Gutted stock exhaust??

Discussion in 'Crazy-Awesome almost Dakar racers (950/990cc)' started by KEELAYMONSTER, Nov 5, 2012.

  1. KEELAYMONSTER

    KEELAYMONSTER BRRAAAAPPP!!!

    Joined:
    Feb 11, 2012
    Oddometer:
    232
    Location:
    Pleasanton, CA
    Has anyone gutted the stock cans and tried them out? Im not talking just de-cat them, I mean gut everything. Im curious how they sound. My thoughts are they might sound like crap.:huh Im just looking for a cheap way to lighten them and make them run a little cooler. If they dont sound to horrible ill probably gut mine.

    I have already checked the stock cans "guts" on the HOW. Looks easy enough to do.:evil
    #1
  2. KEELAYMONSTER

    KEELAYMONSTER BRRAAAAPPP!!!

    Joined:
    Feb 11, 2012
    Oddometer:
    232
    Location:
    Pleasanton, CA
    I suppose I should state these are off a 950 A. Could be helpful to know :deal
    #2
  3. DeepInIt

    DeepInIt Long timer

    Joined:
    May 19, 2006
    Oddometer:
    1,370
    Location:
    Cordoba, Argentina
    Define gut. If you truly gut them, it will sound like an obnoxious Harley and run like crap until you rejet it.
    #3
  4. tunp

    tunp Been here awhile

    Joined:
    Apr 28, 2011
    Oddometer:
    307
    Location:
    almost SE PA
    yes it can be done. i run a truly gutted and reworked can.

    But it takes some work. I cut both end caps right behind weld, then you need to hole saw out the exhaust outlet (1 1/2" hole) is what i used. On the back side of can you must cut all the way thru which will cut thru the cat pipe also
    After that you can slide the whole baffle assembly out.
    I then reweld rear cap back on, welded an 1 3/4 dia pipe to the end cap, then used a 1 1/2 stainless preforated baffle thru can packed with baffle material i suggest stainless steel wool as the normal packing did not last long.
    for the end cap i cut a pc off the interal baffle and welded to the inside of can so it projects enough to rivet the end cap on for repacking.
    It will work and sounds good but it is loud, i ended up fitting an FMF spark arrestor on the end cap to reduce noise level.
    #4
  5. idahoskiguy

    idahoskiguy Long timer

    Joined:
    Jun 22, 2005
    Oddometer:
    1,147
    Really?...............Your bike won't run any better and actually worse until it is rejetted. Glad I have left the stock exhaust unmolested, seems like a waste of time and money on these bikes for NO GAIN.
    #5
  6. KEELAYMONSTER

    KEELAYMONSTER BRRAAAAPPP!!!

    Joined:
    Feb 11, 2012
    Oddometer:
    232
    Location:
    Pleasanton, CA
    I am aware of the necessary re jet. Did the setup you made weigh significantly less than original or is it relatively the same. Also do the cans run cooler?
    #6
  7. WARRIORPRINCEJJ

    WARRIORPRINCEJJ Crazy, on a ship of fools...

    Joined:
    Jun 29, 2009
    Oddometer:
    17,280
    Location:
    Leanna Decker's panties
    The cats, not the baffling, is what makes 'em run hot...


    .
    #7
  8. KEELAYMONSTER

    KEELAYMONSTER BRRAAAAPPP!!!

    Joined:
    Feb 11, 2012
    Oddometer:
    232
    Location:
    Pleasanton, CA
    aaahhh. good to know. maybe just de cat them then.
    #8
  9. sailah

    sailah Lampin' it

    Joined:
    Aug 12, 2005
    Oddometer:
    6,138
    Location:
    Turning expensive metal into scrap
    If you want some nice cheap light pipes, buy some carbon cans from a ducati and have a welder make a quick flange to the stock mid pipe. Takes a lot less time than gutting the stockers and lighter too.
    #9
  10. Sporting Wood

    Sporting Wood I

    Joined:
    Oct 18, 2011
    Oddometer:
    902
    Location:
    Horneytown, NC
    The search button can be your friend. Theres several old threads about this, many with pictures and directions.
    #10
  11. tunp

    tunp Been here awhile

    Joined:
    Apr 28, 2011
    Oddometer:
    307
    Location:
    almost SE PA
    so wieght savings was part of my goal when i did this and yes it easy drops 10-15 lbs between the two cans. My other goal was to go to a 2 into 1 setup and use the other can as a storage box which now holds my elec pump, a front and rear tube, first aid, spare plug, zip tyes and jb weld.
    So was it some work, yes, does my bike look stock w/ addtioanl storage and more rumble, yes. are the cans much cooler, yes. Did it affect performance and or mileage, no.
    I looked at it this way if it all worked it cost me a few bucks for material and some time which i was willing to put into it. If it did'nt work, well then i buy after market cans which i was going to do. And now i dont have to.
    #11
  12. KEELAYMONSTER

    KEELAYMONSTER BRRAAAAPPP!!!

