96 decibels ???

Anyone know if my STOCK 2011 yz450 meets that sound requirement ? Wana do some events that require that number (96 db ) on their sound tests

AMA Amateur sound levels are 94 db for 2011. They gave the OEMs almost three years notice so they could incorporate this new sound level into their design cycle.

You should pass 96 db easily as should the majority of 2011 bikes.

From MX Action:

(4) Sound. The 2011 Yamaha YZ450F produced an AMA-legal 94.5 dB. It did not pass the FIM’s two-meter-max test, but no Japanese-manufacturered 450 has in 2011. It blew 117.4 dB when wide open.

I have a 426 that I want a green sticker for

wondering if packing it myself (it does need it anyway) or just buying a whole new pipe with the spark arrester and be done with it !

I have a 426 that I want a green sticker for

wondering if packing it myself (it does need it anyway) or just buying a whole new pipe with the spark arrester and be done with it !

What kind of "green sticker" are you talking about?

As for a 426 passing a test... I have an HMF comp series with three inserts wide open closed a little and quiet core... My bike only passed with the quiet core installed, and lets just say that was considerable loss in power.

Unless something has changed very recently, the YZ426 will get a green sticker just by registering it as an ORV. There is no sound test.

Certain trail areas, however, do have additional requirements regarding noise, and most of those kinds of managed areas in California require spark arrestors. The safest bet is something on the order of a Q4 muffler.

Unless something has changed very recently, the YZ426 will get a green sticker just by registering it as an ORV. There is no sound test.

Certain trail areas, however, do have additional requirements regarding noise, and most of those kinds of managed areas in California require spark arrestors. The safest bet is something on the order of a Q4 muffler.

+1 Thats what I was getting at. Mine is greeeeen!

On a somewhat related note the SX teams get their db tested with a very temporary slip-on unit (that is not even bolted on) just to pass sound testing. They then immediately go back to the pit and put on their much louder better performing lighter silencer. The AMA turns a deaf ear to this process.

deaf ear lol

117 is seriously loud though, I wear hearing aids and some of the exhausts drive me crazy, quads seem to be worse around here, I had to wear earplugs at the atlanta supercross this year

I wear hearing aids and some of the exhausts drive me crazy, ...

See if your vendor can crank down the compression/clipping on those. Wearing mine is no problem in loud environments. They won't pass any more than a set level of output.

I pull them out when I ride or I'm around bikes, the aids are not what bother me

Hmm. I ride with mine specifically for the noise limiting capabilities they have, along with the ability to hear semi-normally when called for.

everyone I ride with knows to yell at me

On a somewhat related note the SX teams get their db tested with a very temporary slip-on unit (that is not even bolted on) just to pass sound testing. They then immediately go back to the pit and put on their much louder better performing lighter silencer. The AMA turns a deaf ear to this process.

I don't agree with you on the deaf ear deal. The AMA puts identifying marks after they test the muffler on the end cap. If racers get caught with a can that hasn't been through sound there will be hell to pay.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now