Sidewinder - Front wheel drive - Rear steering trike

Discussion in 'Motorized Trikes' started by srdavo, Feb 15, 2010.

  1. srdavo

    srdavo Active Member

  2. professor

    professor Active Member

    I use an electric pallet jack that you ride on.
    As long as I have the steering wheel LEADING the direction I am traveling, all is well. Going the other way- with the steering done in the back- it can get real squirly FAST. Just like that trike, it has a short wheelbase and 3 wheels (sort of). Only goes about 10 mph though.
  3. SimpleSimon

    SimpleSimon Active Member

    I like that - A LOT!

    Really nice design. I can see a couple of options to power that little puppy.
  4. srdavo

    srdavo Active Member

    yeah, I can see where it could get a little crazy, but I'm an old forklift operator, from way back..... & I could get used to it. See how he cut those low speed square corners? And the spinning would be a hoot!!

    Don't get me wrong....I couldn't justify buying one, but I might build one???
  5. srdavo

    srdavo Active Member

    I'm thinking a Staton friction kit on the rear wheel....?
  6. SimpleSimon

    SimpleSimon Active Member

    That's doable, but poises some real issues in very tight cornering situations. I think I'd go with a behind the seat 35cc 4 banger feeding a powered chain loop forward to a freewheel capable crank chain ring, a la SBP's jackshaft, and let the power feed thru the gearing system/differential. The Samagaga differential is very nice, but that is one expensive bit of gear, if you can get one.

    I'd go with an internal geared hub as a mid-drive, and do the "poor man's differential" that I've explained before.

    Whatever you do, remember two things - reverse Ackerman is absolutely critical in a rear-steer trike, and a good deal of camber on the front wheels/half axles would be a REALLY good idea. For that reason I've been looking at twistable link belt as a final drive possibility, as is used in many industrial applications - you could go with up to a 15 degree negative camber, athough that is very high.

    For myself, the biggest issue is being able to do differential brake steering - I haven't worked out a way to make that doable with my left hook, although I have a couple of ideas.
  7. Leisesturm

    Leisesturm New Member

    Sidewinder themselves now offer power assist on two of their models. They put a hub motor in the back wheel. My inner test pilot says that would try to 'fold' the bike on the steering axis but I never argue with reality. Seeing is believing. Staton sell a couple of differentials that don't cost as much as the name brand stuff. I like the double freewheel idea though and would use it if tight for cash, or space. Do you really mean 'Ackerman'? Just wondering. I also think you could simplify things a lot and not worry about camber. None of the rear steer designs in production have any. There must be 3 or 4 inches of trail in that Sidewinder rear end though.

  8. SimpleSimon

    SimpleSimon Active Member

    I've been contemplating on this thing a good bit, and I have a design mostly worked out. As I see it, the 20" rear (steering) wheel would be powered by, say, a Tanaka 32cc engine via cogged belt, a la GEBE's system. The engine is mounted co-planar with the rear wheel, above it, on a mounting yoke that pivots with the wheel.

    The front two wheels would be powered via pedal chain back to a multi-speed internally geared hub, then forward again to a pair of independent "half-axle" jackshafts, with fixed geometry final chain loops to the actual stub axles.

    There is a method to the apparent madness, actually - I want the seat as low as I can reasonably get it, and with this design the seat is at 11 1/8" off the ground. A variable length crank boom allows for different height riders. This way, with 26" front wheels, the CoG is well below axle height, and trailing the main axle height by about 16".

    With a 30" wheelbase width and a wheelbase length of just 34", this thing will turn on a dime and give you nine cents change - hopefully without flipping over.

    I'll have a sketch or three to post soon.
  9. SimpleSimon

    SimpleSimon Active Member

    Well, here it is - a first pass design study for a pedal/gas powered hybrid rear-steer tadpole trike, fully recumbent.

    As shown in the attached pictures, the yellow translucency represents the crank to the multi-geared internal hub drive, the red translucencies represent the drive loops to the jackhafts, and the green translucencies represent the final drive loops from the jackshafts to the stub axles.

    I have not drawn in the seat except as a basic wire frame to indicate placement, nor have I drawn in the steering control input/transfer system, for which I am of the opinion that aircraft control cables would be best.

    As drawn, I envision a GEBE style drive system, but since the rear wheel is only a 20" one, GEBE does not make one. Which is fine, as cutting the bottom off a 5 gallon plastic paint bucket, and wrapping a cogged belt turned teeth outward around it and affixing it will suffice (or get a proper toothed manufactured 5 spoke sprocket wheel designed for toothed belt drives). Engine mounts to the rear pointing rack, which swings with the wheel.

    Attached Files: