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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    Yes. If you closely at the pictures you'll see extended brake arms both front and rear. I've replaced front and rear brake shoes with EBC 303G grooved brake pads and feel that they are working as well as drums this size are going to work. The brakes on these bikes, when fresh, fitted and adjusted correctly, are better than people give them credit for. I think that some people ride an underbone Honda with old, hard brake shoes, less than perfect adjustment, hubs that aren't centered, and old tires, and claim they are poor.

    I have more concerns about the suspension. I have installed better, taller rear shocks and plan on adapting an anti-rise link and hub from an earlier model, and new front shocks, to improve the front end. I feel it's okay to 55 mph or so. Faster than that and major modifications would be needed.

    The point isn't to blast away at top speed all of the time, though. Getting to 45 mph with traffic was the goal and it does that well. In Southern California it's almost impossible to go at freeway speeds when you're not on the freeway. We have one stretch of road locally with a 60 mph speed limit and that happened to be the road we were on for five minutes of our ride.
    #21
  2. chazbird

    chazbird Long timer

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    Good on idea on on the extended arms, especially for the front. Where did you source those? I use OEM shoe/pads, they are just so-so...thanks for the EBC part series. The work and documentation you did is top flight, very impressive. I've ridden a Lifan 125 cc with a manual...(like you I'd prefer the semi automatic). The conversion does transform the bike but the one I rode seemed less sorted than yours. Where I ride I don't need to get up to boulevard speeds very quickly so I plan on keeping mine stock, maybe, since its an '81,just to see how long it'll last. PS: by chance are you an ex "9" driver?
    #22
  3. DRconvertible

    DRconvertible Lurking in SoCal

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    The extended brake arms are sourced from Japan. I see them pop up on Ebay every now and then. I actually bought these for another project but wanted to try them on this bike. They're pretty effective. I can tell a difference but it isn't as big a difference as fresh shoes and a good adjustment. I've still got the part numbers around. I'll post those later if you'd like.

    Don't know. What's a "9"?
    #23
  4. DRconvertible

    DRconvertible Lurking in SoCal

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    What's a 9? Dumbass. No, I'm a single engine land only pilot. I was one of those kids that grew up in part in a small Wisconsin town. I regularly watched North Central Airlines CV580s take off and land from the fence and then later worked my way into the hangar areas and talked to the pilots. In the 70s many of the pilots were WW2 vets still in the prime of their lives. They would spend time talking with me and motivated me to pursue a license later.

    Seeing Herman the Duck on the tail of any North Central aircraft has always given me good memories, hence DC-9.
    #24
  5. chazbird

    chazbird Long timer

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    Thanks. The 9 is the photo above your avatar.
    Edit update. The 580's were very cool. They went on to Republic, and then got the sack when Northwest took over.
    #25
  6. DRconvertible

    DRconvertible Lurking in SoCal

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    Yeah. I still dig the 580s. I can remember hearing them on approach and that would signal me to get on my bicycle and ride down to the airport. I'd listen to those Allison's high-idling on taxi into the ramp area and think it was the coolest sound in the world -- until I heard a Ducati.

    In the 70s I would regularly fly to and from Central Wisconsin Airport to Milwaukee or Chicago on 580s to catch a flight to spend time with my Dad in Southern California. Often, the flight took place near the deck under thunderstorms. I've seen 580 wings flexing like a duck flapping its wings and in constant turbulence and they just growled along.

    I got to fly Republic a few times as well. I think the DC-9 in my avatar is actually a Republic aircraft.
    #26
  7. CA_Strom

    CA_Strom Cunning Linguist Supporter

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    Well this thread motivated me to swap the tired and unreliable 89cc pushrod motor from my 1965 ct200 to a new Lifan 125cc semi auto. Today was tear down day....

    [​IMG]

    A couple hours later and it was down to the bare frame:
    [​IMG]

    Cart full of parts:
    [​IMG]

    Got the old coil out that hasn't seen the light of day since 1964!
    [​IMG]

    I'll be getting my motor from PCC motor in Ontario since I live real close to them. From DrATV I'll source a footage adapter and a 6v swap kit that includes new harness, 12v to 6v rectifier, new non-powered key switch and some other do dads. Time to go shopping!
    #27
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  8. nashopolis

    nashopolis Been here awhile

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    Nice write up.

    Maybe I missed it but what did you do to make the footpegs work?
    #28
  9. DRconvertible

    DRconvertible Lurking in SoCal

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    I used this footpeg setup: http://dratv.com/thwoforliwil.html -- but the stock peg setup can be widened by welding in a section of tubing to the right of the mounting studs to push the right side out a couple inches.

    CA Strom -- looking good. I'm currently looking for a CT200 frame as a platform to a build for a 140 motor I have -- something more trail oriented.
    #29
  10. CA_Strom

    CA_Strom Cunning Linguist Supporter

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    Well I had a successful trip to the will-call desk at PCC Motor in Ontario CA. I returned with a nice shiny new Lifan 125cc semi-auto Motor kit, carb, straight intake, intake adapter, and a $15 pit bike exhaust header that I think I can make work with my old CT200 pipe/spark arrestor. All this for $400! Looking forward to some shop time to get this all sorted out! I've got another order coming from the good DrATV that will sort out the 6v-12v wiring and footpegs.
    #30
  11. wanna bECO

    wanna bECO Long timer

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    As someone who has put around 30k miles on passports, all in Phoenix, I am surprised I am seeing this thread for the first time.

