Royal Enfield Lambda (O2) Sensor for Interceptor 650 / Continental GT 650 (Exhaust Oxygen Sensor) – 1020009/B

The Royal Enfield 1020009/B Lambda Sensor (also called O2 sensor / oxygen sensor) is mounted on the exhaust system and monitors oxygen content in the exhaust gas so the ECU can correct the air–fuel mixture. A weak or failed lambda sensor can trigger a check engine light (MIL), cause poor fuel economy, hesitant throttle response, or inconsistent idling—especially after exhaust work or when the sensor wiring/connector is damaged.

This is a genuine Royal Enfield part number 1020009/B, used on the 650 Twin platform in the exhaust group. Verified dealer microfiche/fitment pages list it for Interceptor 650 and Continental GT 650 (Euro 4 / Euro 5 market variants).

Also searched as: RE oxygen sensor, lambda sensor 650 twin, O2 sensor Interceptor 650, GT 650 exhaust sensor.

Before you buy: confirm the part number 1020009/B, and match your sensor connector + harness length with your existing unit (photo match recommended).

Key Features

• Genuine Royal Enfield Lambda (O2) Sensor – Part No. 1020009/B

• Fits the exhaust oxygen sensing function (fueling correction / closed-loop control)

• Direct replacement for a faulty sensor causing MIL light / fueling issues

• Helps restore stable idle, smoother throttle response, and correct AFR correction

• Listed under Exhaust / Silencer & Exhaust Pipe parts group by multiple sellers

• Best practice: replace when the sensor is damaged, contaminated, or wiring/connector is compromised

• Return-prevention: order by part number + connector/photo match, not by “generic O2 sensor”

• Suitable for OEM exhaust or stock-style exhaust setups (verify bung position if modified)

Compatibility Table (Critical)

Explicit exclusions (return-prevention): Do not assume this fits “any Royal Enfield with an O2 sensor.” Order only if your bike’s parts diagram shows 1020009/B or your existing sensor matches by photo/connector.

Variants
No variants.

FAQs 

Q1 (Fitment): How do I confirm 1020009/B fits my Interceptor 650 or GT 650?
Match your existing sensor to 1020009/B using a parts diagram (VIN/microfiche) or compare the connector + wire length + sensor body with photos. Dealer fitment pages explicitly list Interceptor 650 and Continental GT 650.

Q2 (Fitment): Will this work on Euro 4 and Euro 5 / BS variants of the 650 Twins?
Multiple seller fitment lists include Euro IV and Euro V trims for the 650 Twins, but market-specific harness routing can differ—confirm by connector/photo before ordering.

Q3 (Comparison): Genuine (OEM) vs universal aftermarket O2 sensor—what’s the risk?
Universal sensors often mismatch connector pinout, heater resistance, or wiring length, causing persistent MIL lights or incorrect fueling. Genuine part number matching reduces compatibility risk.

Q4 (Installation): Can I replace the lambda sensor at home?
Yes, typically with an O2 sensor socket/spanner. Let the exhaust cool fully, avoid twisting the harness, and route the wire exactly like stock. If the exhaust is modified, verify the sensor bung position and clearance.

Q5 (Symptoms): What problems does a bad lambda sensor cause?
Common symptoms: check engine light, poor mileage, hesitation, hunting idle, uneven throttle response, or fueling issues after water damage / wire cuts / sensor contamination.

Q6 (Returns-prevention): What should I share to confirm before dispatch?
Send (1) bike model + year/market, and (2) a clear photo of your existing sensor + connector (and ideally the part number from your microfiche). This prevents wrong orders on similarly-looking sensors.