Volkswagen Is Ordered to Recall Nearly 500k Vehicles Over Emissions Software

Agree that it's totally counterproductive to remove an upstream O2 sensor for a road application. (For an off-road application, the only reason is to allow the use of TEL (leaded) fuel additive as an octane booster and an open loop controller and any such application would drive so few miles per year that it doesn't need to be worried about. The reason to eliminate a downstream is to remove (or dramatically reduce) the catalyst function. I have not experienced a car that did a "compare downstream to upstream"; I'm sure they exist, but manufacturers have an incentive to reduce nuisance MILs, so most controllers are designed to detect gross defects and typical failure modes of installed components, assuming all specified parts are installed, not to detect all possible types of intentional tampering.

I agree with you that this isn't a significant issue in terms of pollution levels, as the enthusiast market that will mod their cars to this extent isn't large in numbers, but based on the amount of poorly modified cars I see (gassers with tailpipes so sooted up they look like diesels, diesels modified so they can better "roll coal", people who think "more fuel must be better" when changing ECU maps, etc), I wonder how many regular cars' emissions are equally by some of these poorly modded enthusiast cars.

(I love and have no philosophical objection to auto enthusiasts and modded cars. Despite my hands-on experience above, I now drive an electric LEAF, which is not exactly an enthusiast car, but does payback the environment for some of my youthful transgressions...)

I understand the point you are trying to make, and perhaps I wasn't very clear in my off-hand comment. I agree that overly loud bikes are annoying, however, as I stated before, sound is a necessary evil[0].

Do I believe that motorcycles should use straight pipes and increase their sound output? NO, in fact its quite annoying. However, louder bikes will get your attention.

In fact, in reference to [0], there is a standard that some vehicles had to INCREASE their decibel output because of less risk to pedestrians. This isn't an apples-to-apples comparison as this study was mainly geared towards electric vehicles, but it did state that vehicles should have an output of ~ 55dB for pedestrian safety (page 102).

Secondly, I couldn't find good stats on motorcycle decibel output, but I did find a study of some motorcycles and their average output[1]. What I learned is that most bikes are fairly equal with regard to output and all are at, or above the, legal limit[2].

I took a single bike you pointed out `Honda CBR250R` and was curious how the noise output performed to a Harley: `Honda CBR250R`: [3] - With dB-Killer fitted: 86 dB @ 4,250 rpm - Without dB-Killer fitted: 94 dB @ 4,250rpm

2006 Softail Standard 1,400 cc: [4] - 97 decibels at idle - 102 decibels at cruising speed - 111 decibels revved

So what it appears to me is that most motorcycles are `roughly` the same decibel output and that having a vehicle that outputs sound to make yourself known to other riders is beneficial. Should you be increasing the sound trying to be cool? No, I don't think so. In fact its annoying when the 5 Harleys are sitting outside my window on Friday night revving their engines to be "cool".

[0] - http://www.motorcycledaily.com/wp-content/uploads/2013/01/Qu... [1] - http://audiologyworld.net/img/rnhposter.pdf [2] - http://www.gencourt.state.nh.us/rsa/html/XXI/266/266-59-a.ht... [3] - http://www.autoevolution.com/news/honda-cbr250r-gets-street-... [4] - http://lic.abateflorida.com/Library/Library/cycle_news__nois...

I also agree that you don't have to make your bike EXTRA loud to be noticed but there is a perceived safety in sound. And if majority of the sound is exiting towards the back, there might a point to be made that the decibel level should increase to "hopefully" make the person in front of you aware.

You make a valid point "... implying that drivers have less need to perceive small bikes...or other cars, apparently."

As I stated above, but will re-iterate because its a valid reply here, there seems to be a necessary of roughly 55db produced by a vehicle to ensure safety for pedestrians and other vehicles. [0]

My initial comment was incomplete: it's not okay to have an extra loud bike to be "cool", however, it is important to have a high enough decibel output that other people can hear you. Most bikes produce similar dB off the manufacturing plant for a reason and electronic vehicles are required to output more sound to be safe.

So no, i'm not implying that drivers have less need to perceive small bikes or other cards. I'm implying that all vehicles should produce the necessary decibel output to bring attention to themselves.

[0] - http://www.motorcycledaily.com/wp-content/uploads/2013/01/Qu...