| Diagram | Fig. 31 — SPEEDOMETER AND TACHOMETER · ref 7 |
| Subsystem | electrical |
| Listed in parts books | 1964–1969 |
NUT, 5MM X.8 SPEEDO MOUNT
A 5mm x .8 nut used to mount the speedometer (or tachometer) on Triumph instrument setups.
This is the small nut Triumph used to secure the speedometer (and on some setups the tachometer) mount, in a 5mm x .8 thread. It shows up in the parts books under the speedometer and tachometer figures, sometimes grouped with the tail lamp fittings on later bikes, which tells you it's part of the hardware holding the instrument or its bracket in place rather than anything inside the gauge itself.
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It's a plain, low-cost piece of hardware, but it's the kind of small nut that's easy to lose or strip when a speedo or tach gets pulled for service, so it's worth having a spare on hand. Catalog records for this one run from 1964 to 1969 across a number of listings, which speaks to how many bikes and gauge setups it turned up on over that stretch, though our records don't spell out which specific models beyond that.
It also carries an alternate number, 90591A146, so if your parts book or an old invoice shows that number instead, it's the same physical nut.
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