Undergrad Is a Single Bearing Pedal Possible for Bicycles and Motorcycles?

[christian everett]

I have seen motorcycles and bicycles with only one front fork and I was wondering if the mechanics would be similar enough to make it possible to manufacture a bicycle pedal that has only one bearing where the pedal screws into the crank and no shaft passing through the body of the pedal.
Using conventional materials would it be possible for the assembly to support the forces without failure.
This is mostly a design challenge, weight reduction is not really the goal here.

 

[sophiecentaur]

Possible, perhaps but what would the be the advantage? Such a bearing would need to have a big diameter which would be inconvenient as there is limited space around a pedal crank. What sort of design were you contemplating?
The picture of a half-fork doesn't imply a single bearing; it seems to imply the same arrangement as an conventional pedal / crank; a bearing at each end of a cantilever spindle. What would be the advantage - apart form making a wheel change easier?
I had a folding bike once and, as far as I can remember, those pedals must have had a single bearing, half way out and they could be folded into the vertical plane, when rotated about the middle. Try googling folding bike pedals and you'll see the sort of thing I mean. But I'd bet the bearing was still a double ion a cantilever - just a shorter spindle.

 

[jrmichler]

Those single front forks have two bearings in the headset and two more in the axle.

A single bearing pedal is possible using a four point contact bearing (search the term):

Several manufacturers make them, here is a good source of information on how and where to use them: https://www.kaydonbearings.com/white_papers_7.htm.

A single bearing pedal is possible, but it would be heavy and expensive.