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Why do you think KTMs header is now larger?
Db limit dog
there is a huge push for bringing sounds levels down
I’ll ask again in here and maybe get a better answer. Why do we need to lower sound limits for professional events again?
You think people impacted by noise from events care if the participants are professionals?
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Long tube headers are a great way to add power, especially in the lower to mid range, people have been doing it for a very long time. In racing a benefit would be the ability to run higher gearing which smooths and stretches the power and allows less shifting around the track. Wide Ratio transmissions are great if you have enough power!
On the sound level, I don't think a longer header really does anything. You'd have to have a chamber for the gases to expand, which is what KTM appears to be doing.
Can you name the victims of San Diego SX? Who is the victim of the KTM test track?
Owen, I do not know your history here on Vital, but if you do not understand the need for lower sound levels, you are part of off road motorcycling’s very large and very real problem.
I’ll ask again, why do we need loud bikes? It’s been proven they can make decent hp at lower db limits so why damage our hearing for no reason?
Remember fellas, +3dB is twice the sound energy. Cutting 6dB from say, 105 to 99 is a massive reduction in how far sound carries.
Her name is Karen McKarenly. You name activity and she has surely been victimized by it. Sheesh, I thought everyone had heard of her.
Exhaust wave compression and rarefaction tuning.
Example I found online.
engr.colostate.edu/~allan/fluids/page7/page7.html
In SX, the events are in downtown areas with tons of ambient noise.
In Nationals, anyone living close enough to be bothered in all likelihood moved in long after the track was built, and can kick rocks.
Especially in supercross when the previous weekend had unregulated monster trucks at 150+ decibels.. For professional races sound shouldn't even be considered a problem. now every single weekend for regular riders and a lot more riders on those weekends, that makes sense to bring the sound down.
Yeah but you have 1 or 2 trucks going at a time vs 22 heading into the first turn.
Over 30 years ago I had some math from my notes from advanced 4 stroke class at MMI and had a company called Aircone make some mufflers. The pipes made more power, but was all top (and were way too loud),so out of sheer frustration I had the same insert and reversion cone made but reduced the core by 50 percent. I threw the math out and it was great! This thing is extraordinary, anybody got better pictures?
If push comes to shove the only people that will be kicking rocks is the track owners and riders.
There are some race's and training facilities that are more lax than others, they aren't the ones they are catering to.
4 strokes fault.. 2 strokes don’t make that far carrying noise that shuts everything down.
Pit Row
I've been around quite a few loud 2-strokes who's sound carriers plenty far to get complaints.
I didn’t say they need to be loud. Where did I say that?
I’m just confused as to how we’re docking points and threatening championships over muffler packing.
And there is way more down time during a monster truck show. One or two trucks at a time for less than 4 minutes, then 5 minutes before then next one. If there's a crash or breakdown then there's even more down time. They are loud as fuck though, we make the kids wear ear protection.
Yeah and once they spread out the max sound within 1 foot of those bikes is still only 115db...now step back 80 ft from the track where the first row in the stands is at a supercross. Now you only hear maybe 60db of sound...
Are you listening to yourself?
They don't need to be loud but they shouldn't be docked for being too loud?
This is exactly what I've ben thinking. Outdoors, yea. Sound.
Monster jam rolls in, as loud as they want... yet we need to quiet the bikes for professional racing?
It's a fair enough question to be asked.
I'm a bit naive here but..... is sound mitigation in our sport limited to making header pipes longer and oddly shaped? Just seems like there has to be noise reducing tech somewhere out there that could be incorporated into modern exhaust systems.
Motocross is one of the only professional motorsports where the general public can buy essentially the same equipment that is raced at the professional level.
Thus, quieter bikes at the professional level equals quieter bikes for consumers which means hopefully we can keep more riding areas open. It's literally that simple, it's a battle that we've been fighting for decades and is nothing new.
Before someone jumps in and tries to look smart and says "insurance is what's closing tracks" please realize this sport is MUCH larger than just motocross tracks. Most bikes that are sold will be ridden in farm fields, back yard tracks, some sand pit with houses nearby etc. etc. they will never touch a true motocross track. I know that's hard to fathom when you are hardcore moto enough to be on a forum like this but it's the truth. Having quieter bikes helps keep those places open.
As well as the Long, 'out of frame' Header, Gajsers bike has 2 Helmholtz Chambers, one on either side. You do what you need to do, to have power, while passing sound regs.
Sorry, small, blurry pictures:
Yeah loud and clear actually.. life is not black and white genius. Bikes don’t HAVE TO be loud. They can be, or they can’t be. We’re just talking about the need for professional sound ordinances. I didn’t say they need to be open header dude use your brain.
You got your answer multiple times in the other thread you asked the same question in....
Thanks, I'm not criticizing it, I'm amazed by the effort
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