WR 426 Noise in dbs

I took my bike(02 WR 426) with a full white Bros. exhaust yesterday to the bushwackers race at praire city to have it sound tested so I can race it in san jose at metcalf in 2 weeks.Well I took out as many discs as possible down to 4 and the quiet core it registered 102 on the db meter .The guy told me this is the hardest bike to keep quiet him and his friend worked like 2 months on one to get to 96 dbs.I guess what I want to know is?Does any body have a 426 that they have at 96dbs what pipe and how does it run still run as good if jetted right. :banghead: I just would like to race it in the cross country class if possible. Thanks Jeff

I run the stock pipe. I have no idea what my jetting is.

I removed the stock baffle and put in a "Quite-is-cool" tip.

Last race I tested at around 90 to 92db.

Good product, easy to install and my bike actually runs better with this tip than it does uncorked. :banghead:

Here is a link to their website: http://www.quietiscool.com/

Quiet002a.JPG

These guys also make a shield that fits over the E-series discs. It's on their website.

These guys also make a shield that fits over the E-series discs. It's on their website.

I have an E-Series on my WR400. I run 10 discs with the quiet insert and the Quietiscool shield. The bike still does not come anywhere near 96 dB.

I had a WR426, it has the vortip and I also used the GTYR, the GTYR was at 93 db, the vortip was 91. I now have a WR450, FMF Powercore4 witht he quiet core insert and it runs 94 db. Powercore4 without the quiet core is over 100db.

I had a WR426, it has the vortip and I also used the GTYR, the GTYR was at 93 db, the vortip was 91. I now have a WR450, FMF Powercore4 witht he quiet core insert and it runs 94 db. Powercore4 without the quiet core is over 100db.

How much of a power loss do you experience with the quiet core.

FMF Q - I have a 450 that I run with stock header and stock jetting, I registered 92 at a race last weekend. My buddy has a 426 with the power bomb header, (he plays around with his jetting), but it is equally as quite as mine. Performance wise? I manage to eat the orange 450's all day long and I can run with YZ's and other WR's that are louder than mine no problem. I've heard alot of smack talk about the Q's but I have been extremely happy with mine for two years. I have a 99 WR 400 with the E-Series pipe and I have the same problem, I am down to 6 discs and it's still to loud. Try re-packing........

Ya I tried to repack it and tryed the Q insert and four discs and still 102dbs so I am going to try the new E-2 its a lot longer that my other pipe so hopefully I will be racing next weekend We will see thanks for all the help its nice to see you can get the dbs down on these bikes.

How much of a power loss do you experience with the quiet core.

Not sure, I have never ran the Powercore without the quiet core insert. I installed the powercore and insert all at once and over stock, huge improvement. It has a nice sound, throaty, "commands respect" type of sound. :banghead: You know the sound, the type that makes other riders pull over and let you through.

As in stock, you meant the stock muffler with the gytr insert correct? Not the stock pen sized insert :banghead:

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