Tuesday, June 26, 2007

Collapsible Tallbike for $10

This bike was built in the early winter and spring months of 2005. I knew that I would be doing some overseas travel that summer so I wanted to take this bike with me and see if it would stand the test. In the past I have taken tallbikes to Poland, Brazil, and New Zealand but never this compact. I feel like I paid my dues and was ready for a more compact tallbike to travel with. Once the bike was planned out and built the first official outing was to ride it to the annual St. Chino Ride that covers about 35-40 miles one way and the only part of the ride I was concerned about was the last hill coming into Stillwater. I had a fear of the bike just coming completely apart on me causing others to crash around me but in the end the welds held strong and it completed its first test and gave me more confidence to bring it overseas three days after Chino.

Step1-3. I welded two couplings on the bottom frame so I could break it down smaller. There is a company out there that manufactures a professional grade coupler for a very steep price (about $500 for one frame) and won’t allow anyone that’s not approved by them to install them. Understandable. This inspired me to find a cheaper way to do this project. I actually found these couplings at Home Depot in the plumbing department for about 2 bucks a piece. Way cheaper than the other guys. I wasn’t sure how they would mesh with the bike frame since the couplings are made of cast iron. So anyway I welded them on and I put the bike through a series of stress tests to see if they would hold up and they did quite nicely. Only thing is that I have to keep the threads greased or else they start to rust. Not a big deal.

Step 4-5. I made a sleeve for the bottom frame so that the steering column would be able to collapse. I used a nut and bolt system but no matter how many of these things I make there always seems to be slight movement in the steering. I hope to develop a better way of doing this so there’s no play whatsoever and would lend itself to quicker assembly and disassembly.

Step 6-9. The deal with the top frame is that I wanted a good strong connection with the bottom frame so the best way I found is to weld a small tube on the bottom of the top frame bottom bracket and then put it into the bottom frame seat tube, then tighten the bolt to secure it while you align the steering column and get ready to bolt the top frame steering sleeve bolts.

Step 10. From here on out it's a pretty basic bike assembly. I start with the bottom bracket then move to the pedals, bars, seat and seat post, and then wheels, derailleur and chain. Whalah! A completely collapsible tallbike.

Here are a few notes:
Bottom Bracket: I used a sealed bottom bracket so I don't have to deal with overhauling it for some time. It will break down one day but it should be good for at least a few years. I picked it up here in Mpls and got a good deal on it for only six or seven bucks. I recommend this so when you get out on the road somewhere you don't have to worry about your bottom bracket seizing up -- good luck overhauling it out in the middle of nowhere.
Handlebars: Obviously, with the small bars the point is to make them as compact as possible so they don't take up a lot of room in the box. It's just that simple.
Wheels: I used 26 x 1 3/8 for the rear wheel and I used a 24 inch for the front but I made sure to use at least one quick release for packing purposes. It just doesn't work with two full length axles so I opted for the front wheel to be quick release cause I don't like the idea of my rear wheel with a small axle taking all the pressure. This is exclusive to the tall bike because of the fulcrum being slightly off balance putting more stress on the rear wheel, yada yada yada, you get the point.
I used a chain and a half and set the derailleur where it is for no particular reason but it just seems to work better this way for me. Others have different ideas.

Packing down:
A friend of mine put this bike box together for me and I went with 25 1/2 X 25 1/2 X 11 to be sure to meet the airline specs of a grand total of 62 inches L+W+H. It was a tough job trimming and grinding parts to fit but in the end it worked and I didn't get charged for any oversized luggage. Sometimes you can get charged up to $75 or more for oversized luggage. I think the packing down pictures speak for themselves. The only thing that comes to mind is that you can take either a small hand pump and pump for hours or you can take an upright shop pump which I ended up doing at the last minute. I was actually surprised it fit but it helped cut down on the assembly process. I just can't stand those little crappy pumps.

Tools you will need:

Chain tool
Channel Locks for tightening the couplings
Crank puller
Mallet for assembly and disassembly -- very handy
Socket Wrench
Crescent Wrench/Spanner
Gerber Tool for tightening steering column nuts & bolts
Always bring extra tubes.

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