Digital Gear Indicator for the XS650

Here's the problem with the momentary on-off-on toggle switch.
SwitchRegions.jpg


The actuation regions of the switches I've been using are inconsistent from switch to switch. And, those regions may change over time.

What this thing needs is a switch mechanism with these criteria:

- Snap action contact, with hysteresis (the trip/reset zone).
- Contacts only after 9-10 degrees of shift shaft rotation, from center.
- Tolerant of vibration, heat, oil, water, dirt, language.
- Which probably means sealed.
- Fine-tune adjustability at the endpoints.

The most important part is to have NO chance of switch activation until the final 1-2 degrees of rotation. The little clamp lever swings a 3/4" (19mm) radius. 1 degree of rotation gives 0.013" (0.33mm) of travel. For adjustability, that's a small fraction of a turn for a setscrew.
 
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.....right - gotcha.

So, wouldn't a roller limit switch (actually, two of them would be needed I guess) work well - if set to actuate right in the "certain shift" zone in the up-shift and down-shift directions?

?????
 
Excellent work at characterising the key issue! Would there be any mileage in changing the switching position/direction? I realise space is tight so perhaps you could run a flat piece of metal from your switch-mount horizontally backwards in the direction of the rear tyre. On the end of this place two magnetic reed switches. Then from the bat-faced clamp have a metal rod run back horizontally and fit a small magnet on the end. Depending on the length of the metal rod you will get a greater separation distance between each degree and possibly improved precision for the switching???
 
...So, wouldn't a roller limit switch (actually, two of them would be needed I guess) work well - if set to actuate right in the "certain shift" zone in the up-shift and down-shift directions?

Yes, microswitches have been used for a long time for precision positioning and limit switches. Those "D2F" ultra mini switches are quite small, about 1/4" square by 1/2" long.
Switches-UltraMini.jpg

I'd need to cut off and reposition the welded mount tab to get them in there. Then, design a mount plate, with a centering swing lever and two adjustable sub-plates.
 
Excellent work at characterising the key issue! Would there be any mileage in changing the switching position/direction? I realise space is tight so perhaps you could run a flat piece of metal from your switch-mount horizontally backwards in the direction of the rear tyre. On the end of this place two magnetic reed switches. Then from the bat-faced clamp have a metal rod run back horizontally and fit a small magnet on the end. Depending on the length of the metal rod you will get a greater separation distance between each degree and possibly improved precision for the switching???

Thanx, Paul. Yes, using the supplied magnetic reed switches and magnet would certainly reduce the parts 'outsourcing'. It would be similar to this implementation:
ShifterSensor03.jpg


There *is* a bit of room in there. The instructions state that the minimum reed spacing be 1". With only a +/- 11° rotation, that would require an arm length of at least 2.6".

This could also be where Resto's mounting idea could work, with the reed switch mount plate affixed to the sidecover. Just needs some method of adjustment after installation.

With your mounting of the reed switches, to the shaftguard mount and behind the magnetic lever, the wiring system can be kept, and adjustments would be done before reinstalling the sidecover...
 
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I'm also studying other switch types.
I have parts to fab a leaf switch like these:
Switches-Leaf.jpg

Notice the self-centering 'moving leaf', sandwiched between the two contacts. I could put it into a sealed tube, with a protruding finger.

I also have an abundance of "tactile switches" to play with.
Very tiny, less than 1/4" square.
Switches-Tactile.jpg

Then I found this, "bidirectional detector" switch, as used in rotary encoders:
SwitchesDetector.jpg
 
I have this recording in my head.
It's RetiredGentleman saying: "You're overthinking this.".
Helps to knock me outta the spiraling vortex.

So, back to wiring and testing.
The headlight bucket, everybody's favorite playground.
GearIndicatorTest05.jpg

Checks out fine. Unfortunately, my camera doesn't do LED displays very well. It actually shows a "0" up there, not an "8"...
 
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Thanks! My Britbike buddies mentioned that they were running a bit short on that stuff.
 
I had hoped to be able to do this thing with easily available parts and such.
It's not happening.

I wanted a small, simple, sealed mount for the 7-segment display, and put it between the instruments. Less than a 1" gap in there, but enuff room for a small display, especially if it's rectangular. My searches for such an enclosure came up dry. So, have to fab-up some sort of mounting.

Beat some metal into submission, the paint's finally dry.
LED-DisplayMount01.jpg


Tentatively assembled.
It will look similar to the Dakota Digital tubular display.
LED-DisplayMount02.jpg


The mount will clamp to the little channel-shaped crossover of the instrument mounting plate, at this circled location of part #9.
70-72-Speedo-Tach-Crossbar.jpg
 
Hi 2M,
How about fitting a disc to the shift shaft with holes drilled in the disc (say 20 degrees apart) that are detected by a slotted optical sensor? This would not trigger until full shaft rotation. Disc could be welded/glued to a collar with a grub screw securing the collar to the shaft, allowing some adjustment.
No mechanical parts and should be able to fit in the tight space. Only issue could be chain gunk blocking the optics. See slotted sensor below.

images.png
 
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...How about fitting a disc to the shift shaft with holes drilled in the disc (say 20 degrees apart) that are detected by a slotted optical sensor? This would not trigger until full shaft rotation. Disc could be welded/glued to a collar with a grub screw securing the collar to the shaft, allowing some adjustment.
No mechanical parts and should be able to fit in the tight space...

Hey, Phil. Yes, another good one. Parts for that could come from old computer mice.

...Only issue could be chain gunk blocking the optics...

And, that's the catch. All that grit/gunk/goo down there. Pretty hostile place.

I've been studying some leaf type switch parts. They're 1/4" wide, and could fit into a 3/8" - 1/2" sealed tube. Is this thing getting complicated, or what?
Switches-LeafParts.jpg
 
2M - that has to be the coolest XS650 cockpit this side of the Space Shuttle.
 
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