speedo light dimming

[cadetchris]

recently noticed that the intensity of my speedo dial keeps varying, sometimes its lovely and bright and other times its quite dim.
initally i thought that it was to do with the charging of the battery, but the headlights dont dim or brighten when accelerating and the battery is in relativly good charge most of the time, the regulator is new and the dynamo is also nice and new.
so all in all, i am quite confused about it

[aupickup]

maybe just a bad connection

[nigelr2000]

Check the switch under the speedo as its a really awfull design, just operate it a few times with the lights off and that might clean the ciontacts up enough to make it work properly without goint to the trouble of removing it for repair.

[mike.perry]

Is it both backlights that go dim or just one?

[cadetchris]

strangely, one of the light bulbs always burns out instantaneously and the other one varies in brightness.

[mike.perry]

You are fitting 12V bulbs?

[cadetchris]

yep, 12volt bulbs are fitted

[mike.perry]

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