Make a Portable Tallbike!

Most tallbikes are not made to be transported. If you don't have a pickup truck, or maybe a roof rack, it's going to be tricky to take your tallbike anywhere. In my case, I was building a tallbike for a friend who lives about 100 miles away. I saw that there are only a few Tall Bike instructables, and they are very informative and inspirational, but I wanted to show another building method that turned out very well for me. If you have an intermediate level of bike-wrenching experience and can weld okay, this should be no problem.

This is my first instructable, so I hope it is clear, enjoyable, and inspirational! (give me your feedback on anything and I will revise) I re-use the same photo a lot because I don't have the bike in my possession right now to take others. Hopefully it is all clear anyway.

Goals for this tallbike:
-to be sufficiently tall, but can be easily dis-assembled, sort of like a folding bike. for fitting in a trunk or on a trunk mounted rack, or even in a rear passenger compartment if necessary.
-to ride as much like a "regular" bike as possible, specifically steering and pedalling.
-to be Relatively quick and easy to build with a minimum of welding, cutting, and custom fabrication.
-to be as strong and sturdy as any other tallbike building method
-to be disassemble-able with a minimum of tools and time

Ingredients:
-a couple of similar-sized bikes from the trash or wherever. If you're reading this, I assume you probably have a bike pile. I used department store BMX frames because they have nice straight forks (more on that later), thick steel that is easy to weld, and they are pretty to easy to find in the trash.
-a stem with a bolt on plate that holds the handlebars, not the kind of stem with a pinch-bolt.
-a steel seatpost for the bottom frame. This gets welded to the top frame.
-a front hub. find a wheel that is taco'ed beyond repair or has a bunch of broken spokes, or even a broken spoke flange. Make sure it is not too small or big in diameter to clamp into the stem!

Tools:
-standard bike tools like allen wrenches, adjustable crescents, chain breaker, pedal wrench, channel-lock pliers, etc
-hammer probably.
-a couple 4-foot long 2x4 pieces of lumber or other nice flat, straight pieces of lumber
-at least two 4" or 6" c-clamps, speedclamps, or something you can use to clamp to boards together.
-Welder. Whatever you have on hand that wont burn too hot. I used a $89 stick welder from Harbor Freight, some 1/16" rod, running at about 50Amps, plugged into regular AC outlet.
-Your other welding tools: helmet/goggles, gloves, chipping hammer
-Angle grinder, if you need/want to clean up welds.

Step 1 Headtubes

The key to having your tallbike handle like a normal bike is taking time make sure the head tubes (the tube of the bike frame that your front forks go through) of the two bikes are aligned as closely as possible. If they are not on a common center line, your bike will resist steering. You can get away with a little mis-alignment, but the steering will want to straighten itself and every time you turn the handlebars it forces your whole assembly to flex.

This building method eliminates welding in a longer head tube or chopping up forks and welding in a fork steerer extension. It also allows adjustments, dis-assembly, and helps during the rest of the build.

Comments

[grundisimo]

My friend has one 20 feet tall. I'm not lying.

[0087adam]

that doesn't look dangerous at all.

[sprocketscientist]

Thank you for the constructive comment. It's no more dangerous than any other tallbike.

[banterboy]

 Very clear and concise instructions. Could probably lose the back wheel forks on the top bike which would ensure it would take up less space when taken transporting.

[sprocketscientist]

True. However, part of the idea I was going with on this build was that both the top and bottom bikes could be disassembled and turned back into two normal bikes. All that would required on the top frame is to hack off the welded on seat tube.

[cody316]

id like to build one, can somebody please make an instructable on how to get on it though lol, its the first time i ever see something like this, i will put my bicycle trailer hitch and trailer instructable on this week.

[efmca]

nice instructable! I put one together in a couple hours. My kids call it the "crazy bike" and the neighbors look at me funny. I love it! Thanx for the idea.

[cjbikenut]

Nicely handled project and clear well photographed instructable. I tip my hat to you

[cybergod]

WOW ! That looks fun. But to make it MORE portable, maybe consideration could be given to the following idea. I see the front forks of the top bike are attached using a bolt/nut fastener. That means it can be detached as needed. To make it more so, how about instead of welding the bottom seat pole to the top bike frame, could a "tee" bracket similar to that used in scaffolding to attach the two bikes. Don't know if it would work for sure, but a possible way to make it more portable? Thoughts??

[budgetbiker78666]

I don't think that would make it any more portable as it already collapses into the size of two regular bikes which can easily be placed on a bike rack or in the trunk, the bike i have stands at just around 7'6" and it collapses to fit in the trunk of my camry so this being much smaller than that, should have no problem at all.

[cybergod]

Ahhh, my apologies. I didn't think straight. I see now, you can remove the seat post and detach at the forks and it is then seperated. Well done. Must try this one day when I have some spare time.

[Bartboy]

SWEEEET!!!!!

[budgetbiker78666]

Hey great instructable I did the same thing a while back it works great for a while but since the steering column is not straight the weld will break in a few months depending on the use of it, so if you add a brace from the bar you attached to bottom bracket and run it diagonally to the bottom tube, this one has held up for a few years and still riding. Oh and also if you run it straight from the bottom bracket to the rear wheel with a de-railer fixes all chain issues and also gets you some nice gear action. Good luck and GREAT INSTRUCTABLE. -Budget Biker-

[sprocketscientist]

Thanks for the feedback BB. Well, on this bike, the steering column is almost exactly straight. Before I hooked up a brake cable, I was able to do a barspin. That's the whole point of aligning the headtubes and matching the offset of the bottom bike stem and top bike's fork. I suppose the weld might break anyway, but I added a lot of metal there. At least, it's a stouter weld than some of the original welds on the frame! I am keeping my fingers crossed for my soon to be brother-in-law who will be riding it XD