79cc Sportsman Flyer build

Discussion in 'DIY Home Built Motorized Bicycle (non kit)' started by Tom from Rubicon, Jun 23, 2016.

  1. Tom from Rubicon

    Tom from Rubicon New Member

    Joined:
    Apr 4, 2016
    Messages:
    55
    Likes Received:
    0
    The list as I up date it.
    Sportsman Flyer Drop Loop frame (Black).
    Sportsman Flyer Engine Mount System received from Pat Dolan. Seek no more.
    It is the bomb! A better system for mounting a Pred. engine cannot be devised.
    Sportsman Flyer fuel tank with tank graphics and toolbox arrived 10/14/16. You pay the price but you get quality that exceeds my expectations. Well done Pat. The clamp straps have over the top added detail. (These are not conduit clamps.)
    79cc predator engine. Governor removed. Oriented vertical with Pat's system had to drill and tap 1/2 NPT on other side of the engine side case
    PZ19 Mikuni clone + air filter and fuel filter
    On Pat Dolan's recommendation Sunlite springer is the setup to use with a Flyer. Done.
    26" front wheel with Sturmey Archer drum brake.
    26 rear free wheel, Sturmey Archer single gear cassette.
    Continental 26x2 Cream Retro Ride tires.
    Q- matic transmission for 79cc Predator. (Disassembled 6/25/16 to have mounting plate remade of 1/4" 6061 T6 alum. to make it easier for a vertical engine orientation)

    56 tooth rear sprocket and #41 chain for drive
    3 piece sealed bearing crankset, Italian moped cranks, and 25 tooth chain sprocket.
    Wald steel fenders.
    Wald 867 handle bars
    To do the build I have built a bike stand that mounts to the chain stays @ 36" high. just like the one I worked with at a Schwinn Shop in the late 60's and early 70's
    Things may get deleted to make a more cohesive thread.
    Any and all responses, or links to resources that carry this project forward in a spirit that advances our hobby/passion are welcome.
    Tom from Rubicon,WI
     
    #1 Tom from Rubicon, Jun 23, 2016
    Last edited: Oct 15, 2016
  2. Tom from Rubicon

    Tom from Rubicon New Member

    Joined:
    Apr 4, 2016
    Messages:
    55
    Likes Received:
    0
    My first post is to create interest. If anyone can direct me to a maker of a rear facing intake manifold please do.
    Regards,
    Tom from Rubicon,WI
     
  3. MotoMagz

    MotoMagz New Member

    Joined:
    Aug 2, 2010
    Messages:
    1,242
    Likes Received:
    0
    Go to swap shop and contact FfV8 for manifolds.
     
  4. Tom from Rubicon

    Tom from Rubicon New Member

    Joined:
    Apr 4, 2016
    Messages:
    55
    Likes Received:
    0
    FfV8 ? I am not understanding.
     
  5. Tom from Rubicon

    Tom from Rubicon New Member

    Joined:
    Apr 4, 2016
    Messages:
    55
    Likes Received:
    0
    FfV8 ? I am not understanding.
     
  6. MotoMagz

    MotoMagz New Member

    Joined:
    Aug 2, 2010
    Messages:
    1,242
    Likes Received:
    0
    That is his forum name. So he started the thread in the swap shop.
     
  7. Tom from Rubicon

    Tom from Rubicon New Member

    Joined:
    Apr 4, 2016
    Messages:
    55
    Likes Received:
    0
    Thanks for the reply MotoMagz,
    I copy and pasted his forum name in search @ the swap shop forum. Bingo! Posted a massage to him and hoping for a positive response to my inquiry.
    Time will tell.
    Thanks for the help.
     
  8. Tom from Rubicon

    Tom from Rubicon New Member

    Joined:
    Apr 4, 2016
    Messages:
    55
    Likes Received:
    0
    Sorry I haven't any photos here yet, but then again I am dealing with another learning curve. My only other build is a HuaSheng 49cc powered Huffy-Davidson from a Bikeberry kit.
    This last weekend by fits and starts I disassembled an EZ-matic transmission.

    1/4" 6061 T6 plate had been purchased, so I layed out a pattern of the stock mounting plate and the power in put and power out put positions.
    Band sawed the outline, centered and drilled a 5/8" power in put hole.
    Made 4, 5/16-24 transfer screws to transfer the engines hole pattern with the engine vertical and the transmission 90 degrees horizontal. With transfer screws in the block
    Slid the mounting plate onto the transfer screws, and verified 90 degrees. Striking the plate to transfer the hole positions.
    Back out to the shop re-struck the prick marks to help a drill follow center.
    The rest was Duck Soup. Drilled and counter sink’d for flat head screws.
    Back in the house, dropped the plate on over the crankshaft. Screws all fell right in.
    Next is belt sanding to true the saw cuts and transferring the drivetrain components to be mounted up for final assy.
     
  9. Tom from Rubicon

    Tom from Rubicon New Member

    Joined:
    Apr 4, 2016
    Messages:
    55
    Likes Received:
    0
    I did a few PM's with FFV8,
    Resulting in the purchase intake manifold and a flanged exhaust stub that will go on my 79cc Predator.
    Next will be acquiring a 19mm Mikuni carb.
     
