Bridgestone Motorcycle Parts Discussion Board

Bridgestone Tech Talk => 50, 60, 90 & 100 Talk => Topic started by: Old BS Guy on October 09, 2016, 03:09:46 AM

Title: Serial / VIN # compatibility;
Post by: Old BS Guy on October 09, 2016, 03:09:46 AM
Hello to all, and nice to be back on the forum again. I've run into an oddity and need some help. All my other BS bikes have had engine numbers that matched the vin model. I purchased a couple of 100's today for parts, and received quite a surprise. The 100 Trail-OI, has a serial number of 22C000055. Acording to Grahams fine work with the numbers list, this far precedes the earliest known production, even by month. My concern is this: the engine number is 20C 005773, which would be a 100 Sport engine designation. Of course, my first thought was, someone changed the motor. When I look at the production date for the 20C, it becomes apparent that the date coincides with the production date for the 100T. Since they only made the 100 Sport for 67 & 68, I wonder if they pulled engines already stamped for that line to use in the just emerging 100T production. This bike being one of the first 100 made, and with a matching frame nnumber of 000058, makes me believe the engine is original. The other bike I received is a '71 100 TMX, with a VIN of 22N013134, making it a Feb. '71 production, and it also has a 20N motor in it, but it would be Feb. '67. The sticker on the steering head indicates a build date of Feb. '71. Maybe both motors have been replaced, and it's just coincidental. I'm excited to have come up with the low VIN on the 100T, however, and believe it may now get restored, not parted. If anyone can shed light on the 20 series engines in 22 series chassis, please respond. Thanks!

UPDATE:...... Upon reading into it further, I see that our late friend, Graham, addressed this as, in fact, a common practice, and the 100's were produces with 20 series engines. Topic closed, but comments encouraged.