Topic: Quieting the Motogpwerks exhaust

[KiefRichards]

I've had the Motogpwerks exhaust om my 750k4 for over a year now. Been riding a lot and the noise was getting really old.  It was deafening even with earplugs in, and if stares could kill, man....
It always had the included baffle installed, too.

Decided to build my own baffle.

The baffle tube is 1.25 ID.
The hole in the washer is 0.55in
There are 20 0.2in holes in the baffle.
All the holes combined is equal to a 1" tube, so the exhaust bottles down to around 26mm, basically.


I was worried it would sound wheezy with the baffle, but it sounds great.
Way more quite and subdued, now.
Plus, I was running a little lean in the midrange; the lean condition improved a lot, too. Feels like more torque.

I actually think it could use MORE restriction, like maybe 0.85in bottleneck instead of 1"

With the original baffle, that exhaust was probably sized for a 200hp engine...

[greenjeans]

How does it mount inside the pipe ?    Post some more pics when you have it finished up.   I have one of those pipes as well,
and I feel guilty in the mornings while it's warming up.

[70CB750]

I just have a cheap second hand Mac exhaust, but when the riginal muffler fall apart I run straight pipe for a while.  Same story, neighbors were ready to shoot me.

I made my own muffler with a drilled round plate that the exhaustgas hits first and perforated tube the next restriction.  It helped a lot, the next step would be reverse cone but never got to it.

[flybox1]

i ran one of these for a while in the end of my open kerker.
easy peasy.
http://www.ebay.co.uk/itm/Removable-Baffle-DB-Killer-2-5-63-5mm-for-Straight-Outlet-Exhaust-Muffler-/390682646993

[Muckinfuss]

I take out my hearing aids when riding.  Don't notice any problems with noise or neighbors.