Kids can be useful to have around...

Discussion in 'Motorized Trikes' started by SimpleSimon, Mar 18, 2009.

  1. SimpleSimon

    SimpleSimon Active Member

    Well, he's not really a kid (26 yrs old), but I live with my youngest son, and he made an off-the-cuff suggestion that made a 120 watt lightbulb go off in my head.

    He was looking at the bike I bought from alesterfiend, and he asked me a simple question:

    "Why don't you just build the front end of a tadpole trike and replace the forks on that bike with it?"

    Well, duh! Why didn't I think of that? So, I'm making a measured drawing of the bike from the fork stem back, and I'll mate that up to a short wheel base tadpole front end (forward boom crank) with provision for it to slide into the fork mount and lock it straight forward by running a pair of braces back to just above the BB. Take the pedals off, mount a freewheel inner chain ring for the forward crank chain to run back to, and the rest of the bike stays exactly as is (sans seat, maybe). Have to lengthen the cables, and I'd like to put disc brakes on the front wheels, but this seems doable to me.

    Can somebody tell me why this won't work? Or even better, give me suggestions as to implementation. Pablo, if you read this, I'd like to know; Will the secondary crank sprocket from your SBP kit work in an application like this?

  2. srdavo

    srdavo Active Member

  3. Should also be easier to control than if the wheels were in back.
  4. SimpleSimon

    SimpleSimon Active Member

    What I have in mind is something similar to what is pictured below. Ends up with a wheelbase 58.5" Long X 28.5" Wide. As I was sketching I realized that there is no need to remove the pedals, or the seat, or the handlbars - I'd just reverese the gooseneck on the fork stem to point back. I end up with a tandem bike, gas engine in the main diamond. Just need the secondary pedal sprocket from SBP, and some Cromoly tubing, a few grade 5 bolts and some parts. Seriously, I can leave the bike completely undamaged - at any point I could convert it back into a two-wheeler quickly.

    The bike is really clean, and solid chrome finished right now - I really don't want to do any cutting or welding on it if it's possible to avoid it. Make a tadpole with 26" rear wheel, already chain driven by a broken in HT engine, and 20" front wheels (which I already have). I'd like to do something kind of funky for a seat - take an old steel rolling office chair that swivels and tilts just a bit, and pull everything off the underside, have a throne with built in arms and back.

    I haven't completed this sketch - the rear triangle needs to be actually drawn, but the lines as shown are correct for the bike as it stands.

    Attached Files:

    Last edited: Mar 18, 2009
  5. SimpleSimon

    SimpleSimon Active Member

    Got to thinking about this idea some more. I really like the looks of curved round tubing - it's just more elegant. It is also much more of a pain to build. So, I did some figuring, and I can cut square tubing at whatever angle I need with a sawzall (which I've got), and make up all of the components for such a build all pre-cut to size/angles needed. Then all I'll need is to get it welded up.

    Welding is a skill I used to have, but all the welding I ever did was with a gas torch. The local community college offers adult education classes pretty reasonably - might just have to take one - might even get some help with assembly that way as well.

    Attached is the idea redrawn as square tubing. I didn't draw in the wheels, pedals, seat or handlebars so as to make the actual frame to be fabricated easier to see.

    Attached Files:

    • TTC2.jpg
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