This stupid thing might be useful if you could adjust the contact surface with the road by changing the angle of the… not-wheels. Like if it could go from pinpoint contact for low rolling resistance (ignoring all the other resistance) to several square feet of tread on the ground for gliding across sand.
Do you want the ultimate tracked experience? Do you want the bicycle equivalent of a mechanical keyboard? Do you like all things tanks? Well, we have the vehicle for you!
I’ve seen an ebike rear wheel replacement that is literally just treads for riding in the snow. I think I’ll just stick with thick tires but it’s still a neat idea.
If you made a bike with a vertical head tube or negative head tube angle, it would not be stable at all. Gyroscope effects are minor in the mechanics of bicycles.
There’s a few geometric parameters that influence straight line tracking. Try holding a bike by the head tube and move it very slowly forward. Gyroscopic effects are negligible at such speeds. Yet, you should notice that if you lean the bike left, the front wheel turns left and vice versa. This is due to the geometry of how the front tire pivots. Since the front wheel turns in the direction that the frame leans, as the bike rolls forward, the centerline of the tire contact patches moves in the direction of the lean restoring the frame to vertical. The reason it is more stable and smooth at high speeds is that the contact point of the front tire moves faster with speed. That makes for smaller deviations from vertical.
A big part of learning to ride a bike is actually learning to countersteer before turns. Suppose you want to turn right. If you start the turn by turning your handlebars to the right, the wheelbase will move to the right and the frame will lean left. Without a quick correction, the rider will topple over the left of the bike. New riders have to train their brains to instead initially turn a little to the left to establish a rightward lean before they can start the turn. Then at the end of the turn, the rider oversteers to get the wheels back under their center of mass before pointing the wheel straight again. This can be easily seen if you ride on a sandy gravel. Make a few turns then look at the track that the tires make.
All this is to say that the biggest factor in stability is that a lean naturally turns the front wheel toward the direction of lean. Traveling forward moves the tires back under the rider restoring a vertical alignment.
All of what you say is true, and that is a fantastic link you shared, but I don't think it really demonstrates that bicycle geometry factors are more important than the gyroscopic effects with regards to stability.
While certainly not scientific, a "ride" on rollers shows this gyroscopic effect quite well. Especially if you clip in... After reading your link, I now would like to try a 90° headset angle! I think.
It looks like a Bike Party kind of bike. Bike parties are events where the city’s bike community can come together. At least out here, they publish the path for that night’s ride, and then the bicyclists will basically take the lane with a kind of parade of weird bikes lit up with LED lights, playing music, and socializing. In several cities around me, it’s a year round monthly event, and homeowners along the route will frequently come out to see the bikes and wave to the riders. This is where you’ll see people pulling out their pennyfarthings and other weird bikes. I could definitely see this used for that kind of thing.
There’s a square wheel bike that I think is similar in terms of the use cases.
Gotta give the dudes credit for a really nicely made video. And I wonder how many hours were in welding and screwing this tracks together.
They clearly dido this for fun/video content, so I’m not mad, but they shoulda added some chain guides (like engine timing chains have), or at least filled the steel tubing with foam maybe.
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