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Lifan 125 build

Discussion in 'Chinese Mini's' started by T.J.Brearley, Jun 12, 2018.

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  1. Jun 12, 2018 #1

    T.J.Brearley

    T.J.Brearley

    T.J.Brearley

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    So I'm currently in the teardown and design stage of the process of building a fairly non-stock Lifan. Im planning on porting, shaving the head, considering on getting a shorter rod and making a shorter cylinder, race cam from a different china motor, better valve srings, bigger valves and maybe bore the cylinder and put a 56mm in it instead of a 54mm.
    1. how do i finish splitting the cases, I've cracked the seal but cant get it the rest of the way off
    2. where would you recommend getting descent gaskets from
    3. what cam would i use
    4. what valve springs should i use
    5. should i upgrade case bearings
    6. would I be able to use another clutch in it, maybe a five or six plate to handle the power?
    Ive got a relatively small budget and have put this into consideration but i have family that can help with pretty much all of it Im wondering if its possible to create over 11k roughly out of a worked Lifan's because i see alot of 150, 160 and 190 builds but rarely any high-output 125's
     
  2. Jun 13, 2018 #2

    xLOCOx

    xLOCOx

    xLOCOx

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    Have you considered a gpx125, they're currently on sale at dhz for 450 or something, they easily keep up with the 150-160, run an oko on the gpx and you won't look back
    To be honest if you spend all this money on the Lifan you'll most likely surpass the price of a brand new gpx,
    Look in to it! :)
     
  3. Jun 13, 2018 #3

    motodevo

    motodevo

    motodevo

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    +1. You can make more power with a 125 but having a crank mounted clutch , any extra power will cause the clutch to shatter or even exit the cases. That’s why all larger capacity chinese engines have a secondary clutch rather than a crank mounted clutch. TB used to make a big bore kit for the 125, but they stopped once the 140s came out because the 140 was cheaper and 10x more reliable
    If you want to get a bit more out of your lifan 125, just slap a z40 cam and hd springs in it(about $40) and a flat slide 26mm carb and ride it til it blows up.
     
  4. Jun 13, 2018 #4

    T.J.Brearley

    T.J.Brearley

    T.J.Brearley

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    cheers for the response, ive got it torn down to the cases so im going to just rebuild the bottom end to factory spec and paint it. I'll probably just port the head in that case get a new clutch and make a running engine. Would you guys be able to check my other thread about my frames as I have two lifans and was going to build those frames with the lifans but hunt for another engine, probably a 150 or 160.
     
  5. Jun 14, 2018 #5

    T.J.Brearley

    T.J.Brearley

    T.J.Brearley

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    what is the difference between a oko 26 with a power jet v a usual one
     
  6. Jun 14, 2018 #6

    T.J.Brearley

    T.J.Brearley

    T.J.Brearley

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    will the z40 fit because it looks way different to the stock 54mm 125 cam
     
  7. Jun 15, 2018 #7

    motodevo

    motodevo

    motodevo

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    If you have the bigger lifan "race" head. You do need to use the swap the bearings(ie use the original cams bearings), i did it a few years back on a L125.
     
  8. Jun 15, 2018 #8

    T.J.Brearley

    T.J.Brearley

    T.J.Brearley

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    the engine code is 1p54fmi. Can you tell if its a race head or not from that?
     
  9. Jun 22, 2018 #9

    locko90

    locko90

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    Pretty sure thats the type r head lifan 125.

    Can ya post some pics of the build so far mate?
     
  10. Jun 22, 2018 #10

    locko90

    locko90

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    Screenshot_20180623-080108.png
    Yep u have the type r head.

    Question. Why would u want to shorten the stroke? That would give u less torque/power?

    Ive had a few of these engines and there very reliable and have more bottom end tourqe due to the longer stroke and large fly wheel. (Non inner rotor kit)

    It was actualy alot easyer to wheelie my pit bike with a 125 rather then my 155z.
     
  11. Jun 23, 2018 #11

    T.J.Brearley

    T.J.Brearley

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    I was more thinking of boring it to 56mm and then getting a shorter rod to get come more rpm out of the engine
     
  12. Jul 17, 2018 #12

    jonathanpg

    jonathanpg

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    Lifan 125 not good for upgrade, because too many big cc engines come out with cheap price
     
    Last edited: Jul 17, 2018

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