Question about 2018 G310R Exhaust Gas Sensor

What an interesting challenge you’re undertaking. I hope it works out. S/ JerryG

Unfortunately, your O2 sensor wiring has four wires whereas mine has five wires.

However, I found a picture of the connector for a G310GS 4-wire O2 sensor online; it’s the second picture below.

1) Is this sensor the original part for this bike?
A: Yes. It’s the same as my first pic below. You can check this further by cleaning the barrel of your sensor and looking for the following:
On sensor, on the barrel above the nut, I have the following: “8393888-03”, “NTK JAPAN”, and “ZU3”
On sensor, on barrel below the crimp at wire end of the sensor, I have the following: “12EC”
On the other hand, yours might have different writing if the O2 sensor is older than mine; which is likely since I have fire wires to your four.

2) If so which color wire from sensor should connect to which numbered hole in the bike’s plug and how?
A1: Order of colors: See the second picture I’ve attached. To me, it looks like Black, Grey, White, and White, but make sure you have the correct side of the connector facing you so you don’t reverse the order.
A2: How: Push each of the four pins you show in one of your pictures into your O2 sensor side connector. The green triple flange on each wire forms a water tight seal and centers the pin in the hole. When inserted correctly, you should be able to look into the end of the connector and see the four pins. When you connect the O2 sensor side connector to the bike side connector, the pins should fully connect to the wiring harness.

3) Engine starts and runs. Will the engine be damaged by running with the sensor disconnected or just some performance issues?
A: I’m not a mechanic, but my understanding is that (1) it won’t damage the engine; and (2) the engine won’t run as well because the Engine Control Module won’t have the readings from the disconnected O2 sensor to help it adjust the fuel-air mixture going into the engine. You should double check this with a mechanic. If no one on this forum chimes in to confirm or deny this, we should move this discussion to the Tech Session at the g310rforum.com (link below). There are people there who are mechanics or at least much more so than I am.

4) I have recovered the core of the original exhaust system and installed it. All shielding and trim has been stripped off by thief.
A: There doesn’t seem to be a question here. Semi-related: I removed my OEM exhaust two year’s ago when my bike had just 4 miles on it. I have watched so many of these languish while listed for sale that I’ve concluded there is no market for selling them. So, I have mine listed for Free $0 (you pay shipping) at the link below.