T120MYGE25649
If that number doesn't make sense, I thought the Y might be a V, and I'm not sure if it's GE or GS. I originally thought it started 1120, but I guess it must be T120,
You and "New2triumph" are definitely against the wall come the Revolution ...
Rather than struggling to figure out the frame number, look down at the left-hand crankcase, just under the cylinder block; if you want us to hate you even more, you'll see the same "T120" and "GE25649" stamped there, along with "RV" (not "MY" or just "V") between them, and probably more readable. Otoh, if you can only access the frame number, put some talcum powder on a finger and rub it over the frame number, the white powder will settle in the indentation of the letters and numbers, showing them up better against the black frame paint.
If you have "T120RV GE25649" on both frame and engine, and the special gearbox is still in it, you have one of only 200 built. But it's a few "ifs" ...
Back story. The AMA changed Class C racing rules for the 1970 season, allowing engines to compete on capacity only, removing the previous 500 cc OHV vs. 750 cc SV restriction. BSA/Triumph decided to compete with the-then one-year-old triples.
Come 1971, the AMA required at least 200 of any engine or part of to have been made available for sale to the public; theoretically, this (along with the 'claiming' rule) was supposed to stop makers filling engines with unobtainium and costalotium bits that the average racer could never get, never mind afford.
In 1970, BSA and Triumph had fitted their triple racers with 5-speed gearboxes, something none of the bikes available to the public had. In 1971, BSA and Triumph's US importer decided to bankroll an all-out attempt to win the No.1 plate. Small Heath and Meriden duly produced 200(-ish) Rocket 3's and 200 Tridents with 5-speed 'boxes developed and made by independent engineer Rod Quaife. Initially, triple racers were built for both road- and off-road (mile and half-mile) racing, but the off-road bikes turned out to be too heavy, have the wrong power characteristics and insufficient ground clearance. So the team riders switched back to 650 twins for off-road events, which immediately put them at 100 cc and one-gear disadvantages particularly against H-D but also several of the other competing makers.
So Meriden rushed to homologate 200 Bonnevilles with 5-speed 'boxes - the standard 4-speed model was coded T120R, the "V" was added to signify the 5-speed 'box (the Quaife 5-speed 'box wouldn't fit in the BSA Lightning so Small Heath produced 202 A70L's - essentially 650's stroked to 750). Afaict, all the '71 T120RV's were built in June ("G") 1971 ("E").
However, before you get too excited, as I say, you need to confirm both frame and engine have the same codes and numbers, you also might want to check with either the VMCC or TOMCC in GB that Meriden stamped the numbers on a T120RV. More difficult, you need to find someone who knows specifically how a Quaife 5-speed differs from a later production one, to ensure the engine still has the correct gearbox internals.
And Gary Nixon won the No.1 plate for Triumph in 1971.
I am not familiar with the numbers as much as some here who I am sure will be along soon,however the T120 will be a start,that is a model number surely.
