Loud pipes save lives!
Actually, no they don’t, and it’s because of the Doppler Effect.
The theory is, loud pipes automatically make the rider safer, because car drivers can hear there is a motorcycle present and will therefore drive more cautiously. However, the Doppler Effect mutes this.
The Internet has lots to say about the Doppler Effect, but here’s a nutshell summary from Wikipedia: “The Doppler effect … is the change in frequency of a wave … for an observer moving relative to its source … It is commonly heard when a vehicle sounding a siren or horn approaches, passes, and recedes from an observer. Compared to the emitted frequency, the received frequency is higher during the approach, identical at the instant of passing by, and lower during the recession.”
In other words, the deep, throaty roar of loud pipes isn’t really very deep or throaty until the vehicle has passed the listener. You can see the Doppler Effect in action in the first few seconds of this video, and see it explained below.
So you may hear a motorcycle approaching, but you won’t really hear much noise until it is next to you or past you.
Now, consider the definitive Motorcycle Accidents In-Depth Study from Europe, in which researchers found the vast majority of motorcycle collisions come from the front of the bike. That’s bad news for a motorcyclist, if he or she is relying on loud pipes as an Distant Early Warning system. The Doppler Effect means your exhaust could be creating a dangerous false confidence; by the time the car driver knows you’re there, it may be too late.
Prolonged exposure to noise can have very dangerous effects on a motorcycle rider.
Hearing loss will reduce your ability to perceive audible danger signs (sirens, mechanical problems, or vehicles in close proximity), and will also reduce your concentration (according to the US Dept. of Labor), as well as impair your “performance in spatial attention” due to background noise, according to this US government study from 2006.
This isn’t top-secret information. Riders have known about noise fatigue for years, which is why helmets like Schuberth’s C3 Pro or HJC’s RPHA Max are popular with touring riders: they greatly reduce in-helmet noise. Even if they don’t have pricey helmets, many riders at least wear earplugs when riding. So if safety experts inside and outside the motorcycle world know that loud noise can actually increase the risk of danger, why subject yourself to the blast of loud pipes? Even if the rider is spared the true noise thanks to the Doppler Effect, what about fellow motorcyclists, tailing behind on a group ride?
Statistics don’t back up the claim
Some riders will still believe they avoided a crash when a car heard their exhaust, and maybe that really did happen. But North America’s best-known study on motorcycle safety, the 1981 Hurt Report, found motorcycles with loud pipes were not less likely to be involved in crashes — if anything, they were a little more likely to crash. As the report states on page 421:
“The modified exhaust system was typical of many accident-involved motorcycles, and also typical of many motorcycles observed during exposure data collection. The modified exhaust is overrepresented in these data, but not with high significance.”
If you read the MAIDS report, nowhere in that report’s findings does it recommend loud pipes for safety. Instead, on Page 98: “The ability of the PTW (Powered Two Wheeler) rider to see and be seen is a critical element of PTW safety. As mentioned above, the largest number of PTW accidents is due to a perception failure on the part of the OV (Other Vehicles) driver or the PTW rider. The vehicle operator failed to see a PTW or OV. It then states outright that “The use of the PTW headlamp has been recognised as an aid to conspicuity,” but nowhere does it make a similar statement about loud pipes.
In other words, riders need to make sure car drivers can see them by turning on their headlight, not by turning up their pipes.
So who cares?
The public cares, and pissed-off citizens are slowly but surely mobilizing to fight against loud pipes. In recent years, city after city across Canada has started its own campaign to put an end to loud pipes. Edmonton, Vancouver, Calgary, Toronto, Bathurst, Saint John, St. John’s, and Kelowna have all taken first steps in the fight against loud motorcycles, to name a few.
Quebec City has actually gone so far as to ban motorcycles from the Old City, because of their noise. The rest of the province is in the middle of a five-year pilot project, with police officers using sound meters to check motorcycle exhaust noise in an effort to figure out how to properly measure exhaust volume. That data will be used to make sure lawmakers implement effective anti-noise legislation in the future (and raise ticket revenue while they’re at it).
And the public is irritated for good reason. Sam Blue is working on a petition in Saint John, N.B., to have police and lawmakers address the problem of “vehicles with their muffler removed and replaced with modified exhausts that are illegal, causing excessive emissions and noise.” Why? Because, he says: “Based on conversations I have had with other residents and business owners, it does factor into their quality of life. It impacts where people choose to live, and has an impact on businesses that depend on tourism and outdoor traffic, or dining on patios, and it also interferes with outdoor festivals or events.”
The former head of the Saint John police department’s traffic division remembers why the city publicly announced a crackdown on loud pipes back in 2001 — it was due to media coverage of the issue. Public pressure resulted in increased attention from law enforcement. As Jeff LaFrance recalls, it only resulted in a couple of tickets, one of which was thrown out in court, but public unhappiness over loud pipes results in riders being hassled.
So far, we’ve been lucky in Canada. Despite growing public frustration with loud pipes, we haven’t seen much punitive police action, at least in most jurisdictions (Quebecois readers might disagree). We aren’t seeing hundreds of exhausts seized and crushed, which does happen in other countries. But if the motorcycle industry and individual riders don’t realize where things are headed, we may enter a future in Canada where all owners of aftermarket or modified exhausts are punished, thanks to the actions of a few, and that’s something we don’t need — especially since those loud pipes aren’t saving lives in the first place.