So, our bike gang has been kicking out another dingus machine. This time we've opted for a standard tall bike design.
In this first picture we can see the pieces that we've hacked appart from a total of three different frames. The idea behind this particular design is pretty simple: get one bike, put another one on top. I've used a mountain bike on the bottom because it has a relatively long wheel base, which adds stability to the ride, a good thing when you are 6 feet up in the air. the top frame is a tiny ladies step-through, which will make the bike relatively easy to mount.
Picture 2 here is a detail of our lovely steering collumn. This was without question the most technically demanding piece of the bike to fabricate, as it has to be 'perfectly' straight so that it would line up with both steering tubes on the stacked double frame.
The particularly ingenious notion with this particular design is that that bottom of this piece was then welded onto an adjustable race for the fork from the bottom bike, allowing the whole piece to be adjusted (or dissasembled) to get an adequite headset adjustment (or overhaul).
With the steering column in place, the parts could be jigged together (picture 4), in preperation for welding. We tacked the frames together where the bottom bracket shell from the top frame meets the top of the down tube (which we slightly cut) from the bottom bike. Then, with left over bits from the rear triangle from the red bike, we cut to shape and then welded in a series of 3 struts, which do the majority of the work of holding the thing together. many other similar tallbike designs lack any sort of serious strut system, meaning that the machine is only welded together in 2 places: i think this one will probably hold together a little better.
Next up we have a picture of the bike after the first test ride. Rides like a dream, feels real safe and sound!!! HAHAHAHA!!! Yeah right. well, much of it felt good, some of it didn't. The frame felt awesome, i doubt it will break. The chain line had some issues, and with no brakes, the bike was what some might call "unsafe." Another note: through a strong tradition of trial and error, others have discovered that a good wheel combination for tallbikes is a 26" wheel in the back, ideally with a coaster brake, and a 24" wheel on the front. This combination makes for best stability. 
Ok, so at this point we had basically put the bike 95% together, and even though it was almost midnight, i knew i had to finish the bike (and this blog entry),and i was taking the responsibility of installing the bicycle componantry and so - blah blah blah - i get a beer and a coffee and fix the chainline and put a brake and a bell on the bike. i have to use a real crappy side pull single pivot brake because it was the only one that would fit. Also, i put it on upside down so that that cable wouldn't get caught in the chain.anyway, it's a pretty sweet bike, i heartily recommend making one yourself.
Dingus Gang!!!
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