Modified silencers: the law, the fine, the social cost
TL;DR
- Your vehicle's silencer must stay the one it was approved with. Fitting a louder aftermarket exhaust is illegal.
- Rule 120 of the CMVR sets the noise ceiling (broadly 80 dB for two-wheelers, 75 dB for cars); altering it is a separate offence.
- Expect layered penalties: 1,000 to 2,000 rupees under Section 190(2), 5,000 for the alteration, plus seizure of the part until you refit a legal silencer.
- The fine is the small cost. The seizure, the refit, and the street's lost sleep are the real ones.
Contents
The rule
Your vehicle must keep the silencer and exhaust it was type-approved with. Swapping in an aftermarket silencer that makes the bike or car louder is illegal. Under Rule 120 of the Central Motor Vehicles Rules, 1989, every vehicle must carry a silencer that holds noise within the prescribed limit. That limit is broadly 80 dB for two-wheelers and 75 dB for cars. Altering the exhaust to be louder is a separate offence under the Motor Vehicles Act.
Why this rule exists
Two reasons. Noise: a modified silencer adds nothing the engine needs; the extra sound is the entire point, and it lands on strangers. A loud exhaust at 95 to 105 dB, passing a bedroom window at 1 am, wakes a whole street. Emissions and safety: the stock unit also carries the catalytic converter and the back-pressure the engine was tuned for. Strip it and you raise pollution and, often, the risk to yourself.
What happens if you don't follow it
The penalties layer up:
- Section 190(2) of the MV Act (driving against noise and emission standards): 1,000 rupees for the first offence, 2,000 for a repeat.
- Section 52 read with Section 182A (altering the vehicle from its approved specification): 5,000 rupees per alteration.
- Police routinely seize the modified part and hold the vehicle until a compliant silencer is refitted. In city enforcement drives, combined challans have crossed 10,000 rupees.
Quick reference
- Legal: the silencer your vehicle came with.
- Illegal: any aftermarket exhaust that raises noise past the limit, removes the baffles, or drops the catalytic converter.
- The fine is the small cost. The seizure and the forced refit are the real ones.
- Be the rider whose bike nobody hears three streets away. The engine gains nothing from the noise; the street loses sleep.
Quick check
1. You have fitted an aftermarket loud exhaust to your bike. Which statement about the law is accurate?
Select an answer.
2. Beyond the challan, what is the strongest practical reason to keep the stock silencer?
Select an answer.