here is an email I got from an actual employee of GT.:
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.
The next part of the serial number is eight numeric digits. The first four numbers should be a two digit month followed by a two digit year.
The last four digits are the serialization digits 0000 to 9999 depending on what number the frame was of the years production.
If the frame was made overseas in Taiwan, it gets more complicated. If the number starts with a K, the frame was made by Kinesis.
That's the only one I remember off the top of my head. There were at least four companies in Taiwan that made the GT lines :
Robinson, Dyno, Powerlite and Auburn included)
The first digit would be a letter designating the factory that made the frame. There might also be a second letter digit specifying the factory
that assembled the bike, if applicable. The model and year of production was also coded by a letter, so you won't be able to spot a two digit month
and two digit year.
Before I left, I was writing a specification to standardize all of the serial numbers because GT was starting to send most of its US
production to other US fabrication shops.
The information might also come in handy for deciphering other makes because the factories in Taiwan make bikes for a lot of different companies.
I am tinkering around with the idea of starting to make my own frames, kind of on a "one-off" basis. I am also teaching welding at
a local community college.
By the way, did I tell you that the guy ran GT's in house fabrication for the last ten years (he recently retired) was none other than Gilbert Axt.
Who? Do you remember Race, Inc.? That was Gilbert.
He also did the original PK Ripper for SE Racing. History, man.
It might be a really cool thing if I can track down Gilbert now and interview him for you.
THAT is the kind of stuff that belongs in the BMX Museum!
Later. I'll write you when I get a chance. Dan Garcia
and here is the updates, thanks to love thegoose! (Michael S)
well we get a good bit of gt serials that could be identified by the owner, if they only had the tips that some of us have learned,
so i will post what i know, and anyone with more knowledge can add to it..so here we go.
here is an example to go by. on the dropout you have "M1" followed by "08922198"..this one is simple.
M1 stands for "mach one" that is your model gt.
it can also be a "I" for interceptor and so on.
next on the serial is "0892" this is easy to decode too,
08 means 8th month, which would be august.
then you have "92" next in the lineup, this would be 1992
the last 4 digits, are your build number, this one would be the 2,198th one built.
Here is another example. if your serial is KGCG2297 this one gets a little complicated. but still easy once you learn the code to it.
the first letter is who made the frame itself, in this case it would be "Kenisis", an overseas company.
this could be replaced by another letter but at least we know what that one is there for.
next is the letter "G"..this isnt always there, but if so, this is where it was assembled,
(ever notice the built in usa sticker on your gt or dyno?) this is what that letter is there for. it wasnt made here, but was built here.
next is the letter "C"..C is the 3rd letter in the alphabet, and march is the 3rd month, so march is the build month.
next is the letter "G" this is the year. G is the 7th letter in the alphabet,
so this would be a 1987.
here is one more..your serial resembles this:f6030578.
to start, if you have a "baseball" looking stamp behind your serial, this frame was made overseas...
no its not a pacific, so dont cry, or get mad...and lets continue.
on this serial, the first number is the last digit of the year, so 6 stands for 1986
next is "03"....this is the third month..which is march.
so you have a gt built in march of 1986.
but still use the museum as a guide to id the frame, cause sometimes you can find the year,
but getting a posotive id on the model isnt possible without knowing which style frame you have.
this doesnt apply to new gt's, but hopefully some people with info on those will chime in.
this isnt always going to match your serial, you may have a "fake"..its not likely but it happens.
also on earlier models this can differ. this is for the 2 most popular style serial's i see on here. also,
common sense tells you that if you have a suspected "gt" frame, look it up and compare it in the musuem,
knowing which style frame you have will help with the process of id'ing your bike with the serial,
especially if the serial has some damage that prevents you from getting the full number.
hopefully this bit of info can be used for everyone,
and this will save you from those late nights sitting around waiting for a response to your post looking for an answer to the idendity to your gt
...although i do feel smart and proud when i can answer these posts. well, thats it for me, if anyone else has info on serials or
if you see a mistake in this guide, tell me so i can edit it. happy holidays people.
dd. 23-01-2007
Hi,
I was just forwarded your website about the Dyno Roadster. It is great to see an appreciation for this bike after all of these years.
Let me introduce myself, my name is Jeff Soucek and I actually designed that frame while working for GT bicycles between the years 1992 and 1998.
I thought I could share a little incite to the project and how it became.
The idea of this Roadster frame actually was conceived after Sean Flickinger (one of the other GT Industrial Designers) designed the standard Dyno cruiser
frame. I was responsible for the geometry of that bike, and at the time we wanted a standard cruiser that would simply blow away the old Schwinn cruises
that were so popular at that time. We kept kicking the geometry back and slacking out the frame until it had –what we called at the time “6 pack geometry”
This meant you could be half lit and still ride it to the liquor store and them back with one hand on the bar and a six pack of beer in the other.
