by pacomotorstuff » Thu Apr 20, 2017 8:16 am
I just finished reading through the whole 3 pages of the “noise” issue posts again and have a some things to add. Maybe a lot of you would like me to shut up or just not post ‘cause I’m not racing anymore so it’s "none of my business", but here goes anyway:
1, I want to apologize for my earlier “inappropriate” post. It just made me see red, when all of our great volunteers – Peter, Greg and Ashton, just to name a few – were / are getting abused, bigtime. I’ve held various posts, including director, in a number of volunteer organizations and let me tell you, continued abuse of the people that make it happen is the quickest way I can think of to make them quit.
Shame on you if you continue to do so; perhaps you should consider joining another racing organization where you feel more “welcomed” – or become a VRRA volunteer yourself and help out.
2, I was probably one of the first people around that did motorcycle sound testing – back in the late ‘70’s, believe it or not. I was involved in off-road motorcycling and was concerned our club was going to lose their riding land due to noise complaints (which they did). FYI, we had a set methodology to follow – can’t remember if is was an ASTM or SAE standard spec, it being nearly 40 years ago - and the loudest bike that day was a full-on race TT500 Yamaha, which managed to pull a stunning 115 dBA on the meter.
3, dBA / noise readings are measured on what is known as a “logarithmic” scale – they’re not a linear plot. Example, 90 dBA is HALF AS LOUD as 100 dBA and 80 dBA is ONE QUARTER as loud as 100 dBA.
So when someone says that they only want a 10 dBA reduction in sound, what they are actually saying is they want the noise CUT IN HALF.
4, looking at the standard test methods, it becomes apparent – unless a particular track has their own test method, high exhaust systems will tend to read louder due to the test location of the microphone.
Temperature and humidity, background scatter noise, wind direction and even where the bike is tested, all affect dBA readings. How each meter is calibrated and the frequency of calibration is important. The rpm thing is so obvious, I shouldn’t even have to mention it. I think the Calgary Police Department had 100% of their noise tickets thrown out of court due to their ignorance of test procedures.
5, the higher pitch of a two-stroke engine running may seem “louder” to the human ear than a four stroke at equivalent dBA readings, as pitch is not measured.
6, yes, it is a shame that the Rudges et al will have to be muffled up and won’t be period-correct now, but I suppose you could say the same about oil containment pans and a bunch of other safety improvements our club has mandated over the years. If we go to the other extreme - the bikes must be exactly the way they were raced back in the day, you might find yourself in the same boat as a friend of mine who waited 3 years for the correct carburetor so he could get through tech with the club he raced with.
7, about a year ago, I did some work on a modern race bike that had recently returned from racing in California, at a “name track” with a “name rider” on it. I was looking at the titanium can on the exhaust system, which was drilled full of holes for sheet metal screws holding in wads of steel wool. Failed the sound check with the exhaust system that was used in Canada and this was the only way tech would let the guy ride, no matter who he was or who he rode for. So yes, it can happen to you, too.
8, as I said, I’m not racing anymore (but am probably the biggest fan there is of all you racers), but if I was and someone told me to put a muffler on my bike if I wanted to continue racing, seems like a real no-brainer to me.
I’ve been involved on and off for decades in a number of different industries where noise and noise abatement have been huge issues and can tell you that the millions of dollars spent on noise reduction make the issue of a non-standard muffler on your race bike seem like pretty small beer to me.
Thanks for reading this.
Pat
