how to lengthen steerer tube on a bicycle

Discussion in 'Motorized Bicycle Welding, Fabrication and Paintin' started by paul, Feb 16, 2013.

  1. paul

    paul Active Member

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    have you ever cut a steerer tube to short? found a great fork for a great price but the steer tube was to short? well i have a bike with a very long neck and no one makes a steer tube that long. i ordered a fork for a great price i was told would work however and when i got it in it the steerer tube was about 3/4 inches short. it is a 1 1/8 standard steerer tube which most bicycles use except bmx bikes. i found out the inside diameter is only 1" which you can find one inch pipe anywhere. i cut the steer tube in half and inserted a piece of one inch pipe and and had it welded to the proper length. i have read all over the net on how to extend them however i think it was just one of them things that was to simple and no one figured out yet or i just couldn't find where. here is a picture of how it was done. made my motorized bicycle that more comfortable to ride. very happy
    [​IMG]
     
  2. Bikeguy Joe

    Bikeguy Joe Godfather of Motorized Bicycles

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    Simple is good. Sometime, people try too hard to "think outside the box...

    Picture of the bike with the new fork?
     
  3. paul

    paul Active Member

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    gonna get pictures next week after i paint the fork to match bike. kinda strange looking now but it sure is smooth
     
  4. curtisfox

    curtisfox Well-Known Member

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    Yep i have done it a couple of times. What i did was use another bike fork and cut the fork tube off it and welded it together with a sleve like yours. Left a 1/8" gap for weld but i cross drilled mine were the sleve is and roseset welded the hole shut. Did the same to shroten a girls bike fork,cut a section out and welded it back togther..............Curt

    PS one should put the bottom bearing rase on it first before welding.
     
  5. paul

    paul Active Member

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    ya it works great curtis. nice thing is that the weld you will never see. i had all but given up on putting shocks on my trek pure electric bicycle
     
  6. LabRat

    LabRat New Member

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    Hay thanks for the PS, just that I find the thread 4 days to late. Had to grind out a good weld now I dont trust the weld. So I started over. Following Paul's leed with the sleve. Thanks Paul, did not think to do that the first time either.
     
  7. biknut

    biknut Active Member

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    Thanks Paul, that's good information. Now if I could just learn how to weld.
     
  8. curtisfox

    curtisfox Well-Known Member

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    Welcome: another thing one should know in the bottom of the frok the is a second tube (renforcement) so the cut should be made midway otherwise the sleve ( one should measuer that first) will not fit good.

    If you ever bend one or seen one bent,they bend just above the inner tube or just above the bottom bearing. If you incorperate the sleve down to the inter tube you will have a much stronger fork.

    All i ever used was another piece of fork tube and split it length wise about 18"and squeze it together and slip it inside for a sleve. 7/8" drill bit cleans the inside if needed,and a 3/4" drill bit will clean the renforsment tube if needed.
     
  9. bairdco

    bairdco a guy who makes cool bikes

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    i just did the same thing yesterday...:)

    i had an old fork from the 30's i wanted to use on a bike, but the steer tube was really short, like 4".

    i chopped up another fork from the junk pile, and welded in an inner sleeve, then put an outer sleeve over that. luckily, i figured out the bearing race had to go on first, as the outer sleeve is just small enough to allow the bearing to clear.

    i double sleeved it because i'm making a really fast bike, and the last thing i want is a broken fork at 50+...
     
  10. curtisfox

    curtisfox Well-Known Member

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    7/8" cold roll fits in them nice and tight if you realy want to stiffen them, also you can use the cold roll to streighten them helps keep it from flatening the tube if you put it in a press..............Curt
     
  11. paul

    paul Active Member

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    lol thats why i took it to a welder. i dont weld either
     
  12. Maxvision

    Maxvision New Member

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    I heard the other day that girls bikes usually have a longer fork tube...c'mon guys, get your mind out of the gutter.

    I have yet to check it out for myself though.
     
  13. curtisfox

    curtisfox Well-Known Member

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    Yep a inch longer and thats the reasion for shortening some of the forks to fit boys frame. And a lot of the ten speeds have longer head tubes
     

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