F8GS aftermarket headers......

Discussion in 'Parallel Universe' started by ebrabaek, Jan 21, 2013.

  1. DoWorkSon

    DoWorkSon Been here awhile

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    I thought of same thing. Remove pipes, cut cat, have shop re-weld straight pipe. Eliminate weight, gain some possible power, and a fraction of the cost
    #21
  2. Motorfiets

    Motorfiets Long timer

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    did the same for mine.... been running it that way since 600 miles

    cut and welded it up all myself though
    #22
  3. ebrabaek

    ebrabaek Long timer

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    Regarding cut and reweld....It is a tempting prospect, and several have done it. A few concerns I have, is that at that spot, or should I say bend, if you have any blow through with the weld, you have a chance for creating a hot spot. If I had a TIG, and knew how to use it, I most likely would do just that. Also having a sudden big chamber empty could mess with the pulses, as rapid expansion, and compression off the gasses on the other side..... That is just speculation, but I know how important good flow is through headers. I am stuck with a mig, and a stick. I dont trust anyone to do a good enough weld.... Second thought, I do have one guy in mind in socal, who I does some Carbon work for...... Hmmmmm..... Now ya got me thinking.....:D
    #23
  4. Gaspare

    Gaspare Almost dirt rider

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    It's hard to believe you haven't the chance to reflash... after all it's the same ECU of BMW cars.
    Here http://f800riders.org/forum/showthread.php/47860-Programmazione-Centralina-F800/page8 there's a friend who reflashed (by himself) via BDM port his 650GS: pls look @ post #383.
    Red is OEM; light blue is modified IAT and blue is remapped.
    Reflashing is surely the best smiles-per-buck option to gain performance: you have the convenience to investigate better to go thru this solution.

    No worries, then: you'll be anyway satisfied. :nod
    #24
  5. ebrabaek

    ebrabaek Long timer

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    I am clueless as of how to reflash the ecu. Well, sort of. But for me that is not an option. I would prefer that over inserting another chip in the middle, but I don't think anyone has done it successfully in this country, and there are a whole lot smarter people here, than I am..... So I will leave that stone unturned.....:D
    #25
  6. toro618

    toro618 Long timer

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    IMHO, you're thinking way too much.

    Just cut it
    [​IMG]

    Gut it
    [​IMG]

    Reweld it and enjoy whatever performance gain it provides.
    #26
  7. Gaspare

    Gaspare Almost dirt rider

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    No doubt there're experts over there... anyway, even for cars, most of workshops are used to send .ori files to specialized engineering studies to manipulate the maps.
    Mainly is matter of experience... and availability of a bench to build up this experience.

    Then, in a month time I'll remap mine, and I'll tell how it is, with all the available details onto procedure...

    Then part II: you're right about the RAM effect... it's not speculation.
    #27
  8. Trout

    Trout Been here awhile

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    I'm running the TWALCOM/QD headers with ADV-spec crash bars & skid plate. Skidplate had to be modified to fit. Search my username for more info.
    #28
  9. jttele

    jttele Been here awhile

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    This is probably a crazy idea, but what's the composition of the material inside the cat? Would there be any way to go in thru the end of the pipe with a borescope and something like a four prong spring loaded wire pickup tool and pluck out a channel thru the cat? I'm guessing it's probably too dense and or rigid for that, but don't know. Possibly a dremel flex shaft tool might also be an option?
    #29
  10. toro618

    toro618 Long timer

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    I think the only way to perform a clean job is open it up. The stuff is way too rigid for any type of a flexible tool.
    #30
  11. ebrabaek

    ebrabaek Long timer

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    I second that opinion....
    #31
  12. ebrabaek

    ebrabaek Long timer

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    Ok... So I have settled on Arrow headers, as it will be hard to beat $399 less 10%. I had an offer to have the stock welded, after I hack the cat, but I am not really sure about the rabid expansion, and compression the gasses goes through in the now hollow chamber. So if any one knows a better price, then please post it, as I will be gathering the headers, and then head up north. I will start a new thread, that will have picture, and video of the dyno runs..... Hoping to start with stock.... then my CF pipe...then headers.... then pv-5 with AT...... Gonna be fun.
    #32
  13. ScienceOfDirt

    ScienceOfDirt U-Boat Rider

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    If you're just trying to get rid of the cat, why not just cut it out, and weld a piece in place?
    #33
  14. ebrabaek

    ebrabaek Long timer

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    I don't have access to a good enough welder, who can do this with out any burn through. And the arrow headers are a few mm larger diameter. Plus... If I don't see the desired results, I can revert back to stock headers.
    #34
  15. Natnewt

    Natnewt Been here awhile

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    Where'd you get the header?
    #35
  16. ebrabaek

    ebrabaek Long timer

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    I have not gotten them yet, but have an email into F800 depot, but after 3 days they have not go9tten back to me. I will let you know where I round them up.
    #36
  17. Imagine1being

    Imagine1being Waiting for the sun...

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    How much louder is the exhaust with the header and aftermarket muffler?
    I don't want to be obnoxiously loud on the street...
    #37
  18. Casejeep

    Casejeep Been here awhile

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    I did a study when i put my Remus headers on, it was only a 2-4db change. the muffler is where the sound really changes.
    #38
  19. Ceri JC

    Ceri JC UK GSer

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    For those gutting their cats... You know Catalytic converters contain rare metals, right? They're worth big money to scrap dealers. They have become so valuable, that in some areas of the UK, police have reported multiple instances of thieves crawling under tall vehicles like 4x4s and cutting the cat out. Don't just chuck it in the bin!
    #39