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Discussion Starter · #1 ·
I'm in process of restoring/modifying 1980 CM400t. I'm a newbie to engine mechanics and I'm using project as a learning experience so taking it slow, trying to absorb as much as possible from shop manual, online forms, books, knowledgeable friends, etc.

I'm stump by one component which i can't identify. I think it might be the neutral switch, it sits on top right side of crankcase behind cylinders (item circled in red on schematic). If it is neutral switch and I plan to replace original instrument cluster with just tach and speedo, do I need neutral switch?

Same question goes for oil pressure switch, do I need to wire if I'm eliminating oil pressure warning light?

Screen Shot 2018-03-08 at 3.20.32 PM.jpg
 

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You are correct about the neutral switch. Beyond lighting the dummy light it also allows you to start the bike in neutral while preventing you from starting it while in gear. I would recommend leaving the wiring for this intact even if you won't be using the light, but you can cut it out without affecting anything else. As for the oil pressure sensor you can remove all associated wiring no problem.

Do you have the factory service manual?
 

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Discussion Starter · #3 ·
You are correct about the neutral switch. Beyond lighting the dummy light it also allows you to start the bike in neutral while preventing you from starting it while in gear. I would recommend leaving the wiring for this intact even if you won't be using the light, but you can cut it out without affecting anything else. As for the oil pressure sensor you can remove all associated wiring no problem.

Do you have the factory service manual?
Thanks much for response. and yes, I do have original shop manual, a 300 page pdf .
 

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I'm not sure why you'd want to eliminate either light. The oil pressure light let's you know if the oil pressure drops to a point of engine damagee or pre-failure. It triggers at 3-4.5 PSI. The neutral light confirms you are in neutral at a stop light so you don't release the clutch thinking you've hit neutral while still being in a gear. Really embarrassing to pop the clutch and run into the car or bike in front of you.
 

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LDR has a solid point here. Not having these lights can be a pain. I've been without them for 2 years now and finding neutral can be a serious pain sometimes. I've had no problems without an oil light but I keep on top of oil level real well. An elegant solution might be to replace your dummy lights with LEDs mounted in the headlight bucket. Also without the indicator, it's REAL easy to accidentally leave your turn signals on by mistake. If you check eBay you can find LEDs with a resistor already installed to make them compatible with 12V. If you do this you should be able to consolidate the two turn signal lights into a single one if you isolate the circuits with diodes. Doing this you could end up with only 4 LEDs mounted in the bucket, for neutral/high beam/oil/turn.
 
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