The next part of the story goes like this. Bill Duehring (Director of R&D at GT, and now President of Felt Bicycles) knew we had just designed a
great cruiser, and wanted to create something to stir up the excitement of this new “standard” cruiser. We really wanted to highlight the new “six pack”
geometry of the new bike. There was a small custom builder in the Huntington Beach California area where our office was, called HB CRUISERS.
This guy had made some super stretched out cruisers that we had seen the locals riding down at the beach.
This gave us the idea to take our standard cruiser design and “six pack” geometry and stretch it out to the Roadster length,
creating a “show bike” for the Interbike release that year in Aneheim California. This would be such an obviously different bike that it would help
draw attention to the “standard” cruiser line.
So I went to work hand building the first prototype of this Roadster with the help of Dan McGrew (master frame builder in the GT tooling room).
We hand formed, bent, flared and machined everything from scratch. Next we had the front half of the frame chrome plated and painted it custom
with classic chrome darts, electric blue pinstripes, and black from there back. Even the front fender and chainguard were half chromed and painted.
It was a beautiful job done by the Custom GT paintshop in Colorado responsible for all of the Custom frames made by GT at the time.
All of the other bits were triple chrome plated to car show quality, down to the 12 gage spokes and nipples.
It even had an internal generator front hub with a headlight and internal wiring.
Once the bike was complete, everybody was freaking out about how cool it was, so it was time to show it to the boss Richard Long (owner and president of GT) We approached him with the bike the day of the yearly sales meeting where all of the sales reps from the entire country were in the building. We brought it up to the meeting and called Richard into the hallway were we had the bike sitting to surprise him, and as him for permission to show it to the Sales reps. I still remember his words when he came out and saw it “Are you Fucking serious, you actually think you can sell those”. We said “let us bring it in and show the sales reps and see what they say”. He reluctantly agreed, and we left the meeting with the Reps cheering. The bike was now set to be shown at the Interbike in Aneheim. Needless to say the bike caused quite a stir at the show. When we noticed the big guys from most of competition was in our booth checking it out, Richard had us pull the bike from the show after the first day and gave us the go-ahead to make a production bike. The rest is history with this bike surprising all with the numbers sold over the few years it was in production.
Pretty interesting side note: Bill Duehring the director of GT R&D during this time is now the President of Felt Bicycles.
Some of the same guys who worked on these bikes at GT now work with Bill once again for Felt. It is cool to see that the Felt Forks/Bars, Tires,
cranks and other misc. parts you put on your custom cruiser are actually designed all by the same people. It is almost like a continuation or evolution
of the bike.
Thanks for keeping it alive and we would love to see more of your work. Let me know if you have any questions.
Best Regards. Jeff
Hi Richard,
Thanks for the pictures; those are some really nice looking cruisers you guys have!
What I really want to learn ones and for all is the story of the "six pack geometry" frame!
The story is basically the same as what my first e-mail stated. All I can really add is the "6 pack" idea came from where I lived
at the time. My appartment was in Huntington Beach California, about 1 mile from the beach, across the street from the liquor store,
and what we called the "surfer ghetto" This is where all of the surfers who didnt work all day
so they could surf lived, but didnt have enough money to live on the beach. Every night I would see them roll up to the liguer store in surfer shorts
and flip flops on their cruisers. Half of them were allready drunk and it was funny watching them try to ride back to the beach drunk, one hand
holding a 6 pack and the other one trying to steer the bike down the road. What year was the first one made?
I really cant say for sure what the year was for the first production bike, but I think around 95 or 96. when did it get the name Roadster,
when the bike was put into production.
Why is it now called Kustom Kruiser? I have no idea, maybe when GT started doing the "theme style cruisers" the name changed...
What colors did the Coaster and Roadster come with? I think the original colors were black with white pinstripes, and red with white pin stripes.
They changed every year.
What does the serialnumber tell us? Im not sure what the serial number tells, but the frame was manufatured in Taiwan by a really nice frame shop call
Inchaun. The guy who ran the shop was called Jim and he was a fantastic builder. I believe the frames were assembled in Taiwan by a factory called
Sanfa Bike.
Most of this is just from memory and it has been a lot of years and many
bikes later. I hope this helps...
I did speak with Mr. Rhalf van Heusden last night. And confirmed to him
that the cruiser he sent me pictures of is indeed the original hand built
roadster.
Thanks for the link to the forum page
Best Regards
Jeff Soucek
On the colors, ya I think Candy red was the original red along with black.
The solid red came a few years later because it was more "Hot-Rod" instead
of "lo-rider" I remember there being a candy blue as well, but not sure if
it was the first or second year.
No problem on posting my comments, it's always nice to see some old projects
that just won't die smile.gif
Jeff Soucek / Felt Bicycles
Senior Design Engineer