Very Successful Lifan 125cc swap into 1981 Honda C70 Passport

Discussion in 'Battle Scooters' started by DRconvertible, Dec 16, 2015.

  1. DRconvertible

    DRconvertible Lurking in SoCal

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    Tell me more about this muffler. I looked at a lot I might be able to modify to use on a little Honda and very few looked workable. What's this from, and what did you have to do to make it work?
    #61
  2. YamaGeek

    YamaGeek Skeletor sparklemuffin.

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    I worked at a scooter shop that we refitted non restrictive exhausts on some of the Adlys and SYM Euro-Fighter 50 cc bikes we sold, I acquired a couple of those mufflers from the shop when they closed. The stock ones having integrated catalytic converters. So this is a custom rewelding of the SYM EF50 stock muffler. I don't want to recommend it because it hangs a little too low, and it's quite heavy. I also had to holesaw out the exhaust tip so it breathed better.

    It's quiet and it does a fair job of cleaning up the exhaust fumes. I was posting that I had adapted a 125 engine and carburetor back in 2012 on a old Honda Cub with the snorkle aircleaner. These intake tubes are crucial as they tune the intake and improve the power, top RPM, and torque. Just like the old intake runner did in the old 50 cc pushrod Hondas and OHC 70 cc Passports. For the same reason why adding pod, foam aircleaners buggers with the performance of a lot of bigger, multi cylinder bikes, intake tuning.
    #62
  3. AGAUBERG

    AGAUBERG Adventurer

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    I would be interested in knowing what pegs you used. I also have the Lifan 125, but mine is wider than the stock Honda motor, and the stock foot pegs are both not wide enough and don't have the same bolt pattern to be attached to the new Lifan motor. What did you use?
    #63
  4. YamaGeek

    YamaGeek Skeletor sparklemuffin.

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    Same pegs that came on the C102, I'm running a JumperPro 125 engine, not a Lifan and they fit fine, just used longer bolts and some washers underneath so the pegs clear the engine case sides better for servicing.
    #64
  5. Aaron707

    Aaron707 n00b

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    DRconvertible, Can you tell me what float height setting you used for the carb? I am putting together a similar passport using the same parts and am not sure what way to adjust to the float to make up for the angle of the intake. I found in the manual for the ATC125M it states a stock setting of 10.7mm. Any insight would be appreciated!
    Thanks
    #65
  6. DRconvertible

    DRconvertible Lurking in SoCal

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    10.7mm? That's pretty precise. I would think somewhere along the lines of 11mm would get you in the ballpark. I'm old school, though. I adjust the float to level horizontally with the base of the carb body and then alter it slightly to retain even with the carb body when the carb sits at its final angle. Start with level when mounted and feel how it runs. The bike will either like it or it won't. It'll feel lean on top if it's too low and burble at idle if it's too high.

    Nice RE in your avatar. Yours? I've got a 2015 burgundy chrome C5.
    #66
  7. zvhorn

    zvhorn n00b

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    DrConvertible, I'm really hoping you are still active on this site as I just got a 1980 C70 and have quickly realized I want to do EXACTLY what you've done to yours in this thread. Problem is I am a complete beginner when it comes to wiring. Mechanical I can handle. I'm thinking of tackling this over the winter as a project to work on. My hope is I can reach out to you when the time comes to wire this thing in. I get how the new wires work with CDI and all, but I get confused as to how you attached the new sub harness to the existing stock wiring harness to keep the lights all working??? Like I said, forgive me, I'm a wiring idiot...
    #67
  8. DRconvertible

    DRconvertible Lurking in SoCal

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    PM me with any specific questions. I'm still around. It's been a couple years since I did this build but can remember some of it and the rest is out there to find.
    #68
  9. CrustyCrusaders

    CrustyCrusaders Adventurer

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    Have you come across any mufflers that will work and look closer to the C70 stock muffler?
    #69
  10. aspr

    aspr Not fast, just stupid.

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    How has the long term reliability on the lifan been? Picking up two passports Saturday
    #70
  11. Screamin69

    Screamin69 n00b

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    Thank you guys for the detail on that c70 build. I'm currently restoring my C70 passport and I'm stuck between the 125 lifan or the 100cc kit . Do you have any advice on the 100cc kit?
    #71
  12. DRconvertible

    DRconvertible Lurking in SoCal

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    I'm a fan of the Lifan motor. The quality is really good and they can be made to run really well with the proper carb and jetting. The 100cc kit is likely just a big bore that will increase the power on the stock Honda 70cc but will also increase vibration and decrease reliability.

    Go with the Lifan. The semi-auto 125cc motor is the perfect setup for the C70.
    #72
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  13. Screamin69

    Screamin69 n00b

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    Will it fit the stock air box on a 82?
    #73
  14. DRconvertible

    DRconvertible Lurking in SoCal

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    Yes. It will require a 90 degree hose to mate the carb and airbox but the stock airbox can be retained and is the better way to go.
    #74
  15. Screamin69

    Screamin69 n00b

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    Got it . Lifan it is.
    #75
  16. DRconvertible

    DRconvertible Lurking in SoCal

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    Correction to the post above. The 1982 airbox is different than the early ones. I can't be certain the clone carb will line up with the stock airbox. There'll be "a" way to make it work.
    #76
  17. Ruacoon

    Ruacoon n00b

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    Just joined after finding this thread a while ago, have a 6v 1979 c50 and a 12v lifan semi-auto 110. Not running yet but I think it's all coming together.

    Thanks so much, the info and the pictures have been invaluable, top stuff.
    #77
  18. +venture

    +venture Been here awhile Supporter

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    Nearly done rehabbing a 1980 C70 that was given to me by a buddy 20 years ago.
    Am I crazy in wanting to take it on a serious road trip? I'm on eastern long island so it'd be a ferry to CT and then...?
    My other bikes go much faster, but there is something about this one that makes any ride an adventure.
    #78
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  19. wanna bECO

    wanna bECO Long timer

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    I have put more than 25k on a passport, just riding around town. It is easily one of the most beautiful machines in the world. It is also more comfortable than a new one if you are on the larger side with the long seat. If they had a banana seat on the new one, I'd say get one and tour the world. I am sure DMC will push his to its limit. I'd say do a couple of day trips on the passport and see how you feel on her.
    #79
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  20. +venture

    +venture Been here awhile Supporter

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    Just swapped out the points and condenser and it runs much better.
    When it warms up I’m gonna do just that. The open road at 35-40 max. It’s weird that that appeals to me.
    #80