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In Minnesota, the noise law for Motorcycles defers to the Pollution Control Agency's noise limits, which is 83 dB measured from 50 feet using the A scale with a dB meter (for motorcycles manufactured after 1975). I was curious if the Termi exhaust is actually considered noise legal where I live, without the chirping dB killer. I decided to measure the levels on the street outside my house, and also got a few strange looks from people out on walks. 
I set up worst case scenario with the Termi pointed directly at the meter 50 feet away (most tests are from the side, which should be a bit quieter). Here are the results:
Idle: 70 dB
4000 RPM: 76 dB
6000 RPM: 78 dB
8000 RPM: 84 dB
My meter works by setting 0 to 60, 70, 80, 90, 100, 110, or 120 dB, and then it'll measure -10 to +6 dB from 0. I had 0 set to 80 dB, so the lowest it could read was 70 dB and the highest it could read was 86 dB. When I hit the fuel cut, the dB's jumped up over 86 dB. That doesn't really matter though, because for vehicle noise measurements, they don't measure red line.
So unless I am literally bouncing off the rev limiter, it's well within the PCA's noise limits. I'd consider the Termi to be a completely legal motorcycle exhaust in MN. Other states and countries will vary, but it does appear to be within the limits of most states. The distance for measurement is usually 50 feet, unless it says otherwise. Here is a list of states and their laws: Motorcycle Noise Limits
Here is a video of the meter:
I set up worst case scenario with the Termi pointed directly at the meter 50 feet away (most tests are from the side, which should be a bit quieter). Here are the results:
Idle: 70 dB
4000 RPM: 76 dB
6000 RPM: 78 dB
8000 RPM: 84 dB
My meter works by setting 0 to 60, 70, 80, 90, 100, 110, or 120 dB, and then it'll measure -10 to +6 dB from 0. I had 0 set to 80 dB, so the lowest it could read was 70 dB and the highest it could read was 86 dB. When I hit the fuel cut, the dB's jumped up over 86 dB. That doesn't really matter though, because for vehicle noise measurements, they don't measure red line.
So unless I am literally bouncing off the rev limiter, it's well within the PCA's noise limits. I'd consider the Termi to be a completely legal motorcycle exhaust in MN. Other states and countries will vary, but it does appear to be within the limits of most states. The distance for measurement is usually 50 feet, unless it says otherwise. Here is a list of states and their laws: Motorcycle Noise Limits
Here is a video of the meter:
