With a name like SlapDrum and being an engineer....
Ooh yea.. I have a meter. (They are not too expensive anyway)

I thought, "hey these guys might appreciate this info"
So I attached the data sheet as a jpg.

To give a little relative values to the data.
Playing the SlapDrum.com Cajon peaks at 83.5 dBA
My 14 year old yelling "Dad!" peaks at 95.7 dBA
Sitting quiet in the office is 38 dBA
Me talking at a regular voice is at 60 dBA
Hope that helps.

Chris

 

are those readings with the vortex insert in?

 

great info. your going to go def dude, getting those levels from the kid and the bike.

 

Good information!

 

Sunday I took it for a 40 mile ride. Holy Cow! that is loud.
There is a flaw is the test design. I need to be able to measure dBA while underload at those RPM's.

I have read that some use the KLX300 Header and Exhaust.

- Anybody know if that fits the 2009 model?
- Anybody have pictures of that KLX300 Exhaust?
- Any info on how loud the KLX300 is?

I like the power and feel, but after you exceed 5K-6K RPM it does start to annoy.

OK whaa whaa whaa, I'll quit belly aching and I'll see if it grows on me over the next couple weeks.

Did I mention the Snappy power is great

Let me know if you find any KLX300 exhaust info.
Thanks, SlapDrum Chris

 

EMS, Yes the Vortex is "In" during the test.

 

Are those readings with the engine under load? or taken "non-loaded" by just turning the throttle with the bike in neutral?

It makes a HUGE difference due to throttle position.................

 

wonder how loud the two bros is?

 

Sound testing is done so many inches away from the exhaust tip at a 45 degree angle no load @ a certain rpm in an open area, detailed protocalls are followed.

The stock exhaust has stamped into it 80 dba max. Wonder how you got that high of a reading.

The wife hated her 2 bros M7 until the P3 insert was installed.

 

If you search, you'll find the noise test that I did in three confogurations; stock, with the HMF slip-on and the HMF w/ quiet core. The generally accepted test standard is SAE J1287, which is basically as RaceGass states; but specifically with the meter at the outlet elevation @ a 45 degree angle from the bike centerline at a distance of 20" from the outlet. This should be done in an open area, away from hard noise reflective surfaces, on blacktop. The engine is to be in neutral at 1/2 the rated RPM - so for the KLX it is 5,250 rpm.
If we all test to the criteria in this standard, we will have apples to apples tests, can post the results and can then decide how loud we want to go.