Whats Up Wit The Pipes

Discussion in 'Sportster Models' started by tattooedjesusfreak, Apr 14, 2008.

  1. Im looking at pic's of sportys and i see mine has a pipe that joins the two and most others dont have that pipe . does it make a diff? is it cuz mine is just stock with slipons or what ? i like the look of not having it but do i need it realy? and does anyone have a Le Pera seat ? im looking at there Mavrick touring seat . and was wondering how it held up
  2. well do you think i should stick with the stock pipes with just the slipons ? im going with the forcewinder i think . i like the look , i will do my eng. mods this winter os im sure ill have more ? about that stuff in due time but for now im just addresing the air on it . id like it to run like a Busa lol . my avg cruzzing speed is 75 to 80 , dont know why but i find my self at that speed in everything i drive or ride . but at that speed there feels like there should be another gear lol how do sportys stand up to this kind of ridding ? i dont do burnouts and hot rod stuff like that . i just like to cruze at a lil bit faster then 65 will the 3000 rpm cruzing take a toll on it ? ive seen on diff post about how sportys are a lil slower than the cruzers , is this so ? am i being to hard on ride? i dont want to ware her out . but i do like to rideum hard and put them away wet sum times lol
  3. scottaudio

    scottaudio Member

    The crossover is running between the header pipes on later XL's and is hidden behind the lower pipes (earlier XL's have the crossover right below the air cleaner in plain site!). If you replace your mufflers, you'll see the pipe!

    The crossover pipe also helps with noise abatement. HD has to meet certain noise emission requirements for some localities that have sound level restrictions. Since the cylinders fire at different times, if you send the exhaust gas and noise through two mufflers instead of one, you have cut down the "loud" factor as each cylinder is "double muffled."

    It also helps with engine scavenging of the cylinders, in that when one cylinder is firing, the other is charging and the exhaust valve is usually still open during the "filling" process to allow the air to "flow through" providing a better charge in the cylinder. When the other cylinder fires, the force of the exhaust helps to "shove" the fresh gas back into the other cylinder through the slightly open exhaust valve and ensures a more efficient charge and use of fuel.

    This process is actually helped along by not only gas pressure in the exhaust, but also by sound waves in the exhaust. This characteristic is actually more prevalent in 2 stroke engines than in 4 stroke, but depending upon what you are looking for (low end torque or more high end horsepower), it can come in to play when selecting replacement headers or exhaust.

    I went with the HD SEII slip-ons and the SE air cleaner. After re-jetting, according to the book I should have an additional 9 HP over stock. I can believe it. My 2006 XL1200C sure runs a lot smoother and the original slight backfiring is gone. I do intend to put it on the dyno when I take it in for the 5000 mile service next month, if anything just to satisfy my curiousity.

    There are a lot of good exhaust systems out there, and it really comes down to effective research AFTER you have sat down and seriously decided what you expect when you are finished: A touring bike, or a 1/4 mile dragster!

    I ride with a group of HD owners from my office, and they all have bigger cruising bikes. On the road or in town, I can out accelerate any of them with my XL1200C. And I do like the performance and handling!

    Good luck!