Homemade baffles for my Griso. Opinions wanted.

actwin · by **actwin** » Sun Feb 05, 2012 12:56 pm

I machined from aluminum billet a db killer for a Mistral slip-on for my 11' Griso. I wasn't happy with the sound from the modified one that I got with the used Mistral so I figured why not make one. What I have is a conical shape 1" at the small end with a 7degree taper and overall length of 4" on the outside. The inside is .875 at the small end and is stepped up from there with 24, .250 dia holes allowing the gasses to flow through. I milled the holes at a 30 degree angle to the taper thinking it will flow better. I was able to try it on a 10 mile ride with mixed results. It needs a little more sound and it may not run as strong from a seat of the pants feel. I'm going to do some more to it, such as open the holes up that are closer to the big end and see what happens. I'm looking for opinions here from all. Thanks,Scott

draidt · by **draidt** » Sun Feb 05, 2012 2:33 pm

Now you had to know this was coming

Bill Hagan · by **Bill Hagan** » Sun Feb 05, 2012 6:13 pm

A wav or midi or other sound file would be good, too.

Rafael · by **Rafael** » Sun Feb 05, 2012 8:03 pm

Can't remember the title of the thread but one fella either took the end cap off or drilled a much larger hole in his Mistgral db killer. Try drilling the small end with a progressively larger hole. The increase flow straight through may help draw more exhaust though the side holes.

Not worthless if you can draw a picture in your mind

.

actwin · by **actwin** » Mon Feb 06, 2012 3:01 pm

Yea I expected the need pics reply. I took it out for a ride today after opening up 4 of the holes by .100 each, it now sounds more to my liking. I don't want it too loud, more of a deep tone which I think I now have. See,I had Ducati's for about 15 years and I LOVE the way they sound so I'm kinda looking for that I guess. I know Mr. Roper says these 8v motors need resistance in the exhaust so I'm trying to make sure there is some there seeing as how the cat is gone with the Mistral. The idea of drilling a hole in the small end just may create more flow from the side holes, now you have me thinking. Thanks for the input, Scott.

Goodvibes · by **Goodvibes** » Tue Feb 07, 2012 12:23 pm

PM member 'apexl' here as he had a Mistral in the classifieds that he had a modified dB killer.

actwin · by **actwin** » Tue Feb 07, 2012 2:02 pm

He's the one I got the Mistral from. Too loud for me with his mods which has led me to this point. The weather here is supposed to be crap for the next week so I won't be able to do any "testing". I need me a dyno!

actwin · by **actwin** » Sun Feb 26, 2012 11:02 am

After adding a .200 hole to the bottom and opening up four of the upper most holes to .300 I took it out for a 50 mile spin. Too loud with more popping and it seems to have lost some of the deep tone. I plugged the bottom hole and will take it out when the roads clear of salt.

Ad B · by **Ad B** » Sat Mar 10, 2012 7:22 am

Hi,

sorry, I waited so long for a reaction.
I have a Mistral High Rise Carbon on my Griso 1200.
I liked the looks from spot on, but it's not the best you can buy...
The standard db killer, killed more than only db's...

On my G12 it killed also several horses...
On the dyna it "only" reached 91.2 HP. A bit less as with standard exhaust.

With open BMC airfilter and adjusted mapping we came towards 100 HP at the back wheel.
With the db killer installed.
Without db killer... The result flew up to a very nice 112 Hp at the back wheel. :mrgreen: