66cc Surley Intimidator Mule

Discussion in 'Photos & Bicycle Builds' started by KCvale, Sep 17, 2014.

  1. KCvale

    KCvale Motorized Bicycle Vendor

    This was a challenging custom customer build, he sent me a few boxes of bike parts and a bare frame to make him a mountain mule.



    This is a very small frame to fit an engine in but we got it with some fancy mounting and our own custom intake pipe.

    We had issues with the rear tensioner so we need to test it some but otherwise stick a fork in her ;-}

  2. KCvale

    KCvale Motorized Bicycle Vendor

    After some test rides I changed the drive a bit.

    This mule has so much torque it took out HD Z410 chain twice.
    The engine side has 415 but I can't use it on the right side, it's too wide where the chains cross.

    I did some checking and found some KMC HL710 1/2 link chain.


    I have tried it in the past and hated it but these new ones have a pretty easy to use cotter pin master link which is just a peg as every link is self contained.
    This stuff is double tough and easier to work with these days.


    Look mom! No Tensioners!

    The customer didn't want speed or gears, just a solid reliable mule that would climb a cliff.
    This would make short work of the Grand Canyon mule trail ;-}

    And even without a kick-stand there is always a handy natural parking spot ;-}


    I'm pretty proud of this build.
  3. Bonefish

    Bonefish Member

    That is a nice bike, and you did a good job, but it is too nice of a bike for a china girl.
  4. dirtwarrior

    dirtwarrior Member

    Is it just a single gear bike now?
  5. wheelbender6

    wheelbender6 Well-Known Member

    Looks great. Surly's cost big bucks, for a bicycle.
  6. KCvale

    KCvale Motorized Bicycle Vendor

    Yes, the customer didn't want gears, just single speed.
    I replaced the 7-speed cartridge with a single big 1st gear sprocket and spacers so it lines up perfect with the front sprocket.

    As for the cost of the Surley's yes, they are darn expensive parts but monster strong quality and it will take whatever this guy wants to through at it.
  7. Ollie

    Ollie Member

    Beautiful! I've been dreaming up something similar, but with a 4-stroke engine with centrifugal clutch and a 3-speed hub.
  8. KCvale

    KCvale Motorized Bicycle Vendor

    Thanks Ollie.

    If you want to go full suspension motorcycle tough and use a 4-stroke the MotoPed frame is heavy on the beef.


    It is a direct drive jackshaft to a single speed wheel as well but different, the freewheel doesn't carry motor force, it's just for the pedals to spin.
    And it is designed for a big 4-stroke kick start semi-automatic motorcycle engine.

    I went with this:
    Single cylinder, 4-stroke, 2 valves

    Bore x Stroke: 47mmx49.5mm

    Measurements: 17" x 10 1/4" x 8 1/4"
    Displacement: 86cc
    Compression Ratio: 9.47:1
    Carburettor: racing carburetor
    Ignition: CDI, 12 volt, permanent magnetic stator
    Maximum Power: 6 hp@ 7,500 rpm
    Maximum Torque: 4.25@ 5,500 rpm
    Gears: 4-speed, semi-auto, 4 DOWN.
    Idle: 1,500 RPM
    Final Drive: 14 tooth #420 front sprocket included (we have other sprockets on sale too!!)
    Lubrication: 0.8 liters, 10W/30 4-stroke motorcycle oil, pressure and splash
    Fuel: Unleaded

    Package Contains:

    Buyer will receive 88CC Motor, 22MM Carburetor, Intake manifold, intake gaskets, Shifter, Kick Starter, Wiring Harness, CDI, Spark Plug and Ignition Coil.


    $289.95 delivered and I just got it mounted in last week.


    It's supposed to come out looking somewhat like this.


    Hopefully I can get this done before the Surley customer comes to get his for a 2 bike 'dirt bikes' shot like my 2- bike 'Fat Tire' shots.

    Did I mention I am having fun building all this cool stuff?
  9. Ollie

    Ollie Member

    Nice! I'd love a Motoped, but the 100% import tax to Brazil makes it too expensive. My 4-stroke will most likely be a steel hardtail (not a surly) with big forks and one of the 49cc Huashengs they sell here.