What are your thoughts

Discussion in 'Motorized Bicycle Welding, Fabrication and Paintin' started by placidscene, Dec 30, 2013.

  1. placidscene

    placidscene New Member

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    I dont know welding, but I know a welder that I think will do stuff for cheap for me because I hire him to do fence work for me from time to time.

    I have an old road bike with a steel frame from the 70's.
    I would like to lower my center of gravity on it a bit. I took a profile pic of the bike and drew in yellow lines what I would like to do to the frame.

    What do ya'll think. Along with this, I would also get rid of that stem mounted shifter, and lower the handle bars all the way down. I think this will give me a much more stream line and lower center of gravity while still maintaining my 27" wheel size.
    I travel mostly very smooth roads, in case you want to make comment on my skinny tires! lol
     

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  2. maniac57

    maniac57 Old, Fat, and still faster than you

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    Looks workable to me. One thing I will suggest is you be very careful to keep things straight and true when modding the frame as bent bikes tend to break and wear in strange ways.
    Be SURE your guy knows what he is doing before you trust him with your life at 30mph.
    I've been welding over 30 years and I approach bike frame fabrication with respect. There's not much room for error in a bike frame since there is so little structure.
     
  3. mapbike

    mapbike Active Member

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    Very doable and if he cuts things in correct order it will be a very simple mod proccess, I have an older bike I plan to do the same thing to.

    A 4 1/2" grinder with a 1/16" cut off wheel, a torch capable of brazing with brass rod or torch welding with mild steel rod such as a wire clothes hanger or an inexpensive wire welder will all work nicely to do that simple mod on that bike, all the cutting can easily be done will grinder and cutoff wheel, I'd have him add some extra small braces to the areas that were cut, moved and rewelded just for extra insurance, it's important that the down tubes that run from seat tube down to rear dropouts are welded good and strong when they're re attached, you wouldn't want those breaking loose....... a piece of plate welded acrooss them and then a small gusset from that plate welded to seat tube is how I would want it, that would make the frame stronger in that area than it is now and pretty much bullet proof.

    Map
    .wee.
     
  4. 2door

    2door Moderator
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    The bottom line here is the skill of your proposed welder. Mending fence posts and making good structually sound welds on a bicycle frame are two very different things.
    I'd want some examples of his work on thinner material than steel posts.
    What kind of equipment does he use? Stick? MIG? (with shielding gas or flux core?) TIG?
    Do some checking. A structural failure of a frame could get you hurt.

    Tom
     
  5. placidscene

    placidscene New Member

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    He is a good welder. I hire him for fence, but he does a lot of other custom welding as well.

    I like the idea of adding gussets though, Thanks!
     
  6. tim turbo

    tim turbo Member

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    Shift, good beer!
     
  7. placidscene

    placidscene New Member

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    Yes, Yes it is!
     

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