Motorbike

[Rogue]

vwmaniac:
Additionally, loud pipes do make a difference, especially in city traffic between 25-45mph. I went a month with the stock can on my 929 because I felt it was too loud. I immediately noticed I was having more close encounters, people cutting me off, etc. I put the loud one on and will never go back again.

For over a year now, I've been riding a Yamaha Vino 125 scooter, which goes up to about 60mph and gets me up to 45mph rather easily. It's a four-stroke engine and so it's quiet. While people do occasionally cut me off, it's very rare and, so far, braking in time has not been a problem.

I did some digging around and loud pipes are actually more dangerous. According to the Hurt Report (1981):

There were modifications to the motorcycles in the 900 on-scene, in-depth accident investigation cases as follows:

8.9% had extended fork tubes,
1.3% had extensions with slugs.
8.2% had accessories, e.g., radios, tape, stereo, etc.
6.3% had saddlebags.
16.6% had luggage box or boot.
30.1% had modified exhaust systems.
4.1% had modified front wheel and tire.
19.9% had modified rear wheel and tire.
13.0% had modified rear suspension.
18.1% had elevated foot rests or highway pegs.
6.1% had modified triple clamps.
5.6% had frame modifications.
18.1% had crashbars.
27.1% had sissybars (but sissybars had no significant injury association)
24.6% had modified seats.
6.1% had modified gas tanks.
12.0% had windshields (with or without fairings)
2.4% had frame-mounted fairings.
6.3% had steering-mounted fairings.
Only one motorcycle was equipped with a sidecar.

In another dataset, modified exhaust systems were represented in 27.3% of exposure data. So, between 27.3% exposure and 30.1% of crashes, loud pipes increase your chance of having a crash by around 10%. Since the Hurt Report found intentional driver aggression to be very rare, it's likely noise fatigue on long rides which is causing the crashes. So while loud pipes may marginally help a car next to you to notice you, which is a comparatively rare cause of accident, overall loud pipes are more dangerous.

 

[ArcBound]

For over a year now, I've been riding a Yamaha Vino 125 scooter, which goes up to about 60mph and gets me up to 45mph rather easily. It's a four-stroke engine and so it's quiet. While people do occasionally cut me off, it's very rare and, so far, braking in time has not been a problem.

I did some digging around and loud pipes are actually more dangerous. According to the Hurt Report (1981):

In another dataset, modified exhaust systems were represented in 27.3% of exposure data. So, between 27.3% exposure and 30.1% of crashes, loud pipes increase your chance of having a crash by around 10%. Since the Hurt Report found intentional driver aggression to be very rare, it's likely noise fatigue on long rides which is causing the crashes. So while loud pipes may marginally help a car next to you to notice you, which is a comparatively rare cause of accident, overall loud pipes are more dangerous.

I read an engineering article that said when seatbelts were invented, the accident rate didn't really go down and stayed the same/went up a little. It's because people thought they were a lot safer with having the seat belt and therefore drove faster and more recklessly. The loudpipe thing might be something like that. The motorcyclist assumes that the car will hear him because of the loudpipe and drives a little bit more recklessly than the motorcyclist without a loudpipe and therefore tends to get into more accidents.

 

[Maxtro]

Also, in Cali 250's are not allowed on the freeway due to their lack of power.

False.

According to the California Motorcycle Handbook a "motor-driven" cycle is a motorcycle with an engine displacement of 149cc or less. Motor-driven cycles cannot be operated on a freeway. Motorcycles above the 149cc size are motorcycles as opposed to "motor-driven cycles" and can be operated on CA freeways.

Read more: http://wiki.answers.com/Q/What_is_the_minimum_size_motorcycle_on_California_highways#ixzz1KHDYgomR

 

[Bible_Belt]

Regarding loud pipes and safety, there really are a ton of intervening variables that make it difficult to say for sure. It is typically Harley riders who are the loudest, but in states like mine without helmet laws, they never seem to wear a helmet. Harley riders near me also do a lot of "poker run" charity events, where they basically bar hop all weekend. I see drunk, sunburnt rednecks, riding without a shirt, much less a helmet and real gear. By contrast, sport bike/crotch rocket riders, who usually have quieter pipes, almost always also have a helmet and often even an real riding jacket. But then they go and ride 150 mph through traffic like idiots.

In a state where everyone must wear a helmet, I would guess that loud pipe motorcycles are safer because they tend to be Harleys, which are slower bikes and typically ridden by older riders.