Frame ID > Serial #

Interpreting the Serial numbers and features

on BMX Products, Inc. Frames

Identifying the serial numbers on the early Mongoose frames is actually quite easy and intuitive. For the most part the early Mongoose frames from 1975 and into early 1976 were done with hand stamped 5 digit numbers starting from 10000. For example, a frame from 1975 will have the numbers like 11994.

A feature of an early 1975 frame is the brake tab. The brake tab on these frames is rectangular in shape as opposed to later years when it became a single layer of steel as well as more oval and thinner shape.

The 75 coaster brake tab is also thicker and is comprised of two layers of steel welded together

Another feature of an early 1975 frame was the chainstay brace where it connected the seat tube. Note the flared shape of the 75 frame vs the later style (which carried on through all the later years of this frame style) and the extended seat tube.

A further feature was the headtube was offset to extend more to the bottom than it was to the top. It is our guess that it was done this way to allow clearance for the squarer shoulder on Ashtabula forks. This feature carried over for the first few years till the ashtabula forks were replaced with the more rounder style Tange made forks.

Sometime in 1976 the letter C was added to denote the office location of Chatsworth, California so the serial numbers would look like C17834.

Another feature of an early frame built in 1975 and 1976 was the extra single gusset above the bottom bracket.

In mid 1976 the serial number process changed again with the addition of a month code. From here frames were stamped with the letter C for Chatsworth, a letter for the month, and a number for the year of production. It was also in this year that the extra single gusset was dropped from the frame, although, there have been frames in 1977 that had the extra single gusset.

Of course these are general guidelines in identifying Mongoose frames and there are the anomalies to this process of serial number identification.  

In an interview with Rick Twomey, the serial numbers were hand stamped on the bottom bracket tubes then packed in (empty beer) boxes waiting to be welded to frame tubes. The welders were supposed to grab the box at the bottom of the pile but many times the welders just grabbed the box that was easiest to get to, this would explain why there are frames out there with earlier serial numbers used in later years of production.

As Rick Twomey explained the process, the frame components were manufactured in different stages and or departments and some of the parts were exhausted quicker than others, it this process that lead to some of the frames “crossing over” to different years, especially during the end of the year. 

RECO (Racer Engineering Company) manufactured frames for BMX Products, Inc. for the first 3 years of production, after that the frames were made “in house” by BMX Products, Inc. According to Rick Twomey, RECO was a frame welding company that BMX Products, Inc. used to make their early frames. As Rick remembers BMX Products Inc. in the early years moved into the unit next door to RECO and eventually bought them out.

So as a general rule the serial numbers that ran from 1977 through to early 1981 will have three digits in sequence overtop the serial number of that frame. Let’s look at some serial number examples below to get a better understand how the process worked.

This guideline also applies to Team Mongoose, Supergoose, Jag, Blue Max, Roger DeCoster, Super-X, and  Moto-Trac frames. 

Each frame had a combination of three key numbers or letters.  For example: 

CH8 123456

Again, the C stands for Chatsworth [California] where the frames were manufactured. The next letter in the sequence is the month code.

A = January
B = February
C = March

The next number is the last number of the year the frame was produced.

6 = 1976
7 = 1977
8 = 1978
9 = 1979
0 = 1980
1 = 1981

The rest of the serial numbers are sequential and are the number of frames produced in that series.

NB: Super X has an “X” instead of a “C” in the serial number.

The Team Mongoose and Supergoose frames are a little different. The same coding applies to the first part of the serial numbers as we discussed above, however, if a capital T is in front of or above the CXX  it indicates that it is a 100% Chromoly frame.  The Team Mongoose, Team Minigoose and Supergoose, all should have a T in this area. (Moosegoose, Two/Four, Two/Six, and the Kos Krusier  also have 100 % Chromoly tubing).

Serial numbers after 1981

Starting in 1981 and through 1982 or so the frames were coded differently. They started out with a letter followed by a sequence of numbers.  As before, the letter indicates the month and the first number or the second digit in the sequence indicates the last number for that year.

J2009981: according to this serial number the frame was manufactured in October of 1982.

Sometime in 1982 the bottom bracket brace was replaced with an open design (see picture below). USA made frames from post gusset era, still had the month first, then the year but they were stamped not on the bottom bracket but on the brace behind the bottom bracket. All USA made frames after they dropped the “C” were month, then year, then serial number.

As a general rule anything with a Gusset behind the head tube was manufactured in the USA.

There are a few key components to look for on a BMX Products, Inc. frame.

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