Muffler pack for wr426 stock exhaust

6 replies to this topic
  • ttreewalkerr

Posted April 20, 2014 - 01:48 PM


I have a 2002 wr426, its very loud with stock exhaust. I removed the 3 bolts on back of muffler to see if I could re-pack,, looks like an empty chamber with not a structure that looks like it accepts pack. So my question is, do these take pack ?

  • C-R-M

Posted April 20, 2014 - 02:41 PM


I believe that is just the spark arrestor. Repacking the actual core takes further dissasembly. I'd refer to your owners manual.

  • ttreewalkerr

Posted April 20, 2014 - 03:37 PM


Looks like no pack in these, just chambers. Man stock muffler is loud. I see there is a plug for the end which is a stinger type tip, little quieter with that in.

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

Posted April 20, 2014 - 06:08 PM


Is there something like this picture in the end?  If not, it will be very loud.  With it, it's not as bad.  They came with something we call a pea shooter.  Very small and restrictive hole, everybody tossed it.  

The stock muffler has some packing around a mechanical baffle, not something they designed to be repacked.  You would have to cut it apart to repack it and weld it back together.  

I have an 01 wr250f which uses the same muffler.  I put an FMF megabomb and Q4 on it and it's quieter.  That was louder than I would have liked and needed to be repacked too often.  So I took out FMF's glass pack and welded in the stock baffle assembly from an 09 450.  Much better.  



  • Krannie McKranface

Posted April 20, 2014 - 07:31 PM


If it is repackable, the SERVICE MANUAL will show how.

  • jcbikes

Posted April 21, 2014 - 05:57 AM


I have a 2002 wr426 and made mine street legal. just like yours and too loud. I took out the spark arrester assemply (three bolts) and used steel wool to pack the whole inside. used a broom handle to compress it to the sides so that the spark arrestor assembly will fit back in. I have mine packed really tight and it has been working great for the past 4 years. You might have to adjust the carb because of the more restriction of the exhaust flow but it worked great for me. I used steel wool because I had some but you could just use muffler packing.

  • ttreewalkerr

Posted April 21, 2014 - 09:02 AM


Thx. I may create a cage to hold the pack against the outer wall. So it will be 1/2" of pack, and create almost no restriction.


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.