I'm going to build a 2WD rig.

Discussion in 'Hacks' started by larryboy, Aug 8, 2008.

  1. larryboy

    larryboy Chopper Rider

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    Let's brainstorm first...

    This thread was very helpful: 2WD


    Another thought that I've had is this Toyota transfer case that I have sitting here. It's totally bada$$ and would work perfect for a left side car, but I have a right side entry Ural tub and it would look retarded on the left side. Nice idea, it has a divorce front adapter with a double reduction box and an e-brake on the back, they make a flip kit for it, but it's $700:huh .

    Scratch that idea.

    [​IMG]

    I can easily duplicate the Mobec Duo-Drive box.

    [​IMG]


    I'll do the suspension like they do for the Super-Drive.

    [​IMG]

    I think a trip to Pick-N-Pull is in order next to look for donor vehicles for suspension and stuff.

    I'm thinking double A arm hung off the sidecar frame for the bike drive wheel and the same for the sidecar driver...I may get trick and hang the front the same way, but without putting power to it. In all reality I'll probably stick with a leading link front for simplicity.

    I'm thinking of building an all new frame for the sidecar rather than modifiying the existing. This will give me a good sidecar frame to sell that will fit a Ural tub since the mods I'm making will be forever...no turing back.

    I need to come up with a jack shaft drive to get power from the bike over to the sidecar. Time to start stripping parts.

    If anybody has ideas for me, throw them in. I'm all :ear 's.
    #1
  2. RedMenace

    RedMenace Adventure Sidecar

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    If you are going to all that trouble make the new front end hub center and link it to the SC wheel and make that steer too.

    With a driven and steering sidecar wheel you can move it way forward and have a super stable rig with easy steering and no drag or pull at any speed.

    Me, I'd just slap some links on the thing and extend the sc swing arm to reduce the lead by about 5" and call it done-I never finish my complicated projects....:rofl
    #2
  3. larryboy

    larryboy Chopper Rider

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    Yeah, K.I.S.S. or I'll never finish it.:deal


    Hmm, steer the hack too? That might be too much for my little brain to handle.

    I'm going to build it "expandable". Simple to get back on the road, while leaving options for the future..such as reverse, steerable sidecar wheel, lowering/raising, etc.
    #3
  4. larryboy

    larryboy Chopper Rider

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    I'm never very good at these type of threads...I forget too much. :scratch


    Anywhooo, the point of this project is that I have a crashed sidecar rig. I tried to go simple and fast...get some wheels built so I could throw a leading link on it and get back to riding. I can lead a horse to water, but can't make him drink..aka, wheel builders seem to have a hard time actually building wheels. After 2 months of waiting I have given up. If they want to charge me shipping to get my parts back they can keep them. Sooo, the project shifts gears into something more complicated.


    Okay, typing out loud here..

    Jackshaft. Easy enough to build. Say the bike has a 15t countershaft sprocket. I can go to another 15t to get over to the sidecar, another 15t will be on the jackshaft at the SC, from there I run a short stretch of chain to my final drive sprocket, 42t or whatever it is. I can then go back into my own fab'd box like the Duo-Drive using whatever size sprocket I want in the splitter box. Right? Once I'm geared down with the 42t it stays at that RPM, right? Or is my thinking flawed?

    I'm going to throw this pic in here again to clarify for myself.

    [​IMG]


    Yeah, once it hits the final drive ratio you keep that rpm going and split out to the wheels using smaller sprockets to keep the size of the box small.

    Right?

    They're using a viscous coupler at the SC drive axle. I'll probably use a collar type mechanical disconnect like the rock crawlers use for front wheel drive only on the Toyota's.


    The end result I'm hoping for is somewhere between Hog Wildz rig and what I had originally...without spending a small fortune.
    #4
  5. larryboy

    larryboy Chopper Rider

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    Been looking around the 'net at hub center front ends..pretty cool, but would be far too complicated for me right now. Wilbers suspension has a really cool page of customer rigs with their shocks and stuff.

    I'll stick with a leading link front since it's easy for me to build and I have a bunch of parts already that can be used without spending more $$.

    What's the skinny for using a car wheel on the front with a hub that will mount a rotor?

    Think I can go single disc on the front and put the second disc over on the hack wheel using the front brake lever to accuate both? I've got an adjustable proportioning valve that would let me adjust for straight braking.
    #5
  6. bk brkr baker

    bk brkr baker Long timer

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    Hello Larry,

    I did a 4600 mile cross country ride on a FJ 1100 Yamaha with a Sidebike chair package. This is a French made outfit with centerhub front end,13" side and front wheels, 14" rear wheel, car tires all around and sidecar steering too.
    The front brake set up used both Yamaha calipers on a single disc in the front. The sidecar wheel had a brake and that was coupled with the rear on the bike. This was well set up and very stable under hard braking.
    The sidecar wheel steered about half as far as the front. This set was also well thought out and worked great. After I made an adjustment to reduce the toe in I found that you could steer the rig with your foot on the linkage. With a throttle lock this made for a lazy ride ,arms crossed watching the world go by in Texas.
    You may enjoy the site Some Fear .com.
    #6
  7. larryboy

    larryboy Chopper Rider

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    Thanks, baker!! Helpful info, I'll check out the site.

