96db with R4 and Quiet Core II Insert?

2 replies to this topic
  • bloussant

Posted February 08, 2006 - 02:18 PM


I've got an '01 YZ426F with a White Brothers R4 muffler, and it's pretty loud....guessing over 100db's. WB makes a Quiet Core II insert that's advertised to quiet it down 5-6 decibels. Anyone try this out and pass the 96db test? If not, any other ideas to get the R4 and YZ426 to pass the 96db test, or should I just give up on the R4?

Visit the ThumperTalk Store for the lowest prices on motorcycle / ATV parts and accessories - Guaranteed
  • 642MX

Posted February 08, 2006 - 04:37 PM


R4's was probably the loudest pipe made. I think you will have to upgrade pipes to meet a 96 db test.

  • xjruss

Posted February 08, 2006 - 06:02 PM


I have the same issue... bought my 426 used with the R4 on it. Can you still get the quiet core insert for that model/year pipe?

Related Content


Thinking about Yamaha 250... by Arctic Pride

Dirt Bike   Special Interest Forums   Pro Racing
  • Hot  491 replies

Megabomb Fitment by 288yz450

Dirt Bike   Make / Model Specific   Yamaha   YZ 400/426/450
  • 1 reply

2016 YZ450 by CaptainKnobby

Dirt Bike   Dirt Bike Technical Forums   Suspension
  • Hot  59 replies

Snake pit oct 30th by The Anvil

Dirt Bike   Dirt Bike Regional Discussion   California
  • Hot  293 replies

yz250x vs 450 4t comparisons (preferably desert riding) needed by JakeNorthrupYZ450F

Dirt Bike   Make / Model Specific   Yamaha   Yamaha 2-Stroke
  • 9 replies

Join Our Community!

Even if you don't want to post, registered members get access to tools that make finding & following the good stuff easier.

If you enjoyed reading about "" here in the ThumperTalk archive, you'll LOVE our community. Come join ThumperTalk today!

The views and opinions expressed on this page are strictly those of the author, and have not been reviewed or approved by ThumperTalk.