E series Or fmf q core

I just bought a xr650r with an e series slip on. It is pretty loud . Should I try to take some discs out ? if so what should I run to be sound legal? or should I sell the pipe and get a fmf q core. I did not get the stock pipe with the bike.


With a header, E series running 12 discs and a quiet core insert I'm just legal at 96.0 db. From what I've heard the E series offers slightly better performance than a Q pipe.

Thank you !! I'll set up mine the same way

Hmmm... I have the Power Bomb header and the ProMeg E series pipe. With the end cap and 12 disks, it sounds way quieter than the stock pipe with the HRC tip. I'd think this would make 96 db easily.

Ramcc- what "quiet core" are you talking about for the e-series?

I am running 9 disk and it seems louder than the stock , uncorked can I Just removed. Not sure how proper db readings are taken but my cheap little radio shack db meter is showing over 98 db at 10 feet from the can(e series) off at a rearwrd 45 angle from the bike. the stock uncorked can show aprox 98 also. Not bad but definitly gets the neighbors attention when I fire up the bike, nice deep sound. playing around i could not get a reading under 96Db untill I drop to 6 or less disk and all the snappy response is gone at that point. Happy with mine.

Am I missing something? If you use the quiet core, you have to take the block-off plate out, right? Then the exhaust doesn't exit through the disks. Seems to me the exhaust pulses getting broken up and exiting through the disks is what quiets it down so much. I didn't sound-test mine but to my ears it seems way quieter than the stock pipe with the HRC tip-- almost as quiet as the drilled-out stock tip.

The quiet core is inserted into the pipe first, then the discs, then the end cap. The quiet core is definately worth the money to run 12 discs and still be sound legal.

Ahhh So! Grasshoppa... Now I undahstand!

I like the Supertrapp concept- it seems to work really well. Going back a couple decades, I had a street bike with a Supertrapp pipe where the disks were actually internal, and a Kerker-style reverse-megaphone tip. It sounded really sweet and was the best-performing pipe on the market at the time. I know flat-trackers and road racers still use megaphones for max horsepower... and the pipe ProCircuit makes for the Team Honda XR's are megaphones than neck down right before they enter a T-4-looking rear can. Anyone know why pipe manufacturers have gone away from the Megaphone design, other than noise? Is there a pipe with a megaphone design (like the ProMeg) that uses the supertrap disks, but internal instead of right at the end of the pipe?

Ramcc are you also running the spark arrestor so the gas is still forced to exit thru the disk? Doesnt look like the spark arrestor would fit, meaning the baffles are of no use and its just a big glss pack. Not picking a fight just trying to grasp

Yes, I still run a spark arrester. The quiet core installs like a disc & actually fits inside the can, if that makes sense. I wouldn't even consider running my bike without a spark arrester. If needed, I can take pics showing the quiet core installed in the pipe.

Gotcha, pic just looks like the small perforated pipe extends to far on both sides to have room for the spark arrestor, my stack of 9 disk is only aprox 1/2" thick. Does the can still have the nice deep sound? Thanks for clearing it up, gonna order mine today. :D

The quiet core defiantely changes the sound of the exhaust. I preferred the exhaust without it. IMO the quiet core gives the exhaust an airy/nasally sound. Many people have said they liked the sound of it, and it's really not bad, but it is noticeable.

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