New Twist On Banana Pipe

Discussion in 'Motorized Bicycle Welding, Fabrication and Paintin' started by massdrive, Nov 5, 2013.

  1. massdrive

    massdrive New Member

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    I sat on a stool in my garage next to my bike for a spell each day for 2 weeks trying to figure how to mount my banana expansion chamber. I didn't like the standard down sweep between the peddles. I wanted an up sweep exhaust keeping the expansion chamber as close to the header as possible. I also wanted a nice clean mount with out drilling holes in the frame or using clamps and brackets too. This is what I came up with...
     

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    #1 massdrive, Nov 5, 2013
    Last edited: Nov 5, 2013
  2. massdrive

    massdrive New Member

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    opps posted twice how do I delete?
     
  3. maniac57

    maniac57 Old, Fat, and still faster than you

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    Not seeing anything mass...
     
  4. xseler

    xseler Well-Known Member

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    There's 2 of the same threads. No issues for me........but the other one has the pictures.

    Looks like a great job!! I need to buy a welder....
     
  5. massdrive

    massdrive New Member

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    I mistakenly posted the thread twice. The other post has the pics. How do I delete?
     
  6. maniac57

    maniac57 Old, Fat, and still faster than you

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    Ask a mod. They will get it eventually anyway, but asking is nice.
     
  7. massdrive

    massdrive New Member

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    Thanks maniac57, Good tip about the using down sweep handle bars for curved exhaust tube around frame. Wish I'd thought of that could have saved a brand new exhaust pipe for another build...
     
  8. massdrive

    massdrive New Member

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    After setting the pipe exactly the way I wanted it with what ever I could use to shim, block and hold it in place I tacked it together. After tacking it securely I removed it and finished welding it. I'm an experienced welder and was confident that it would fit after welding so I went ahead and painted it with 2000 degree heat paint and installed it after it dried. As I said before I didn't want to drill any holes in the frame or have some crazy looking brackets on it so while the paint was drying I fabricated a doughnut clamp with a drilled and tapped mounting pad from aluminum pipe and clamped it to the rear down tube, and screwed the banana pipe to it. I'm very satisfied with the final outcome. Bonus; it oils my chain for me... lol I'm going to add a 70 to 80 degree curved tail pipe to the end to blow the exhaust away from the bike...
     

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  9. GearNut

    GearNut Active Member

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    Your pipe came out looking good, massdrive!
    I like the high mount look. It gives it more of a dirt bike look than a low slung street bike look.
    I used a motorcycle crash bar and buck horn style 10 speed bicycle handlebars to make this exhaust: http://motorbicycling.com/showthread.php?t=30761
    I was going for the low slung moped look. I still have the bike but never ride it. It needs new forks.
     
  10. buba

    buba Member

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    nice job

    but do not burn your inner thigh

    that will certainly be painful!!!
     
  11. dodge dude94

    dodge dude94 New Member

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    Wanna make me one? :D


    Looks awesome! Great work.
     
  12. mapbike

    mapbike Active Member

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    Nice job, I used an old set of 10 speed handlebars to make my header pipe for the last expansion exhaust I made up for one of my bikes, diameter of the pipe is a bit smaller than I would really prefer but it seems to be working out ok so far.

    first pic was before I had brazed it together, then brazed and then welds ground down and painted with VHT High Heat exhaust paint.

    Yeah I know.............this is a monster pipe, but the performance gains are excellent with this pipe, I have the SBP pipe on another pipe and it is good pipe also but didn't add nearly as much mid range gain as this big old honking brute of a pipe did so I decided to make it work on this bike best I could without using a super long header pipe, it's a bit cramped on here but not enough to bother me since ride with my left foot forward anyway.

    again, nice fab work on the header pipe and that is a very clean mounting job you did with the custom seat tube clamp/mount.... great work massdrive!

    Map reddd
     

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  13. rock out

    rock out New Member

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    Nice a Skyhawk frame! Sweet looking pipe too! Quick question did your frame come with the rubber cushion for the front mount?
     
  14. maniac57

    maniac57 Old, Fat, and still faster than you

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    What kind of bike you got?
    Might be willing if I can find your frame here to use as a template...
     
  15. massdrive

    massdrive New Member

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    Yes getting burned is a concern. I put about 10miles on it so fare and no burns. Although my pant leg sometimes heats up and lets me know that a burn is imminent so I move my leg. I'm working on a simple heat shield like the dirt bike from the 70's had, or maybe I'll just wrap it with heat tape?
     
  16. massdrive

    massdrive New Member

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    Thank you. I was 1 key stroke away from buying a wiggle pipe, but wound up with a banana... Maybe I use a wiggle on the next build.
     
  17. massdrive

    massdrive New Member

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    I'm using a gt2a-s frame available online from many sources. Shop around prices vary widely. I bought mine for buck eightytwo including shipping.
     
  18. massdrive

    massdrive New Member

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    I bought the banana kit form Sick Bikes. It came with the header and one piece of curved pipe, the banana, and lots of mounting hardware and flex tubes non of which I used. As fare as making one for you I would need the bike. Unless you live in or near Vegas it would be cost prohibitive to ship your bike back and forth, but ya if you supply the bike and the banana kit I'll make one for you for a nominal fee.
     
  19. massdrive

    massdrive New Member

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    I think I sometimes get off track and respond to posts on related subjects. lol Oh well it is what it is...
     
  20. massdrive

    massdrive New Member

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    A heat shield is in the works or maybe I'll just wrap it..
     

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