[TR] Crazy Tach

[Rick]

I had exactly the same experience a few years ago during my TR3A rebuild
with a new cable. These cables have a square key formed into each end of the
round cable which is designed to fit into the tach and drive, respectively.
This key is formed by a compression tool (many shops use a manual tool that
is wacked with a hammer) to create a square cross-section of 0.125" on a
side. The problem with my cable (in fact I went through 2 of them) was NOT
the key length but rather the cross-section, which was several thou
oversized and would not fit fully into the tach receptacle. I ground off a
bit on each side so that the key fit smoothly into the tach, which solved
the problem. Since then I found a local Brit motorcycle shop that had the
compression tool, and I run all of my new cables through him (they're all
oversized as purchased) for size adjustment. 

 

Rick in Seattle

 

1960 TR3A

1970 BSA 441 Victor Special

1972 Norton 750 Commando Combat

1975 Norton 850 Commando Mk3