Breaking the 101 sound barrier on a WB R4

2 replies to this topic
  • John_Lorenz

Posted July 08, 2002 - 04:44 PM


Yaaaaaahoooooooo Yeehaaa whhhoooo yaaaaaaaaaaaaaa

I passed sound check at 99 @ 4500 rpm with a high peak at 6000 = 101.2db

I am stickied :) and good for two years

Yes folks you can too make your White Brothers R4 exahust Sound cheak proof!
How you Say ?
Ego Howd ya Do it?
What is the secret?
Well for a limited time I will offer to TT'rs only, my secret. For a small donation to the I hate Hollister rally fund or happliy nicknamed A real Family experiance or Show your kids how to help a buddy puke up the days beer to make room for more. Or you can simply apply this same effort to your R4 Exhaust or simular.

Here is how I did it
I paid the ranger 100 bucks :D "NOOOOTTTT"

1: I modified the perferated baffle that runs through the R4 with about 30 inverted scoops.

2: I packed it first with a thin mesh of Stainless Steel Wool Grade #1.

3: Then wrap a single FMF Packing tip to tip, do not over lay, this creates a open pocket between the Silencer and the FMF packing.

The loose packing allows the exhaust and noise to perferate to the outer wall (Aluminum) and disipitate inward as well as being scooped by the mods to the baffle.

And a secret ingrediant I will add last.

I will post all the information in the AM, I want to diagram the Mod to the Baffle and the Secret ingrediant.
I was so dang excited I showed the KTM guy I rode with today, how to do a full lock power slide on the TT tracks sweeper,go in way to hot, shoot the berm and crash into a bush :D

Well there was a bigger berm there last time.

Wish I had me vid cam for that one...

[ July 08, 2002: Message edited by: E.G.O.**** ]

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  • Shawn_Mc

Posted July 09, 2002 - 07:24 AM


Ego, which way are your scoops facing? AT the exhaust flow or with?

  • John_Lorenz

Posted July 09, 2002 - 07:33 AM


Facing the exhaust flow to catch the air / noise

We spoke about this theory sometime ago in another post, it worked.

I have them spread out in a slow spiral fashion.

I will be posting the details today.....

[ July 09, 2002: Message edited by: E.G.O.**** ]

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