g'day,

got a analogue decibel meter and tested out my short shots. (stock baffles)

this is by no means a professional meter and i didnt follow any type of standard or official testing format, just wanted a ruff measurement of the sound.

I tested it in an open, empty car park. tested the background noise first and the highest reading was a car comming down the road reading 6 db, which wouldn't effect any of the readings.

took the first readings with the bike on its stand ildling, i was standing on the right side of the bike holding the meter about mid body.

standing next to- 111 db

standing about 5m away- 102 db

standing about 20m away- 95 db

holding meter directly behind exhaust- 124 db

holding directly behind exhaust with 3/4 to full throttle- 125 db- 128 db? (meter only reads to 126 db)

did a couple more test while riding and took readings with it just sitting on my lap.

cruising- 115 db

highest reading putting on the throttle- 124 db

will be installing the quiet baffles soon and will run the same tests and see how it goes.

cheers

 Just what Ive been looking for, where did you get the meter from ???

was standing 90 degrees to the exhaust, will go 45 next time.

will try it with the weight setting to "A", just playing around with it at the moment and getting a ruff jist of it. im guesing using the "A" setting will read slightly less than "C".

got this one through ebay wayne, not expensive at all.

if you want a more accurate reading i would get a proffesional digital one and calibrate it.

I will give it a go on the 'A' setting. it dose say in the setting procedure to set weight to A, if you want to measure noise level or C, if you want to measure sound levels of musical material.

here's what was on the instructions-

RESPONSE
the response selector has two settings: fast and slow. in the fast position, the meter reacts quickly to changes in the sound level, showing you the peak sound levels present in the enviroment. in the slow position, the meter is damped and indicates an average-value sound level. the effect of brief sound peaks is minimized in this position.

WEIGHTING
set weighting to weight the sound measurement for a particular range. when set to A, the meter primarily measures frequencies in the 500-10,000 Hz range, which is the area of greatest sensitivity to the human ear. when set to C the meter measures uniformly over the frequency range from 32-10,000 Hz, giving an indication of the overall sound level.

MICROPHONE
the meters built-in microphone works best when you piont it directly at a sound source.

just gave it a quick go on the driveway to see the differance between the two settings and your right, they are totally different.

C' setting was peaking at 112 db and A' setting was peaking at 95 db.

95 db is under the leagl limit isn't it? short shots are definitely not legal. fuck, i dont know what the go is?

wasn't testing to see if they were compliant guys, I already know there not. anything not stock is not compliant. i know ill get done with them, its just a matter of when? (thats why i have my stock ones ready to go ).

I just wanted to know how loud ruffly the actual fuckers are.

went back to the car park and went for a short ride and tested again on both settings.

standing (45 degree)-

A- 94 db, C- 111 db

cruising (in lap)-

A- 101 db, C- 115 db

throttling it (in lap)-

A- 119 db, C- 124 db

thanks for the link thruster, will give it a go tomorrow when i can get an "assistant" to help me out. i can only test at idle by myself.
i dont have a tacho, so how much throttle should i give it when testing?

well, tested again and did it the same way on the link posted



got 104 db

emailed vance & hines and ask them what they rated to see if i was in the right ball park and if the meter is actually working properly. there answer was 103-104 db, so after a bit of mucking around and help from thruster i got it right in the end.

was about 95 db at just idle.

once i put the quiet baffles in ill test again.

looking forward to see the diff the baffle makes... being a 2dB baffle thats all it should drop by.

What RPM are you doing the tests at? This would make a difference.

wouldn't have a clue, cant tell.
just giving 1/4 throttle.

yeah, on me sticker it says 2650 RPM but i have no tacho yet so just winging it at the moment.

I was talking to a transport cop in Ballarat about another matter the other day. I asked him about noise and harleys. He said he doesnt bother pulling them over as its a waste of his time He takes the rego and reports it to the EPA. Apparently if the EPA gets a couple of reports on your bike you are sent a letter asking you to bring in your bike for testing. (of course if you got the letter you would change the mufflers before you went in, wouldnt you)

I think we all know it that aftermarket pipes are all over the limit regarding decibel reading. However I'm enjoying your experiment Whitey.

One thing that I have pondered is, are riders on Softail and Dyna's looked upon as more likely to be breaking the law. To me the ignorant public look at all the smaller bikes as the ones favoured by bad boys, whereas the RoadKings and Ultra's are looked upon as being owned by more conservative bikers. If you know what I mean.
I now feel less of a target (for cops) riding around on the RoadKing,especially so if we are travelling 2up. Whereas when I had the Softail with the lean mean look I used to get noticed more by the LAW. However, both bikes had illegal pipes.

Maybe I'm just living in hope........TC

well put the baffles in yesterday.

it mad a big differance, to me it did anyway. took that annoying high pitch crackle out of it and set the tone deeper, just right.

recommend to anyone that the baffles are the goods, nice tone with still plenty of bark.

gave it another test and it turned out what to be expected.

was sitting between 103 - 104 db.

idle was about  94 db.

cheers

thanks mate... sums up what I had heard. The main change is the additional back pressure it provides which changes the tone and gives a little more hp.

it is in fact not a 2db baffle (in the true sense)... just supposed to reduce the noise by 2db.

no worries skull,
the high readings was when i was fucking around with it.
i was using the 'c' weighting and sticking the thing right up to the exhuast outlet, and the other time was sitting in lap and the read-out would of been mostly wind noise anyway.

I saw that exact model today somewhere for $23 usd delivered. Might need to check through my cache and maybe grab one since they seem to work.