I ran some sound tests on the 05 WR450 exhaust

Hey gang,

For those of you interested, I just got done running some crude sound measurements on my 05 WR450 exhaust.


Cold(35°F), damp, overcast, 15 mph breaze, open field (nearest building 75ft).

I used a calibrated B&K sound analyzer "mediator 2238"

This is not a cheap radio shack model, we are talking a $5k machine I borrowed from work :) .

As far as professional analyzers go it's still the bottom of the line :) .

All tests were performed per the SAE J1287 standard.


No insert, No SA, No tail cone/cover WIDE OPEN CAN = 100 to 100.5 Db

No insert, SA installed, tail cone/cover installed = 96.5 Db

No, insert, No SA, Just cap/cone installed = 97.8 Db

"modified insert", SA installed, tail cone/cover installed = 94 to 94.5 Db

This is a link to what my cone shaped "modified insert" looks like.



Sorry to hijack your thread, but can the 05 pipe fit on an 03 header? I hope this hasn't been covered too much.


Not a clue, but what I've seen of the mounts they sure look a lot alike.

Myself, I'd leave the 03 pipe on and just work with the various insert around to get the performance you're looking for.

Sorry to hijack your thread, but can the 05 pipe fit on an 03 header? I hope this hasn't been covered too much.


From what all the aftermarket pipe makers show the 03-05 YZ/WR pipes and silencers all interchange.


Yes. I have a 03 WR 450 with a 05 WR450 muffler with the stock 03 titanium header. They bolted up like they were made for each other. You will need the rear rubber mount which is nothing like the 03 rear mount.


Joe, good work. Thanks for the info...

Thanks for the info. I appreciate the effort on doing this and posting it. Your modified tailpipe looks awesome. Does the coned endcap still fit? :)

I like it. Looks really good. :)

I installed a 2005 exaust on my 04 450 and it totally changes flow compared to stock WR pipe with either the PMB or GYTR insert which I have used both with the stock muffler.

I also have been running a KTM EXC muffler for the last four years to meet sound for races on 250F and 450F and the 05 exaust works much better and tone is lower than the Katoom exaust which was heavier but did the job and now I am so happy that Yammie finally put on Euro style exaust.

Db for KTM exaust was 94db by AMA standards and I'm certain the 05 will be under 96 easy. :)

Hey gang,

Looking to do some more mods to the stock 05 pipe again. Similar to what basicblues is doing (by the way basicblues...keep up the good work), but I'm looking for a donor 05 stock insert. Not really in the mood to cut mine to pieces AGAIN. Anybody willing? I'll pay shipping plus a few bucks? Maybe one of you guys that's got the PMB already :)



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