Sound levels

[YUMASTEPSIDE]

What is the sound level maximum, where is it measured from, and how far away ?

                Roger

[frostype400]

I have heard some pretty loud bikes out there I am pretty sure it is 110 decibels to comply with foresty and road regs.

[frostype400]

Also pretty sure it is measured right up close to the end of the pipe too.

[lukeb1961]

"From 1st January 2009, the noise limit will be 96db(A) for 2 stroke engines and 94db(A) for 4 stroke engines"

http://www.ma.org.au/AM/Template.cfm?Section=MA_Reports&Template=/CM/ContentDisplay.cfm&ContentFileID=26209

[GD66]

And if you've got plenty of time on your hands, type Decibels into the 'search' facility at the top of the page...

[frostype400]

I dont know how they will enforce that at vinduro's unless they have a tester?

[YUMASTEPSIDE]

I have my own sound meter, so I would like to get it right before I turn up for an event.

                    Roger

[frostype400]

Plus as of 09 we are talking pre85 bikes where I thought in that era it was 110??? So they can't really knock you back on an event where you are running a stock one.

[LWC82PE]

I was researching some ADR rules this week and found that if you have a pre 88 bike it can be up to 100 DB for road use in SA. Also looked up the ADR numbers 28 and 33 on the PE compliance plate and one referrs to noise and the other to brakes.

[Colin Jay]

2010 MOM's (GCR's)

Chapter 12. All Disciplines
Rule 12.10.1.1
"Noise emissions must not exceed 2 stroke 96dB (A) / 4 stroke 94dB(A) unless a lower limit is provided for in the SR or another limit is shown in the table below:
...
Enduro & Reliability Trials 94db(A)"

There is no 2 / 4 stroke differentiation i.e. both engine types must meet a 94dB(A) limit.


Chapter 25. Enduro & Reliability Trials
Rule 25.3.0.1 "Noise emissions must not exceed 94dB(A) unless a lower limit is provided for in the SR or by the circuit hire agreement."

I doubt very much that you will have success with the "when the bike  was made / in the era noise limits". If they are doing official noise testing at an event, they will just point at the book and ask where it details any exceptions, if it ain't in the book, they won't want to know about it.

CJ

[fatboyracing]

Guys,
VMX Vinduro comes under the classic Motocross/Dirt Track banner and is covered by the noise reading of 96 db with an allowance of 2 db using a type 2 meter.
With some work these levels are reachable .

Cheers
Fatboy

[YUMASTEPSIDE]

.........OK, we're looking at 94/96db..........now, how is it measured ??

I remember something about "X" amount of distance from the rear of the bike............anyone know ?? Any scrutineers out there that know how its done ??

               Roger

[odd1]

I think 1 meter at a 45 degree angle from the rear of the exhaust also the engine has to run at a certain RPM don't know what that is.

[Mick]

My bike was done at 4,000 rpm

[fatboyracing]

Guys,
Bikes are measured at 500mm on a 45degree angle from the middle line of the exhaust end.
When testing unless you know your exact stroke I test at: up to 85cc 8000 rpm,85cc to 125cc 7000 rpm 125cc to 250cc 5000 rpm,251cc to 500cc 4500 rpm & over 500 cc 4000 rpm.
I have been a noise tester for 5 years and most vintage bikes fail the test because the muffler has never been repacked.It is easy to do and the results will amaze you how much difference a properly packed muffler will make.

If anyone has any questions about noise testing please feel free to PM me and I will try to help.

Cheers
Fatboy