Any successful DIY neutral switch installs on MK2?

art6

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I am aware of the "don't try it" conclusions from attempts to install a neutral switch/indicator light on pre-MK3 Commandos. But if someone on this forum has successfully done this, I would really appreciate your advice. It doesn't have to be "original-looking". Thanks very much.
 
Well I'd think you would start by drilling and thread tapping where the MK 111 model switch exists .
With a NO plunger/roller switch threaded into the hole, is it just a matter of machining a notch in the cam plate that will engage the plunger when in the neutral position?
 
And just cos the light's not on, doesn't mean you're not in (a) neutral!
I'm not worried if it isn't perfectly reliable; that's just the free education that comes with ownership of any British bike. I was hoping to find an online tutorial showing a sorta successful DIY?
 
As far as I know its never been done, if the MK3 has a casting modification to give the switch thread more support then a pre mk3 will be missing this and need some way of giving the extra support likely by adding weld and then dressing flat. You do already have an indicator pointer on the gearchange lever shaft but you can't see it from the saddle, maybe replace with a sensor.
 
I have to admit, that I toyed with the idea of fitting a neutral light. I was going to use the bolt on the end of the detent wheel spindle to either attach a cam to activate a switch, or a magnet and Hall sensor or reed relay.
 
Or you can buy a MK 111 cam plate ?
Is a MK2 cam plate the same as a MK3 plate except for the hole for fastening a neutral position bump? If so, it's just a matter of drilling a hole like the one in the Andover replacement cam plate, below?

Any successful DIY neutral switch installs on MK2?
 
I have to admit, that I toyed with the idea of fitting a neutral light. I was going to use the bolt on the end of the detent wheel spindle to either attach a cam to activate a switch, or a magnet and Hall sensor or reed relay.
A Hall effect sensor seems like a great idea. You must be an EE. The technology probably postdated the early 70's. A small magnet attached securely to the cam plate would do it. Maybe a short cylindrical magnet press fitted into the hole. There are countless automotive Hall effect sensors that could be screwed into the hole in the case facing the cam. No actual contact with the bump, so no worry about repeated force loosening it. Might have to drill one or more teensy test holes in the case to be sure the final hole is exactly above the bump in neutral(?) Fill in with Devcon F.

There's probably something I'm missing. Its been 50 years since I had a MK1 gearbox apart, so I'll surely be back here. Thanks all.
 
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Is a MK2 cam plate the same as a MK3 plate except for the hole for fastening a neutral position bump? If so, it's just a matter of drilling a hole like the one in the Andover replacement cam plate, below?

View attachment 125484
Yes . Andover supply a harder material neutral indicator pin now that hammers / peens into place , to replace the old type pin . This mates with the newer type switch . I have done this , works well , reduces wear .
 
I have fitted a proximity sensor that has the capability to directly illuminate an LED to my MK3, I also know someone who has fitted a neutral switch to his pre-MK3. Some pre-MK3 camplates may already have the hole for the button on the camplate, likewise some gearbox shells may have the casting with extra material internally where the switch fits. If anyone wants details of the parts I have fitted then contact me, the parts are also readily available in the US. Some may see the magnetic sensors which are way cheaper than the proximity sensors, but I decided against fitting one of those.
 
The current setup I have is relatively simple, using an Omron E2E M5 Proximity sensor and a VCC LTH5MM15VFR4500 led. This allows the small current output from the sensor to illuminate the led. The Triumph triples use a similar setup where they used the same mechanical switch as the MK3, though the kit is available from Greece, it uses a relay to illuminate the neutral lamp.
The temporary adaptor I made is a modern cut down Lucas switch which is drilled and then tapped M5 fine (0.5mm pitch) and sealed in the original thread in the gearbox with adhesive sealant. The sensor is then set to the button on the camplate by screwing in gently until it stops and then turn it our one turn. The sensor range is 0.8 – 1.2mm so the thread pitch can be used to set the distance, a bit tricky when the gearbox is in place but a doodle when I did it on my desk. For the MK3 there is no need to modify the camplate unless the existing button is very worn, mine is and it still works and this was part of my test plan to use it against a worn camplate button.
 
Yes. But after riding a Norton for a few rides knowing if you are in neutral or not will be second nature.
On my 850 and original gearbox, if the chains are adjusted right, clutch is right I fine putting my GB into neutral it has a lighter click than the gears so I can feel when it's in neutral, it just comes natural for me to feel it, if your Norton is hard to get into neutral then something is not right, primary chain, rear chain and clutch adjustment more likely or rider error, if adjusted right a soft click is neutral for me as well I can feel it as well, also easy to look down and see if the indicator on the gear shaft is on the N if you still have it, I lost mine about 30 years ago but as I said I can feel it when it's in neutral.
But then I only been riding my Norton for 50 years, what would I know lol, it's the same as kickstarting a Norton you have to have the Norton knack.
 
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