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I never had it measured directly, but I ran numerous track days at Laguna Seca with the stock exhaust, where they militantly enforce a 90dB limit, and I never got flagged for sound.
No, I didn’t take it easy through turn 5 and up the hill where the sound is measured.
 

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Discussion Starter · #3 ·
I never had it measured directly, but I ran numerous track days at Laguna Seca with the stock exhaust, where they militantly enforce a 90dB limit, and I never got flagged for sound.
No, I didn’t take it easy through turn 5 and up the hill where the sound is measured.
Thanks looks like ill have to run stock also, to get through the db checks
 

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2014 1190 RC8R
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Is "sowing machine" a decibel reading? Lol

Everything aftermarket I've heard on these bikes is probably not going to be allowed, or cut it very close at the very least.
 

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Discussion Starter · #5 ·
Jester exhaust is running 97. 98 db on idle......limit here in sweden is 95db at test rom 5000 or 5500 depending on track..had an idea to double up silencer if possible, for example extend the jest using a link pipe and add a side mount exhaust....

No idea if that is even possible...maybe if the jester silencer box is shortened it could be possible.
 

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Jester exhaust is running 97. 98 db on idle......limit here in sweden is 95db at test rom 5000 or 5500 depending on track..had an idea to double up silencer if possible, for example extend the jest using a link pipe and add a side mount exhaust....

No idea if that is even possible...maybe if the jester silencer box is shortened it could be possible.
i m pretty sure you can make your own custom extentsion for it. You need to dril the rivets out and then make a new end cap with the extension.
 

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KTM 690 Duke Street Tracker
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Depending on country and year of manufacture 83-95 db is common. And as it’s not based on stationary noise test it includes drive train, induction and transmission noises. In a drive by test. There usually is a secondary test data requirement chart that acts as a guide for law enforcement to test at 45* and 2 mtr from the muffler opening, at a specific rpm. This just allows them to ticket for excessive noise and perhaps enforce a muffler tampering inspection. That’s how it works here in Australia. Various states local law enforcement are instructed how they should prioritise federal laws. Mostly relaxed in my state, not so nice across the border
 

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Maybe the North American bikes are different regulations, mine shows 80 db @ 3500 rpm.
102548
IMG_9445.jpg
 

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It might be that the method of measuring is not the same as EU, probably further distance and different angle, RPM.

My stock RC8 exhaust is about 86dBA at 2 metres, 45 degree angle, idling about 1750 RPM.

The JCE exhaust was about 89dBA same method, and with a big bad bass tone, sounded like a helicopter.

In the end I put the stock exhaust back on, the JCE was about 6kg lighter but way too loud, I had to wear earplugs every ride.

I tried repacking it, but it made little to no difference.
 

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I just checked my one and it says 100db at 5000rpm. Mine is a KTM RC8 (non R) if that makes any difference
 

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Discussion Starter · #17 ·
It might be that the method of measuring is not the same as EU, probably further distance and different angle, RPM.

My stock RC8 exhaust is about 86dBA at 2 metres, 45 degree angle, idling about 1750 RPM.

The JCE exhaust was about 89dBA same method, and with a big bad bass tone, sounded like a helicopter.

In the end I put the stock exhaust back on, the JCE was about 6kg lighter but way too loud, I had to wear earplugs every ride.

I tried repacking it, but it made little to no difference.
Measure at 1/2 meter 45degrees at 5000
 

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what izzat? 3 mufflers welded in series?
 
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