Here is an email i got from an actual employee of gt.
Gt bike serial number.
I just received my 2016 specialized dolce elite and i just wanted to thank you for a great transaction.
Gt bicycles remains true to sharing the stoke on two wheels which the brand was founded on because after all you can t.
Since 1972 gt bicycles has proudly been developing bikes for every type of rider with a consistent mission.
Gt serial numbers are usually found stamped on the bottom of the bottom bracket of your bmx.
The next part of the serial number is eight numeric digits.
Okay fine so maybe there are a few bikes without serial numbers but this is rare and typical only on hand made bikes or really old bicycles.
Lifetime of the original owner.
Frames excluding those listed below.
Frames of gravity freeride downhill dirt jump and other astm category five bicycles.
If the bike frame was manufactured at the santa ana ca facility the first three or four digits of the serial number should be letters abbreviating the model or size of the frame such as xl xxl cr24 or something like that.
This is not always the case and there will be some bikes that do not fit into this formula.
Vintage and older gt bikes may have serial numbers placed on other areas of the frame such as the seat stays next to the rear dropouts or the head badge.
In this picture 200910427 2a is a manufacturer number and not a serial number.
However to make bikes as easy as possible to find feel free to enter all numbers you encounter.
That mission is the same reason everybody throws a leg over their very first bike pure fun plain and simple.
For mid school gt bmx bikes built in taiwan through most of the 90 s with a serial number that begins with 4 letters before the series of numbers.