    I am a large guy and I have no problem with the top speed of the pass port. My daily driver will do 46 on a long flat road. (greenway between cave creak and 7th st. for example) The reality of the bike is... you are usually doing 42... really 39 to 42 most the time. The issue with the pass port is the ramp up to the normal flow of traffic. This is where the danger lies. And I have many other bikes too. The passport is bad because in I don't like to be the first person at the light... I wanna be doing about 30 when I hit the intersection. The other thing I like to do on a bike.... when going though an intersection, I like to be in the curb lane, and have a car at my 11 o'clock as I go though an intersection. Left turns here are scary as hell. I have been hit, on a passport, by someone turning left in front of me... of course, they just didn't see me. The car at my 11 o'clock position is what I use to block me as I go though... if an idiot turns left, let them hit the car. On my larger bikes it's no problem to keep myself safe and accelerate to keep my "blocker" there, but on the passport... not so much.


    I have been intrigued with upgrading. The thing is, I have to literally kill the OEM motor and without direct neglect, that isn't possible.

    Your upgrade is the best that I have seen. You keep the original intake, and I have not seen anyone else do that. If I ever do this, I will follow your example to the "T".

    Tell me, what shocks did you use on the rear? Did you have to change anything on the bike to make them fit?
    #31
  12. DRconvertible

    DRconvertible Lurking in SoCal

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    The rear shocks are HD 280mm shocks designed for a Honda Z50. This auction will go away with time, but here is a link to the same set currently on Ebay: http://www.ebay.com/itm/Honda-Z50-Y...m4aeefc5360:m:mdu3qmGqleeyj0r7ZMNbjZw&vxp=mtr . They are significantly stronger than the worn out original shocks and will raise the rear suspension about 1/2 - 3/4". They went on without any modification. The stock shocks are about 260mm.

    CA Strom -- how is your swap coming?
    #32
  13. CA_Strom

    CA_Strom Cunning Linguist Supporter

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    Moving along nicely. I got the motor mounted up after grinding a few clearance areas from the frame. I added a perimeter frame pit bike intake and I was able to get the carb in the stock forward facing positition with the original air box. I added a 2-1 Petcock to deal with the single line 22mm carb.

    I was hoping to fire it up today, but ran into a couple issues that stalled me:

    1. Tank was a bit rusty, so I did a 24 hour vinegar soak. Then found out at some point there was a poorly done tank liner done to part of the tank. Need to get that all sorted out and dry.

    2. I bought the foot peg adapter from Dr ATV, but for the life of me can't get it to work. My ct200 pegs are too tight on the brake lever side. I need to figure this out or find another peg that will work with this wider motor.

    3. I had bought a cheap pit bike header pipe that I was hoping to hook up to my stock CT exhaust. No go on that so now I need to get a pit bike exhaust that I can make work.

    Hope to have it running soon. I also bought an updated key switch, wiring harness, and 6v-12v regulator from the Dr., so after I get it running I'll tackle the electrics. Stay tuned!

    Photobucket is fubar'ed right now, but pics later!

    Here's a picture of the mounted Lifan 125 with the carb that came with the kit:

    [​IMG]
    #33
  14. CA_Strom

    CA_Strom Cunning Linguist Supporter

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    Quick update. I got the Lifan 125cc all wired up for initial start. No lighting circuit yet, just wanted basic hook ups to get it running. Nice! Motor fired up on the second kick and purrs like a kitten! Tried to ride it down the driveway with no footpegs (still need to sort those out), but quickly noticed I have a chain issue. My 1965 ct200 runs a 428 chain and the 125cc Lifan is shipped with a 14 tooth 420 chain sprocket. This resulted in some issues with the chain not seating on the sprocket.

    I ran down to PCC Motor in Ontario to pick up a 420 chain, but that didn't work either. My rear sprocket won't work with a 420 chain. So, I'll have to wait until Monday to go back to PCC and pick up a 14 tooth 428 chain sprocket and I should be in business.

    I'm very happy with the ct110 exhaust I picked up. With a couple of spacers from Dr ATV, it bolts right up to the Lifan and even retains the exhaust hangar on the rear shock mount. I'll get some pictures up when it's all buttoned up. Thanks for all the advice on the thread.
    #34
  15. DRconvertible

    DRconvertible Lurking in SoCal

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    I put the leg guard back in place and fab'd a crossbrace on the underside. My daughter has been riding the Passport regularly and it is about time for the third oil change for the new Lifan. It continues to ride and run well.

    [​IMG]

    [​IMG]

    [​IMG]
    #35
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  16. Culcune

    Culcune Been here awhile

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    Great job on the engine swap. These crate (or ex-pit bike) engines are cheap alternatives to restoring these old bikes. Obviously, yours was running fine, but all over Craigslist, there are CT-70's, CT-90's going fairly cheaply with only needing an engine swap.
    #36
  17. chazbird

    chazbird Long timer

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    Nice work and nice bikes. My Passport photo's, if I had any, would be NSFW...and not in a good way.
    #37
  18. INTERNETRACECAR

    INTERNETRACECAR livin' la vida lifan

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    Now that I've finally committed and ordered a motor (and shortly the remaining few bits from Dr. ATV, because doing an ATC125m swap into a CT90 at the same time wasn't enough), I was curious about the origins of the footpegs, as they look like the perfect fit for the task. I have the stock ones and a set of early CT90 ones to mess around with and I'm certainly not above doing some surgery to make them fit, but those look like a much cleaner alternative, and I'd much rather hunt down a set of no-fuss ones that will fit once and not have to be an issue after.
    #38
  19. fullmetalscooter

    fullmetalscooter Let me take this duck off

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    Any real diff between the frames of ct110 , passports etc ?
    #39
  20. CA_Strom

    CA_Strom Cunning Linguist Supporter

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    I finally got the OEM pegs from my 1965 ct200 to work yesterday using the $18 adapter plate Dr ATV sells. It took a bit of finesse and I had to enlarge a few holes, but works perfectly. Pics coming once I get it all buttoned up.
    #40