  10. Tom from Rubicon

    Tom from Rubicon New Member

    Joined:
    Apr 4, 2016
    Messages:
    55
    Likes Received:
    0
    A package from FFV8 arrived Saturday, that was fast! Any one have a recommendation of which Mikuni carb would work best with a 79cc Predator? Or should I keep the stock carb?
     
  11. FFV8

    FFV8 New Member

    Joined:
    Oct 29, 2013
    Messages:
    552
    Likes Received:
    0
    Any of the PZ19 clones will fit that flange.

    If you search for an XR75 carb on e-bay you will find some under 20 bucks.

    Jetting on those is usually close out of the box. we have used several of them.
     
  12. Tom from Rubicon

    Tom from Rubicon New Member

    Joined:
    Apr 4, 2016
    Messages:
    55
    Likes Received:
    0
    Thanks FFV8,
    Looking foreword to a three day weekend because we do a 4 day 40.
    I appreciate the advice. Thanks again.
    Tom from Rubicon, WI
     
  13. Tom from Rubicon

    Tom from Rubicon New Member

    Joined:
    Apr 4, 2016
    Messages:
    55
    Likes Received:
    0
    Purchased a PZ19 + air filter and fuel filter, $21.00 shipping included. Rainy day here, so the Flyer will get my full attention.
     
  14. Tom from Rubicon

    Tom from Rubicon New Member

    Joined:
    Apr 4, 2016
    Messages:
    55
    Likes Received:
    0
    I got in touch with Pat Dolan of Sportsman Flyer this week and had him invoice me for his excellent 79cc Predator Engine Mount System. I also ordered his tank graphics.
    The engine mount will get this build going. With the engine mounted it will allow me to set up the rest of the drive train and hope I get no surprises.
     
  15. Tom from Rubicon

    Tom from Rubicon New Member

    Joined:
    Apr 4, 2016
    Messages:
    55
    Likes Received:
    0
    Another "What the heck " today. After pulling 6 hrs overtime came home, tapped out the head bearing cups in the Worksman Drop loop frame and intended to install the Monark supplied bearing cups. Nope. Monark bearing cups are 1/32" or .75mm smaller on the OD ( 1.312 VS 1.281 ) than presses into the head. I knew from the start that challenges would arise.
    But this is stupid. It seems my only logical recourse is to machine custom bearing cups that accept Monark bearing and press fit into the Worksman frame head. Producing a tubular shim for the Monark bearing cups even though my machinery could do it. I don't have the steel which would have to be 4140 pre hard to withstand the turning forces 1.312" min. OD 1.281 Max. ID. There are enough challenges in this build.
    I told my wife " This is the year to string Christmas lights on the bike tree.
    Give you one guess how that went over.
    All for now stay busy.
     
  16. Tom from Rubicon

    Tom from Rubicon New Member

    Joined:
    Apr 4, 2016
    Messages:
    55
    Likes Received:
    0
    Here is another thing, Be careful what you want. Do not exceed your capability's unless you have a good machine shop accessible. I own one and a good one at that.
    Having performed work in trade for goods with CostomMotoredBicycles.com I was offered a laced free wheel with disc brake threaded mounting holes which was a return. ( Broken Screw ).
    Today I made a setup in the Bridgeport, the rim supported by blocks on either side of the mill vise. I had the freewheel sprocket against the mill vise jaw so it would not change position. Setup complete, all six holes redrilled and rethreaded
    1/4=28 NF thread which for it's size I think superior to 6mm x 1.
    There is more to this story, but I have been up since 3 AM. I'm running out of gas.
    Tom from Rubicon
     
  17. Springfieldscooter

    Springfieldscooter New Member

    Joined:
    Aug 17, 2011
    Messages:
    297
    Likes Received:
    1
    Keep us posted Tom!
    Photos would be great!
     
  18. Tom from Rubicon

    Tom from Rubicon New Member

    Joined:
    Apr 4, 2016
    Messages:
    55
    Likes Received:
    0
    A package from Sportsman Flyer arrived today. The engine mount system, full head bearing set for the Worksman frame, and a set of tank logos in gold and black.
    Springfield, I apologize for the lack of photos. I have been on this forum for a while and have yet to master photo additions. There is more to share, as making a adapter plate for a free wheel dick brake hole pattern to mount a 56 tooth drive sprocket. Hang in there.
    This build is about to get into gear.
    Tom from Rubicon
     
  19. Tom from Rubicon

    Tom from Rubicon New Member

    Joined:
    Apr 4, 2016
    Messages:
    55
    Likes Received:
    0
    Sent to Pat today.
    Dear Pat,
    Your package arrived Thursday.
    Better than Christmas, I got what I wanted.
    The quality of the Engine Mount System exceeds my expectations.
    Came home from work today and installed the system in my frame in 10 min..
    Only thing I did extra was brake and polish the inside corners of the clamp straps.
    No scratches.
    The top engine mount….first class engineering and execution!
     
  20. Tom from Rubicon

    Tom from Rubicon New Member

    Joined:
    Apr 4, 2016
    Messages:
    55
    Likes Received:
    0
    Mounting the engine is super simple,
    1. Unbolt engine bracket from cradle.
    2. Screw 4, 8mm bolts thru bracket into engine block
    3. Replace engine bracket in cradle and refasten.
    Done.

    DSCN0683.JPG
     
    #20 Tom from Rubicon, Sep 11, 2016
    Last edited: Sep 11, 2016

Share This Page