Inside The Tachometer

[3Phase]

This is to show how the tachometers are made.

Yamaha XS1100 Tachometer













I don't have any pictures of the bottom end of the tachometer 'motor' with the Red wire.

The bottom is almost identical to the top with a coiled hairspring but it has a very fine bearing where the armature rests. The lower bearing doubles as an electrical contact for the Red wire just like the top bearing does for the Black wire but the spring and armature bearing preloads are both adjusted and set at the top and the bottom is not adjustable.

When the lower bearing gets worn, dirty and/or sticks after rotating, bouncing and vibrating or just sitting for who knows how many years then the armature will move slowly, stick or even briefly lose electrical contact and bounce. The needle will do all sorts of strange things but mostly it'll bounce, stick or drag.

Anything that's leaked, sprayed, blown, flowed, glopped or dunked into the housing finds its way to the lower bearing.

It's just the mechanical side of the tachometer but that's what little tachs are made of.

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[skids]

Good god man! That is a bunch of unfamiliar parts. I'm just a country doctor, Jim!!!

[3Phase]

One of the bad tachometers turned up in the junk pile so I took it apart to use my new camera and the new JIS screwdrivers.

These pictures are the tachometer Positive lower end of the 'motor'. It's actually a galvanometer but no one cares so get on with it!





The hairspring broke off and was sitting in the bottom of the tachometer housing when I opened the housing.









That's all, folks! (Exit, stage left!)

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[soccer4m]

Beautiful Pics 3Phase

I think you have a new career waiting for you Scott,,,nice pics,,great detail, background etc. The new camera pics are like having the items in front of us. Its amazing that this site went from all text years back to this level of detail,,,so much easier to keep these bikes on the road. So, hope all is good in your life, maybe give Roo a call to motivate him to get the Greenie Kawi back on the road. It was fate that he broke down in Beaver Utah,,,next time we avoid that city........see ya, Mike in Sun Diego

[3Phase]

Thanks, Mike! I missed you guys at the rally.

I'm still learning how to use the camera but it does make nice pictures even on the automatic setting. As I told 'Roo, I was gobsmacked when I heard where y'all had broken down! I'll have to go up and see how Greenie's doing after total oil pressure failure.

Before the interweb-thingy I used to use only text with no images except for the occasional rudimentary illustration or ASCII art. At the time I was using technical newsgroups and other, private, systems where you had to be very precise and concise, not only to conserve bandwidth but to ensure you did not choke the text-to-speech screen readers for the blind subscribers. I also used only 7-bit ASCII and avoided contractions, slang and colloquialisms to minimize technical problems during routing and for the non-native English readers and the rudimentary translation software programs.

The writing style and habits carried over to the web and it made me 'sound' like a robot or an egocentric jerk with an extremely high opinion of himself. Of course it's all true but everyone likes pictures with less text now so it works out.

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