Mongoose Kos Kruiser Serial Number Decoder: Find Out the Year and Model of Your Bike

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

mongoose kos kruiser serial number

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In early 1976, the letter C was added to denote CROMO. During the early production of the Mongoose frames they were made using 1010 steel tubing. problems with the heat from welding and breakage at the weld points, forced a change to Chrome Moly tubing. Both frames looked the same but needed some way to determine the difference due to the frames being nickel plated or powder coated paint as it was impossible to tell the difference in the material for warranty reasons. The letter C was used for chrome moly, so the serial numbers would look like C17834.

In May 1976 the serial number process changed again with the addition of a month code. From here frames were stamped with the letter C for Cromo, a letter for the month, and a number for the year of production. It was around Feb/March 77 that the extra single gusset was dropped from the frame. Of course these are general guidelines in identifying Mongoose frames and there are the anomalies to this process of serial number identification. The serial numbers were hand stamped on the bottom bracket tubes, then packed in (empty beer) boxes waiting to be welded to frame tubes.

Serial numbers that ran from May 1976 through to March 1981 will have three digits in sequence overtop the serial number of that frame. This guideline also applies to Team Mongoose, Supergoose, Jag, Blue Max, Roger DeCoster, Super-X, and Moto-Trac frames. 2ff7e9595c