    Joined:
    Feb 11, 2012
    Oddometer:
    232
    Location:
    Pleasanton, CA
    My thinking exactly. If i can spend some of my time to save some money Im all for it.

    The used cans was actually my next route if this doesnt work. I have access to a welder and a bunch of other fun tools at my work.

    Also the search button sucks. Every time I try and use it it shows me a bunch of totally irrelevant stuff if anything at all. I did try manually looking through the OC posts though and didnt see anything. I have also checked out the HOW and saw whats all inside the stock cans.

    Thanks for the input everyone. Ill post whatever I end up doing. Working on cutting my stock windshield down a bit today.:evil
    #12
  13. K2m

    K2m ....58....

    Joined:
    Feb 27, 2005
    Oddometer:
    2,238
    Location:
    Sydney Australia
    Sorry WP Not True ;-) Remove the cats as I did in 2005 and nothing changes heat wise.

    1/ The exhaust run through the middle of the bike makes the middle of the bike bloody hot

    2/ The standard muffler has 1mm of insulation under the outer skin to protect it from internal heat. This does 5/fifths of fuck all to help cool the outer skin down.

    3/ An aftermarket muffler is a perforated tube with 2 1/2 inches of insulation wrapped around it under the outer skin. with the exception of a little conduction of heat at either end where inner joins outer the outer it is well insulated.

    4/ The whole standard muffler is designed to function as a cat.

    There is only one way to get rid of the heat, get rid of the exhaust.

    You can build your own like I did or the GPR is a very attractive proposition.

    If you do not like the heat............

    You need to move the exhaust system out into the flowing air along with your voltage RR
    #13
  14. KEELAYMONSTER

    KEELAYMONSTER BRRAAAAPPP!!!

    Joined:
    Feb 11, 2012
    Oddometer:
    232
    Location:
    Pleasanton, CA
    Allright.

    So I have been running a 2-1 setup with a de-cat stock muffler for a while now. It's just as hot as before and really made no difference in sound or performance.

    My next route is to use the outer of the stock can and replace the innards with a perf core and lots of packing. Im sure it will be loud, require a re-jet, and still be relatively heavy but it should be much cooler. Im have a stock muffler off an 08 CRF450 that i am going to rob the innards from. I'll report when I finish it...
    #14
  15. Zander

    Zander Been here awhile

    Joined:
    Mar 21, 2008
    Oddometer:
    194
    Location:
    Montreal
    Hi K2M,

    Where do you relocate your voltage regulator to get it into clean air and keep it protected ?
    #15
  16. Head2Wind

    Head2Wind MotorcycleMayhem

    Joined:
    Mar 13, 2006
    Oddometer:
    2,661
    Location:
    NorthWet Washington
    zzzzzzzzaaaaaaaaaaapppp...... dead thread revived :D

    As you start to cut the OEM muffler apart, you will discover that it is possible to gut and reconfigure. You also will discover that it can be a bit of a PITA to work with because the outer shell is not single walled so welding it all back together can be challenging at times.

    I believe that the OEM mufflers 'run hot' because the exhaust spends a bunch of time in the muffler traveling between the three chambers before it finally exits. The cat can be a contributing factor, however I do not believe it really makes all that much difference in surface temps one way or the other.
    #16
  17. Zuber

    Zuber Zoob

    Joined:
    Sep 28, 2004
    Oddometer:
    2,613
    Location:
    Main Street, Shedd, Oregon
    I've completely gutted a stock muffler, but did not install it. When you pull out the double wall with the soft packing, the muffler shell will ring like a bell. These would make a good high pitched wind chime. I suspect it will ring the same way when used on the exhaust too.
    #17
    Gryphus1 likes this.
  18. tunp

    tunp Been here awhile

    Joined:
    Apr 28, 2011
    Oddometer:
    307
    Location:
    almost SE PA
    My experiance with this will disagree. Once you get your preferated tube and packing material in place its now a muffler not a wind chime
    #18
  19. K2m

    K2m ....58....

    Joined:
    Feb 27, 2005
    Oddometer:
    2,238
    Location:
    Sydney Australia
    The reason Zuber did not install it is because even gutted it's a heavy heap of shit and a waste of time................ just buy some mufflers :lol3

    I have just had a complete year away from bikes, and ADV.... a sabbatical :freaky
    #19
  20. K2m

    K2m ....58....

    Joined:
    Feb 27, 2005
    Oddometer:
    2,238
    Location:
    Sydney Australia

    I guess the simple way would be........... anywhere the wires reach. I have changed my bike so much that it would no longer be relevant to a normal LC8.

    [​IMG]
    #20