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Quiet Core Insert -> NOT QUIET! >=[

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Purchased a quiet core insert for my Procircuit T-4 which was supposed to bring the sound down to <96db. Just had it tested yesterday at a desert race and it blew <100db. The pipe only has a few rides on it, so the packing is still good. What's the deal with quiet cores? Do they all suck?

Guess I'm in the market for a stock silencer :banghead::applause:

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I put a Quiet Core in my PC4 (FMF) after I bought the bike (used). It reduced the noise a noticeable level! Havn't had it tested yet....

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lol it must suck to ride in CA where u can't have it as loud as u want :applause::banghead:

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Must suck to live in texas where there are no government run off road parks that are like 6,000+ acres. I'd rather have a quiet bike and a place to ride than a loud one and no place to ride. :banghead:

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I finally got to really try out the FMF powerbomb & Q silencer. Well..... it isn't so quite. It sure beats my old open Ti system, but that SOB still ruptures eardrums. No way in hell will it pass 96db, unless they only test it at idle.

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Must suck to live in texas where there are no government run off road parks that are like 6,000+ acres. I'd rather have a quiet bike and a place to ride than a loud one and no place to ride. :applause:

that, my friend, was a burn :banghead:

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Guess I'm in the market for a stock silencer :banghead::applause:

actually, the stock ktm silencer will give about the same air flow as a corked up t-4

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The Pro Circuit T4 and Ti4 are very loud exhausts.

For some reason, even with the supplied "spark arrestor insert" the exhaust still will not come anywhere near the required 96db limit for woods riding in designated OHV areas. You can, however, try the other PC end-caps for $25 that are designed to reduce sound. Use that with the insert and you'll have a better chance at passing the test.

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I finally got to really try out the FMF powerbomb & Q silencer. Well..... it isn't so quite. It sure beats my old open Ti system, but that SOB still ruptures eardrums. No way in hell will it pass 96db, unless they only test it at idle.

The problem with the powerbomb was that the steel wool packing used in the expansion chamber would burn up and render it's sound reducing capability to zero. The new megabom header is supposed to eliminate this and combine both the mx/sx performance characteristics.

I have run a few pipes on our (04) yz250f's, stock, GYT-R carbon fiber, FMF Powercore IV, Procircuit T-4, and lastly The FMF Q2, with the new FMF MegaBomb header. In all the best power was the Procircuit T-4, but at 5600 rpms it will bang the db meter at 105 dba's. the FMF Powercore IV has less power all the way thru and still bangs a decent 100 dba's. The GYT-R is a true waste of money. It actually kills power compared to the stock silencer. What a dog pipe.

The Q2 by itself with the stock header has good top end but deadens the low rpm range tothe point that you would swear your riding a 2 smoke. You have to stay on the pipe to make the bike move. With the oem header the Q2 bangs 97 to 98 dba's.

After adding the Megabomb header, it was obvious that they have designed them to work together as a system. They both work great together with really good revving of the motor from low to mid range and good pull thru the top end. Definitely better than the stock exhaust and way quieter. You will have to rejet (trust me on that one). The two together run 94 to 95 dba's.

Keep in mind all the sound reading are done on 04 - yz250f's that have high compression 262 big bore kits, and hotcams cams in them. They make at least 3 to 4 dba's more sound pressure at a given rpm than a stock bike. So if you have a stock bike, it's pretty safe to assume you can meet any sound limits with their setup and still get better performance than the stock exhaust. The dual exhaust of the honda's may prove that wrong in the end, but it will be a while before everyone will go that way.

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The GYT-R is a true waste of money. It actually kills power compared to the stock silencer. What a dog pipe.

Interesting. How so? Team Yamaha used them before the Carbon Pro came around.

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My Q only has less than 10 hrs on it. Its certainly not loud due to being worn out.

I do have a larger than stock cylinder, but I doubt that accounts for any extra db's

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Must suck to live in texas where there are no government run off road parks that are like 6,000+ acres. I'd rather have a quiet bike and a place to ride than a loud one and no place to ride. :applause:

I don't think we're "missing out" on places to ride :banghead:

IMG_0015.jpg

IMG_0004.jpg

IMG_0028.jpg

Name those tracks!

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I don't think we're "missing out" on places to ride :banghead:

IMG_0015.jpg

IMG_0004.jpg

IMG_0028.jpg

Name those tracks!

damn, that is a SICK track

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