    I'm going to be using front wheel drive car stuff so I'll lock out the steering function on the hack to get me on the road for now, with the option to make it functional later.

    For home engineered I really think I should play it safe and go with a leading link. I can get a little more wheel travel and feel more confident building it.
    #7
  8. zenben

    zenben all roads are one

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    Unless you live somewhere where snowfall requires most people to own a snowmobile, I can't really see a point to 2WD.
    If the design exercise is the whole point, then I can see appeal.
    Proof of concept is rewarding, if not always rational.
    As a senior ME project, this would undoubtedly get a high grade.
    #8
  9. Kyler

    Kyler Confused Hack Nut

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    Dual-sporting is a great use of 2WD. Gravel and mud can benefit from some additional traction. Otherwise I agree. But then, if we all were purely logical, we would all ride the same bike, eh? :lol3
    #9
  10. bk brkr baker

    bk brkr baker Long timer

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    Please, don't try to discourage Larryboy with logic, I want to see this built!:lol3
    #10
  11. RedMenace

    RedMenace Adventure Sidecar

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    Hi Ben!
    I think you might be missing the point.

    TWD is not just for off road and Ural's design approach is niether the only nor the best design possibility for TWD. One huge plus of a modern twd system with a differential is handling: no sidecar drag, straightline acceleration without yaw, reduced tire wear and reduced fatigue.

    I suspect Larryboy is trying to correct some of Yellow Suzi's design flaws. It pulled hard the way I had it set up when we traded bikes. And I understand the front end needs some attention...
    #11
  12. larryboy

    larryboy Chopper Rider

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    The whole thing is that it's a crashed rig at the moment..and like Vernon pointed out, I really don't want to end up where I started. Yes, I could handle it how it was. I love the appeal of the Ural 2wd and treat my machines in much the same way that Mr. Cob does...so I have a need. I've crashed sooo many times on 2 wheels when hitting ice or snow and would like to extend my high country riding season with a 2wd rig.

    There is also the second attraction of possibly getting my wife or daughter to come to Death Valley with me if I took the sidecar and creature comforts that would make the trip more enjoyable for them. I don't trailer anything anywhere. It gets ridden or it stays home...I like the speed and power of the Bandit powerplant or I'd just scrap the whole thing and buy a Ural.

    So that's where I'm coming from.:deal


    Now how about some of you web riders answer some of my questions?

    :beer
    #12
  13. larryboy

    larryboy Chopper Rider

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    I just took the time to look at the some fear dot com site. I now understand how to build a hub center front that is strong enough...makes perfect sense. I love the cantalevered shock mounting..way cool. Too much for me on this project.


    [​IMG]
    #13
  14. zenben

    zenben all roads are one

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    OK, The justification makes sense.
    I have studied the concept before, and settled upon a Subaru diff as the logical choice.
    A long chain driven transfer case is how the Mobec is set up, but it seems simpler to me that a shaft would cross the sidecar at the rear, and chain drive forward to the chair wheel, not unlike the original military R75:

    [​IMG]

    The above hub center design looks like an RDS. One of the more elegant looking solutions. Also available with sidecar steering.
    #14
  15. ag_streak

    ag_streak Tiene Ruta Cuarenta?

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    THAT is about the most ambitious project I have ever seen! Bravo! :freaky
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  16. larryboy

    larryboy Chopper Rider

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    I'm not really thinking full time 2WD, I'm thinking more in the line of the Ural..engagable 2WD.

    I can't think of an easy way to get power from the chain driven motorcycle turned and into the pinion of a differential..much too complicated.

    Simple jackshaft with a Mobec style chain box to split power with an axle disconnect for the sidecar axle shaft.


    This kind is slick looking, but not easy to use. I don't want to be laying in the mud to engage the axle.

    [​IMG]


    I'll be going with some more like this, cable actuated and easy to engage from the seat of the bike.

    [​IMG]


    I know a guy that has experience building these for the rock crawl guys and Trail Tough in Oregon has a smaller one for the Suzuki Samurai that might be more suitable.
    #16
  17. oppozit

    oppozit Banned

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    Chain drive bike with sidecar drive - Norton Big Four. Instead of a differential, look at a viscous coupling. Essentially acts as a differential with an automatic difflock.
    #17
  18. Nixels

    Nixels Face fears - live life

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    :lurk

    If you need some help at Pick&Pull - getting tools or schlepping parts, let me know.

    This looks like a great project. :clap :clap :clap

    Good luck.

    Nicky
    #18
  19. larryboy

    larryboy Chopper Rider

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    Well, after 3 months of back and forth with East Coast Wheel I finally got my parts back from their failed attempt to build me wheels. They totally suck as a vendor..lies,lies and more lies.

    I really wanted my rotors and rear sprocket back...finally I might make some progress.


    Viscous coupler donor vehicles? Subaru I'd imagine. I'll go to the auto recycler this weekend with the camera and look for donor parts.
    #19
  20. larryboy

    larryboy Chopper Rider

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    :lol3 we posted at the same time. Thanks for the offer of help, Nicky. P-N-P is really close and easy for me.
    #20