Morini 50cc 2 stroke questions...

Discussion in 'Old's Cool' started by tathambenjamin, Aug 30, 2011.

  1. tathambenjamin

    tathambenjamin Been here awhile

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    I have a new project: Build a 50cc motorized bicycle using an old Morini 2 stroke.

    I bought an ebay engine for $80 only to realize that it didn't come with the flywheel. A new part for this engine (S5E/N) is $124:eek1 . So, I started to scour ebay again.

    Here is my first question:

    Is there interchangeability between flywheels of different shapes and sizes as long as the weight is the same? I found a flywheel from a newer motor (I think mine is pre-'94 without a stator) that appears to fit in every way, except that it is made for the version with the stator.

    I dont know how to determine interchangeability between the two. Ideas, Advice?

    Tried to find pictures,but they are few and far between...
    #1
  2. tathambenjamin

    tathambenjamin Been here awhile

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    #2
  3. OldPete

    OldPete Be aware

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    motorbicycling has a Morini forum. :wink:

    i'm doing a goldeneagle kit on a GT bicycle.
    #3
  4. tathambenjamin

    tathambenjamin Been here awhile

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    I have been looking around that forum, but no one seems to be rebuilding these engines over there, just buying new ones...

    I guess I will have another look and repost there...
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  5. Zecatfish

    Zecatfish XTique Rider

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    Post a picture of the engine.
    I might have a flywheel.
    You will have to get the broken crank piece out of it.
    Came off the kids bike, he was at like 12k rpm when the clutch
    came apart and stopped the engine instantly and the
    flywheel twisted the crank end of the crank off. :eek1

    Its the same engine the LEM and early KTM 50's used.
    #5
  6. tathambenjamin

    tathambenjamin Been here awhile

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    I don't have a picture of the actual engine- it is in my garage and I wont be back home til next monday, but the engine is exactly the same as the engine pictured after the link I posted.

    So, are there supposed to be threads on the end of the crank? Mine looked like there may have been (on the flywheel side) but they were sort of shorn off.

    If you have a flywheel that looks like the one in the linked picture, I would love to buy it off you, so long as it seems salvageable.
    #6
  7. tathambenjamin

    tathambenjamin Been here awhile

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    Zecatfish,

    If you have other parts for the engine- mainly the cdi, flywheel side cover, and any engine mounts (although Im not sure they exist as items separated from the frame) I would be interested.

    Oh, and anyone know of a manual for these things?
    #7
  8. tathambenjamin

    tathambenjamin Been here awhile

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    I see now that there are (obviously) supposed to be many more threads on the crank than I have. Shit. This is turning into a cost prohibitive rebuild...
    #8
  9. tathambenjamin

    tathambenjamin Been here awhile

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    Here's what it should look like...

    [​IMG]
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  10. Zecatfish

    Zecatfish XTique Rider

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    Thats it.
    I'll look for a flywheel.
    There is no CDI box.
    Its is just like a briggs and stratton engine. There is two wires.
    One goes to the kill switch to ground.
    The other is a spark plug wire.

    Now if you really want to get some started, toss that jug in the trash. :evil
    Find the reed valve cylinder, there was two versions of reed valves, one with two leafs and a second with 4 leafs.
    The 4 leaf cylinder makes 12HP and sounds like a model airplain engine, and turns like 14,000 rpm. The 4 leaf also uses a larger carb, I forgot the actual size but I think it was in the 24mm range.

    There use to be a 80cc big bore kit available too. I had one for a bit and the mini would nearly pull the front wheel on take off.

    Then there is a few different clutch configurations, 2 shoe, and 3 shoe, then the Dominator Clutch.

    Most of these kick started forward, my kids never could get the hang of that and I found a side cover that kicked to the rear and made things much easier.


    One last comment, that engine is very weak in that configuration, 2HP maybe, ATK sold a large wheeled mini in 97 with that engine on it. I got one it was a pitiful thing and wouldn't hardly pull the kids around. Thus the reason for learning about different Morini configurations.
    #10
  11. tathambenjamin

    tathambenjamin Been here awhile

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    I have seen the reed valve cylinder, but I am trying to put the engine on a bicycle. I think more than 3-5hp might be overkill.

    If you have a flywheel I would be happy to buy it off you. Sorry I didnt see this earlier- thought I was subscribed to my own thread, but I guess I wasnt...:D
    #11