GT Xizang Serial number thread

Here is mine (1996?):

Xizang SN / Frame Attributes

This is a great thread idea, but I think all this SN info is not very useful unless we associate it with specific, identifying attributes. Here are some ideas for future (and previous) posts (edited per gm input):

• SN / MADE IN USA Stamping - Serial numbers and/or the alpha prefixes may be a key, and for some reason, some frames do not have MADE IN USA stamped in the BB shell.
  Seat Tube Insert/Shim - Likely existed on earlier models only.
  Head Tube Shape - Some 'Zangs (pre-1996 I believe) have a slightly thicker collar at the top and bottom of the headtube. Later models are straight or have thickness changes on the inside of the tube.
  Rear Brake Hanger - Newer models (starting perhaps 1996) have the ring welded to the seattube, earlier models have a welded cable stop.
  Rear Dropouts - GT logos, plain, removable, etc. Not even sure how many options there are.
  Cable Routing - Someone mentioned internal routing on a very early model. Different types or locations of barrels.
  Stickers - Obviously not a good identifier unless there is some reason to believe they are original.
  Photo - A simple photo of the frame could help with other attributes that I didn't think of here.

There may be others, but I think it's a good start.

My Xizang details...

SN / MADE IN USA Stamping - GTX96110 (just eight prior to MerlinBoy's), No USA stamping.
Seat Tube Insert/Shim - No.
Head Tube Shape - Straight outside.
Rear Brake Hanger - The ring.
Rear Dropouts - GT logos, Ti.
Cable Routing - No internal routing, typical one sided barrels.
Stickers - Red/Black/Yellow, GT on the downtube, questionably original.

SN Theory

It seems there is a reasonable theory surfacing here for Xizang serial numbers:

TTN-prefix serial numbers are of format (TTN?????). These may be the early Maurice Lavoie builds, Whistler BC, Canada.

G-prefix serial numbers are all GAABBB, where AA is the frame size and BBB is the production sequence number of the frame, perhaps total for that size. Example: G-19177

GT-prefix serial numbers are either another year (eg: eventually they would have made 999 of a given size and then maybe went to the GT prefix) or a different manufacturing site than the G-sn's. Example: GT19020

GTX-prefix serial numbers are GTXCCDDD, where CC is the last two digits of the year, and DDD is the production sequence for that year - a much better SN format. Example: GTX96110

KB-prefix serial numbers are KBEEFFFF GG, where EE is the last two digits of the year, FFFF is ???, and GG is the frame size. Example: KB995005 19

G and GT serial numbers are the only ones stamped "MADE IN USA". Why they would not have stamped "MADE IN USA" if in fact all the Xizang frames were made in the USA (except perhaps the TTN-numbers) is a mystery. Maybe they just thought it was too obvious to explicitly state.

Re: Xizang SN / Frame Attributes

micstew":2s9k91jk said:

This is a great thread idea, but I think all this SN info is not very useful unless we associate it with specific, identifying attributes. Here are some ideas for future (and previous) posts:

• SN / MADE IN USA Stamping - Serial numbers and/or the alpha prefixes may be a key, and for some reason, some frames do not have MADE IN USA stamped in the BB shell.
  Bike Size & Head Tube Length - I believe head tubes are shorter on newer years given size on older frames. Not sure what the year change was, but I have read that early models were not suspension corrected.
  Head Tube Shape - Some 'Zangs (pre-1996 I believe) have a slightly thicker collar at the top and bottom of the headtube. Later models are straight.
  Rear Brake Hanger - Newer models (starting perhaps 1996) have the ring welded to the seattube, earlier models have a welded cable stop.
  Rear Dropouts - GT logos, plain, removable, etc. Not even sure how many options there are.
  Cable Routing - Someone mentioned internal routing on a very early model. Different types or locations of barrels.
  Stickers - Obviously not a good identifier unless there is some reason to believe they are original.
  Photo - A simple photo of the frame could help with other attributes that I didn't think of here.

There may be others, but I think it's a good start.

Click to expand...

May want to add seat tube insert/shim or not to your list. I think on the head tube machining/collars they just changed it from external in the early years to internal in the later years. I think the head tube lengths have been very consistent on the 25 or so that I've had through my hands in the last couple years.
Other than a half degree change in the head angle from the first couple years to all the later years there has been little or no change in the life of the Xizang in terms of angles, suspension adjustments or TTL's. I've put all year frames post 91 up against my 91 and they're all so close you'd need a good protractor to tell/find any difference at all.

The 1991 model Xizang had internal cable routing. Cable entered on the left side of the head tube and exited along the bottom of the top tube where the seat stays come together. I've also seen a frame or two that had internal routing but the tig welding was visible on the outside of the whole opening. This 1991 model finish is truly amazing. Very clean. The hole looks large compared to the cable but that's because I'm running 5mm housing now and back when the frame was new the standard was 6mm with the 1.7mm braided innerwires. The rear dropouts were clean and simple back then as well look to be 6mm thick and laser cut were probably even 6/4 material. 1991 model also had a 31.8mm seat tube diameter but tool a 29.4mm seat post. I've run 29.4's and shimmed 27.2's in this frame over the years and they all worked just fine. Real Ti brazed on water bottle bosses on the 91 model also. No cheap rivnut bottle bosses like the later frames.

Couple more to add:
18" 1998 Xizang....G18561

And a 18" 1995 Xizang......KB695004

Yet another....this one a 1998 model and the last of my current inventory.

Mine - 18" 1998

Frame number is G18631. Stamped MADE IN USA.

Original Red/Yellow/Purple/White decals

Forged GT logo dropouts

Welded loop canti' hanger mount.