1983 XJ900 31A Oil Level (pressure) Warning Light issue

I am in the process of replacing the original XJ900 instrument cluster with a Daytona Velona W digital gauge, (part of cafe racer conversion and the original speedo stopped working anyhow). Have everything working properly on the new gauge and now looking to remove the left over bulbs from the old cluster. When I remove the original Oil Level Warning Light bulb, the same indicator on the new gauge changes behaviour and only comes on with the Stop Switch on the right handlebar cluster (and not briefly when the Ign is turned on when it gets a signal from the Oil Level Switch). Note that the new gauge only has a single wire for Oil Level Warning and is wired to the negative side. Obviously I don't want to keep the original bulb, so the question is how do I remove it whilst making the new indicator come on briefly during Ignition, and on when the Stop Switch is turned on? I tried inserting a 2.2Ohm resistor between the wires going to the Oil Level Warning Light bulb, removing the bulb and testing, but this didn't work.

 

I know that the XJ900 oil sensor is the reverse of the XJ750.

I swapped a XJ900 oil sensor with a chap who bought a dash that needed the opposite on his 750.

Hmmm... Not too helpful probably but I know I had issues with my stock dash 750 with the 900 engine and sensor until we swapped and I put the 750 sensor in the 900.

Destiny maybe.

Lol reading my reply may be as confusing as your question.

 

If this is the gauge you used:

https://www.wwag.com/step/pdf/247312.pdf

Then the purple wire (warning) would replace the B/R wire in the below diagram.

I believe the resistor is 8.2 ohms in the Yamaha diode block. The data sheet on the gauge doesn't spec current, but odds are it's an LED so I would say the resistor is not needed

The diode, not labeled is needed to prevent a low level oil warning from engaging the starter and is used only if you want the oil level light to illuminate with the starter button.

The oil level light illuminated during starter engagement is not really necessary but I suppose it supplied some reassurance that the bulb is OK. It can also be an indicator of whether ignition power is good, which can be a nice feature.

The original setup is oil warning switch normally open and warning illuminated (switch closes) when low oil. You should just stick with that logic

If I was doing it I would just wire the purple to the oil sensor and be done with it. And, then remember during oil changes to set the ignition switch to ON and verify the oil sensor is working by observing the warning is illuminated.

 

I also bought the Daytona Velona. The oil lamp is now constantly on. I have an XJ750 Seca and understand my oil level sensor is “normally closed” type, can I replace this with a “normally open” type sensor? Will the XJ900 sensor fit on XJ750 Seca?

 

So pretty sure it is a bolt in replacement, and if you look at the part number you have a lot of choices when selecting the normally closed version that opens when oil level is sufficient as it was used in many places

https://www.partzilla.com/product/y...?ref=e1e528af7c5af5ebc7fb4519bff3782aff75dc54