Tuesday, December 5, 2023

1971 Triumph frame construction


Frames are set up in a jig and welded.


Because this new frame was also the oil reservoir, each frame was pressure tested by dunking into a tank.


Steering head bearing receptacles and swingarm pivot are machined.

March 1971 Cycle Guide

 A

5 comments:

?? said...

Make sure they don't forget to clean out the main tube/oil reservoir...

JP said...

Good advice. You might trust the Japanese to properly clean it somewhere
along the manufacturing process. The British... not so sure.
Just thinking of a friend's recent (mis)adventure with a brand-new Cheney
OIF frame. The strainer caught the big chunks, but still...

rats said...

Even with a bike lift, accessing the strainer at the main downtube's terminus was no picnic. Just one of the several features that made me allergic to post-'70 Triumphs (I disliked the allegedly improved handling, too; and the seat height; and and and ... one was plenty.

In the 1970s, a lot (or so it seemed) of misguided people tried to make choppers based on OIF Triumphs. This worked out most excellently for me. Welding a hardtail to one of those frames, a terrible idea in the first place, often resulted in a ruined frame as the stick or torch blew a big hole in that very thin large-diameter tube. Guys would do that, lose heart, and park their newish bikes in the weeds. I bought three, count 'em three, 650 Bonnie engines from such guys for $50-$100 apiece. None of the engines had more than 3K miles on it.

rats said...

Forgot to say how much I loathed the '71 front brake. And the forks (though, yes, a small improvement on their predecessors). And the looks and the weight and the controls.

The seat was okay, I guess.

Anonymous said...

Was this pre-strike then? It was legend that when the big labor strike happened that the workers pulled all the decades old shims out of all the machines used to build frames and other parts and not one was made right ever again....