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The portable small wheel bike

Folks, a bike doesn’t get any smaller than this when bagged, while still being a rather decent (actually; fun) riding bike.

Leaning against a massive black walnut tree

I began thinking about making something like this in 2000. It was drawn up on a big piece of cardboard, and was finished just before the 9-11 World Trade Center attack. My idea was that it could be taken aboard a plane and stored in the overhead compartment. When disassembled, it takes up a space even smaller than the allowable carryon. Your carry-on max size is 22x14x9. This can get to 22x14x7.

After the attack and increased security at airports, I figured there is no way I would be allowed to bring this onboard the plane. I suppose 2 tubes linked together with the chain would make a (really bad) set of numchucks…

It’s made of cromoly aircraft tubing, brass brazed. Tubes are indexed (to resist twisting) and clamped at junctions. Frame angles around 72 degrees. It weighs around 20 pounds. I got the huge chainring from Hostelshoppe. The rear hub is a BMX 110mm Shimano DX unit. The pedals are MKS quick-release.

22x14x7. I had to let some air out of the tires and take it apart rather extensively.  About 15 minutes of work to get it into the box.

To get it all inside the box, I have to disassemble it quite a bit. After taking the frame apart, I took the wheels out, rear brake off, right crank off, removed the seat from the seat post, and moved the left brake lever up. Also, I needed to deflate the tires since they are 15″ diameter inflated. The seat stays fit inside the seat tube, and the top tube fits inside the down tube. It takes 15 minutes to take it apart or put it back together like this.
Leaving the crank and seat on, it would fit the 14x22x9 requirement. Leaving the wheels in place (still bolted to the forks and stays), it would be too big for carryon, but small nonetheless (about 15x23x9) and would take 5 to 8 minutes to assemble.

The gear is 65″. Chainring 63 tooth, freewheel cog 13. I do have a bailout low gear of about 40″, illustrated below:

I can thread the chain on to the smaller inner chainring, and the pulleys to take up the slack.

I will put the chain on the smaller chainring when I have a long hill or mountain pass to climb. It takes a minute and my fingers get dirty, so I only do it if I really need to.

Outfitted for Portland, OR with cedar wood fenders

The longest ride I used this bike on was this 200K brevet. Rides like this awesome/beautiful route on a conventional bike normally take me about 11 or so hours; riding on this bike took perhaps an extra hour. I tend to go faster up most hills and generally slower downhill. With no tall gears, my speed is limited on the downhills and flats. More time to smell the roses and enjoy the scenery!

THE END

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2 thoughts on “The portable small wheel bike

  1. Neat! I came here looking while hunting around for examples of small wheeled, full-size, non-foldable bikes. Basically, I really liked how my Dahon P8 rode, and I want a non-folding commuter bike with the same geometry, but that looks like a beater bike so I can actually lock it up somewhere.

    Like

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