Early GT Info

Welcome to the early GT technical site for mainly 1980 through 1983 models.

As an avid early GT collector in search of all colors and sizes of 80-83 GT's, I have researched extensively what was available back in that time, plus some 70s. I will provide what I have found, and ask for what I don't have.

This site will be a constant work in progress. Going to start with the size guide. I have had most sizes in my collection, and measured using the crude 'Crescent wrench over the tubes and measuring the jaw's spread' since I do not have caliper gages. Most length mesures are done from center to center in inches.

Here is the spec diagram for the following measures:

They started actually stamping the size on the dropout with the serial number in mid 82.

Frame Stamp / Size	Top Tube	Down Tube	Height	Rear Stay	Top Tube Diameter	Down Tube Diameter
16 - Pit bike	16.25	16.75	7.25	15	1.25	1.25
JR - Junior / Mini (mostly Euro bb's)	17	17.5	8.5	16	1.125	.875
1 - Standard/Expert w/ Euro bb	17	17.5	8.5	16.5	1.25	Pre 82 -1.00 / Late 82 - 1.25
2 - Standard/Expert w/ American bb	17	17.5	8.5	16.5	1.25	Pre 82 -1.00 / Late 82 - 1.25
3 - Pro w/ Euro bb	18.5	19.25	8.5	16	1.25	Pre 82 -1.125 / Late 82 - 1.25
4 - Pro w/ American bb	18.5	19.25	8.5	16	1.25	Pre 82 -1.125 / Late 82 - 1.25
4L - Pro XL w/ American bb (late 83ish)*	19.5	20.50	8.5	16	1.25	1.25
24 - Cruiser	20.25	22.125	13.00	19.5	1.25	1.25
26 - Cruiser	22.125	24	13.25	19.5	1.25	1.25
*Actual measures not validated. Best Guess
Forks
Mini			10.5		.875
Pro			11		1.00

Here are some early advertisements showing colors and sizes. Standard colors were Red, Blue, Black and the most commonly seen Chrome.

I had a question about what a GT-3 was in the ad on the left. So, I asked the man himself.

I have since found and acquired two GT-3s, shown below in the bikes section, and know of another two in Massachusets and Wisconsin.

The rear of all models 83 and earlier have a flat, unstamped end of the top tube, like this.

The Nora Cup designation

In November of 82, GT won the Nora Cup for best manufacturer. So, for 83, they could run the Nora Cup decal on all frames as the 82 winner. Decal says 82.

There was never a Nora Cup model. Stating you have a Nora Cup bike is an incorrect description. If you have to mention it, just say Nora Cup winner year/era!

Correct decal

Serial Number Info

The standard serial number, found on the inner drive side dropout, will be as follows: Month, Year, Production number, and from four to eight numbers.

August 81 January 81

May 82 (about the time size stamps started as well)

October 83 January 82 (rare 4 digit)

There are some oddities, as seen on this 80 Pro, 0 at the beginning

One of the most rare frames is the 83 Pro Long. Has a 19.5" top tube and a L4 stamp

Here's a partial group shot of some of the bikes I've had.


1980 Standard/Expert w/ Euro bb (GT-1) - OG Red	1980 Pro W/ American bb (GT-4) - OG Red	1981 Pro w/ Euro bb (GT-3) - Chrome
1981 Pro w/ American bb (GT-4) - OG Blue	1981 Cruiser 24	1981 Cruiser 26
1982 Pro w/ Euro bb (GT-3) - Custom white	83 GT Jr / Mini	83 Pro (GT-4) - Black Chrome
	83 Pit bike - 16"	83 Expert (GT-2) - Black Chrome



	I am also a Skyway Tuff Wheel enthusiast.

This is an individual website. Some pictures sourced from images found on the internet.