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Madass 50cc -> Conversion to 125cc?

Discussion in 'Modifications and Projects' at netrider.net.au started by Sage, Dec 13, 2007.

  1. Has anyone ever made the conversion? Is there much difference to the chassis? etc?

    appreciate your thoughts :)
  2. Sage.

    Pretty sure it has been done. Check the net and you will find more info.

  3. This is the net, isn't it?


    Trevor G

    PS Where u gonna git tha 125 injun?

    The 125 isn't all that strong either, which is why 125 owners look for the 150 kit...
  4. havent had much luck with google finding out details..

    whats the 150 kit for the 125 worth? any decent gains?
  5. Sage I bought a lifan outlaw 140cc with oil cooler for my madass. I will be fitting it with heavy duty valve springs and lifted cam (about 7mm), new cdi and lightened oil slinger.

    The 125 cc goes all right up to 90ish Km/h.

    You can pick uo those engines cheap from ebay, they are honda clones. The rands that people recomend more are motovert (very expensive), lifan, jialing and ducar.

    The best place to ask for advice is on the mini bikes forums..

  6. thanks for the info munecito! please let me know how you go.. im curious if its going to be an easy swap or not..

    i was looking at the 125cc Lifan on ebay.. $300 nice and cheap.
  7. I got the outlaw for $240 delivered. It is worth it to use the bidding assistant.

    I will keep you posted. I am going to try to do the swap over Christmas if I can get hold of the cams and springs by then.

  8. looking forward to hearing about it m8
  9. big bump! how did you go munecito?

    i ended up buying a ditech sr50 dropped a 70cc big bore kit in it.. good fun.. tho been 2 years since.. now i want more..

    gonna get a madass 50 and drop a YX160 or Lifan 150 in it..
  10. if you want a madass thats totaly mad
    z160 motor
    v2 head
    oko carb
    and your well on your way
    The z160 has a 60mm piston stock they can go to 65mm reliably (182cc), I have heard of 67mm (193cc)
    In the states some have built these motors to sizes aproaching 250cc
    yx160's have weak cases and lifan 150's although reasonable good for reliability are under powered z155's and z160's are the pick motors for bitumen racing at the moment
  11. hmm.. sabertooth.. i have been doing a lot of reading lately and i havent heard of these z160's..you got any specs on them? how do they differ from the lifan?

    Do they drop straight in to the madass like the lifan and the XY? electrical hookups and all?

    Appreciate the info mate.
  12. The z motors and the yx motors are both clones of the klx110 motor the lifan motors are clones of a crf50 motor. The z motors (155 and 160) and the yx 150 and 160 are interchangeble in the top end componants, the real difference is in the quality of the construction of the gearboxes and cases. The z motors are a better manufactured case. The only specs I know of are the ones on the DHZ site but the ports in the heads are better shaped the stud spacing is better setup to alow big bore kits there are lots of after market parts for these motors. The yx and z motors will fit into any frame that uses the crf50 motor mount setup like the lifans. there is a 5 degree difference in the exhaust port angle between crf and klx style ports so a little masaging of exhaust would be required to make it fit. lifan 140 bore and stroke= 55/59, yx160=57/60. All these z and yx motors use a 60mm piston stock they just alter the stroke to suit. for the full rundown on them check
    yx and gpx motors are esentialy the same both produced by yx, the z motor is produced by ZONGSHEN
    If your wanting to stay with a crf style motor (like the lifan) go for the yx140 or zongshen 140 rather than the lifan as the bore is bigger with a reduced stroke length, yx/z = 56/57 closer to square than the lifan at 55/59 These yx's are very tough mine is big bored to 160cc with a 60mm scut piston and runs 11.8/1 compresion, cam lift increased to 6.9mm from 5.6mm. The oko carbs are well worth the money they really bring any of these motors to life.
  13. fantastic info. i am after bang for buck right now.. so wont bother with aftermarket carbies or different heads.. looks like the z160 is the go :)

    now just to find a cheap 2nd hand madass 50 then i can get going.

    thanks again.
  14. No problems Sage happy to help.
    If it were me doing this project I would do the oko carb (with a uni filter) they make a very big difference to the china motors and are regarded as the best bang for your buck mod you can make. Typical china carbs are pathetc.
    when you do get going with this project post up progress as I am very interested in how it turns out, would be an awsome toy. Be prepared to be a hoon lol
  15. still looking for a 50 to mod.. tho another thing has come to mind..

    isnt the 50cc an auto? and the 125/150/160 all manual? If so then how would you rig up the clutch? and setup the rear brake?

    hmm.. more hurdles it seems.
  16. got one!

    2006 madass 50cc delivered next week. I am on the hunt now for a YX140 is seems! checking out ebay and google though not finding them easy to find.

    apparently i need a 3 phase stator to make any of these engines work with a 50cc.

    will keep you posted.