:35 PM.
#10
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Took the fork out this morning, but it did not provide any more markings.
What would the shape of this fork be called?
What would the shape of this fork be called?
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OK, revised GM0 prefix for the serial number makes it consistent with Giant mid-1990 manufacture and the frame features match their Allegre model.
Last edited by T-Mar; 02-21-21 at 08:51 AM. Reason: added photo
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I do have price lists for 1990 and 1991 and a catalogue for 1992. In 1990 the Allegre was 2nd in a line of six road models. It cost $499-$550 US MSRP and was spec'd with SunTour GPX. For 1991 the component group was switched to Shimano RX100. 1992 was also spec'd with RX100 and the frame appears identical to 1990 except for a more elaborate paint finish.
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While it looks similar, Unicrown forks use blades that are attached directly to the steering tube, eliminating the traditional crown. They are typically lighter, more rigid and less expensive than a fork with a traditional crown. Generally, they are TIG welded and the weld beads are plainly visible. The subject fork uses an investment cast crown. While I'm not positive, I believe this one is proprietary to Giant.
Personally, I just generically refer to it an an aero(dynamic) crown, as it is sheltered almost entirely behind the brake caliper with little area directly exposed to the airflow. Giant's literature calls it a "flat side, investment cast crown".
Personally, I just generically refer to it an an aero(dynamic) crown, as it is sheltered almost entirely behind the brake caliper with little area directly exposed to the airflow. Giant's literature calls it a "flat side, investment cast crown".
Last edited by T-Mar; 02-22-21 at 06:09 AM.
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While it looks similar, Unicrown forks use blades that are attached directly to the steering tube, eliminating the traditional crown. They are typically lighter, more rigid and less expensive than a fork with a traditional crown. Generally, they are TIG welded and the weld beads are plainly visible. The subject fork uses an investment cast crown. While I'm not positive, I believe this one is proprietary to Giant.
Personally, I just generically refer to it an an aero(dynamic) crown, as it is sheltered almost entirely behind the brake caliper with little area directly exposed to the airflow. Giant's literature calls it a "flat side, investment cast crown".
Personally, I just generically refer to it an an aero(dynamic) crown, as it is sheltered almost entirely behind the brake caliper with little area directly exposed to the airflow. Giant's literature calls it a "flat side, investment cast crown".
had to scroll back up to look really closely at that one. I now see the weirdness on the inside and lack of apparent weld, plus the round-out on the inside. Glad to hear it's apparently a one-off, I've definitely never seen anything quite like it from the inside view.
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