Help me with my DIO Reed valve

Discussion in '2 Stroke Bicycle Engines & Kits' started by Fletch, Aug 22, 2018.

  1. Fletch

    Fletch New Member

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    Hey how's it going guys. I have some questions for those of you who know about reed valve systems on these bikes, particularly this one I just acquired, which is the DIO cylinder reed valve assembly. I bought this pretty much on an impulse while buying parts to rebuild an old motor bottom end I have laying around. Just playing with it, I have fallen in love with its design. However, I am a little irritated of the fact that I can hardly find any instructions anywhere on these.

    So, now that it is assembled, I'm wondering what I have to do before I can put it on a bike and use it to get results out of it. I have read that in order for a reed valve to work, you need some sort of piston modification to let in more air, such as a window piston. I am thinking about trying to make my own windowed piston. Shall I go for it, or just buy one, or not even bother and just use the piston the way it is? How much of a difference does it really make? Can I just throw it on and go, and notice a difference in ride? Also, the intake hose for the carb on this is HUGE. Even rigging something to make it fit the performance carb I have will still look ridiculous, I think I need a new carb for this. will rigging something to use my much smaller aftermarket carb be sufficient, or will it be too restrictive in flow where I should just get a new carb?
    Anything I'm not thinking of? This is all new territory for me...
     
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  2. Fletch

    Fletch New Member

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    I managed to get my old carb rigged to it which was a nightmare... but anyway I was playing with my dremel today on this piston I had in my toolbox. I see some people do big windows in the side, others do a line straight up from the bottom, I saw one that was a bunch of tiny holes instead of any big one, I wasn't sure what to do. The skirt already had the top of the intake valve area trimmed from before I had a reed valve, so I was just going to use that as a guide and open it straight up from there, but I had this other idea and well here is what I came up with. I think I went too high up with it. Any reason this shouldn't work? What do you guys think?
     

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  3. Tyler6357

    Tyler6357 Well-Known Member

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    Why leave slots like that? I would just open it into one big window.
     
  4. Fletch

    Fletch New Member

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    It just didn't seem structurally safe to me to have that much of the piston just hacked off, this seems stronger. Although I'm no expert, it's just an opinion.
    What do others think?
     
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  5. Tyler6357

    Tyler6357 Well-Known Member

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    Well, here is a picture of one sold by MZMiami. PIC_2794.JPG
     
  6. kaneto

    kaneto New Member

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    All this sharp corners where each slot starts and ends are what is called "stress risers"- they make it easier for cracks to form. At least try to round them off. A little bit of polishing the rough surfaces is also a good practice but not as important as rounding the corners. Also the individual ridges seem too thin in my opinion. If you are concerned about havings a big window try something like that
    https://www.bicycle-engines.com/2-stroke-80cc-high-pin-dual-windowed-piston-kit/
     
  7. doomedgame

    doomedgame Member

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