here we go again

Discussion in 'Rack Mounted Engines' started by revelstone, Jul 12, 2008.

  1. revelstone

    revelstone Member

    i'm posting here because the engine is too wide for a frame mount. just wondering if this would work. comments encouraged. :grin: thinking of welding the two sprockets together. the transmission on the side will rotate downward if i remove and replace four bolts. then i just need to figure what size ring to put on the left side. the sprockets are not welded in the picture yet. sort of looking at a GEBE setup arrangement but with chain drive not the belt drive.

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  2. kerf

    kerf Guest

    This thing begs for a rack mount. You'll need those creative juices flowing to fab a mount but it can be done. Use aluminum as much as possible to save weight, plates can be bought from fab shops as cutoffs for a reasonable price.
  3. augidog

    augidog New Member

    i've always been intrigued by that "transmission"...are you sure the available HT wider-cranks wouldn't solve the frame-mount problem?
    Last edited: Jul 12, 2008
  4. Nuttsy

    Nuttsy Member

    I'm gonna be watching this thread very closely. That's the exact engine I was looking at before I settled on the Subaru and rack mount.
    Please keep us posted.
  5. ocscully

    ocscully Member

    Have you run the numbers for your total reduction? Do you know how much reduction is provided by the gearbox? What I'm getting at in a round about way is are you going to have enough reduction with the 16t you show and the available rear wheel sprockets?

    If the gearbox = 3:1 reduction then the 16t to a 56t at the rear wheel only provides a total reduction of 10.5:1 not nearly enough. lets say the target should be in the neighbor hood of 18.75:1 You would need a 100t sprocket to get there.

    If the gearbox = 5:1 reduction then the 16t to a 56t gives you 17.5:1 total reduction closer to the target but still you would need a 60t to get to the target of 18.75:1

    You can find a 60t sprocket from Go-Kart suppliers and then modify it to mount to the wheel of your bike, but a 100t is in the world of custom fabrication.

    An easier solution would be to turn down the teeth of the original sprocket and then reduce the 16t to the smallest cog you can find that will clear the turned down hub?

    Just curious how wide is the engine & gearbox at its widest point?

    Last edited: Jul 12, 2008
  6. revelstone

    revelstone Member

    engine size

    Length (Recoil to end of drive shaft): 12"
    Width (Air filter to Exhaust cover: 11"
    Transmission Mount (Bolt Hole Spacing): 72.5mm

    i know that 72.5 sounds real familiar. aint that like the staton mount friction drive. i know i've heard those numbers before
  7. stude13

    stude13 Active Member

    hi rev; ive got that motor and the trans should be in soon. we can do it! mitch