Here is an email i got from an actual employee of gt.
Gt bike serial number.
Gt bicycles remains true to sharing the stoke on two wheels which the brand was founded on because after all you can t.
Modern gt bikes feature the bicycle s serial number on the underside of the frame and will be accompanied by a bar code.
This is the fourth bike i have bought from your company and every transaction has been excellent and every bike has been as good or better than described.
That mission is the same reason everybody throws a leg over their very first bike pure fun plain and simple.
This is not always the case and there will be some bikes that do not fit into this formula.
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.
However to make bikes as easy as possible to find feel free to enter all numbers you encounter.
Since 1972 gt bicycles has proudly been developing bikes for every type of rider with a consistent mission.
The next part of the serial number is eight numeric digits.
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.
Frames of gravity freeride downhill dirt jump and other astm category five bicycles.
Three years from original retail purchase.
Frames excluding those listed below.
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.
Gt serial numbers are usually found stamped on the bottom of the bottom bracket of your bmx.
Lifetime of the original owner.