Yeah, it'll be for a Lambda sensor, you can get far simplier ones that just read exhaust gas temp onto an LCD disply on the dash. Different mixtures result in different temperatures.
What you do is determine what the idea mixture/temperature is by running a few plug chops and rejets until the bike runs perfectly, you then know that temp = ideal.
Then at the race you can see instantly if your motor is running optimally.

Why is there only one? Maybe he only had one sensor
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