Big hills, longer exhaust tweek

Discussion in 'Performance Mods' started by geebt48cc, Dec 13, 2012.

  1. geebt48cc

    geebt48cc Member

    The bike now will run all day long at mid 20's to lower 30's+. Well, there's a very long hill here in SW VA. that will give any vehicle a work out. I would really be doing good to top hill at around 10-13mph, with also some pedal power?!! Ok, I extended expansion chamber 3" longer on bike. Now, the bike will top this long monster at 21mph, and just continue on at normal posted speeds. (NOTE:It's not a full blown torque pipe like Jag offers plans to build on his site)..................but just adding length to my expansion chamber, really has done wonders!
     

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  2. jaguar

    jaguar Well-Known Member

    It's not clear by the photo exactly what you did to the pipe since it's "clothed".
    Can you make a simple drawing showing before and after and then I can make technical comments on it?
     
  3. geebt48cc

    geebt48cc Member

    Bad drawing

    PUSHED FOR TIME-----------BAD DRAWING, but you can see. I cut SBP's expansion pipe belly, leading into baffle in half. The idea, is to get a 2 to 3 " space..............(Depending on bike).The reason I say total 6", is so you have something to work with when mounting. See, I'm using a rubber boot that I had to experiment best position. Temps there are not high, so I can test for a while. You've just got to be very careful to make sure each end of insert are air tight!~
     

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  4. jaguar

    jaguar Well-Known Member

    OK so you just extended the belly, not the baffle. You can see from my new post exactly what I mean by extending the baffle.
    Having the belly around 2.5" long is the ideal.
     
  5. geebt48cc

    geebt48cc Member

    Jag, I really should of cut even farther back? The end of chamber would be more so the baffle area, right?? I thought that I had the begining of the baffle , or the end of the belly of chamber with the cut I did. That was a SBP's expansion.

    Anyway, then I'm sure that if I didn't cut in right place, that it would even of been stronger if I had, huh?! Seriously though Jag, it really still has a great deal of improvement! Really, I bet that the major change, was with more mids...............See, that hill that I keep on talking about, the bike gain a good 5-8mph faster on top. So.................?
     
  6. jaguar

    jaguar Well-Known Member

    Every change you do to a pipe can improve or worsen the performance. Obviously it needed a longer belly. Now if you weld in a cylinder to replace your accordian then you can cut and weld the baffle as per my instructions. Then you will be amazed once again at the power difference at low revs.
     
  7. geebt48cc

    geebt48cc Member

    Jag, is the accordian really hurting it alot? I'm sure it does break flow a bit............huh?
     
  8. jaguar

    jaguar Well-Known Member

    It may in reality be a good accident. Maybe it diffuses the exhaust wave enough so that the return baffle wave is weaker than it would be. But still it looks weird and will probably develop a leak soon. Just weld your pipe correctly. It will look boss and will work correctly too.
     
  9. geebt48cc

    geebt48cc Member

    Ok, I plan on doing the cylinder soon. With the improvements of performance, you might be right???? True about the leak I'm sure..........
     
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