# Silent circular motion with resistance

I'm making sort of a desk cycle. What are the ways to make silent circular motion with resistance ? (I don't need to adjust resistance and resistance should be just light.)

If I didn't need resistance, I could use a bearing. Or maybe there are regular bearings that have some specific resistance ? I see there are also magnetic bearings but I had really difficulties to find their prices and those ones that I found costs in hundreds. Are there some cheap ones, ideally ~ 15 or less bucks ? Or do you have an idea how to achieve silent circular motion with resistance ? I was thinking of something like winding/unwinding - continual never ending loop against some weight but that would require changing of the motion from wind to unwind to make it never ending and honestly it seems it isn't very simple to design.

Many thanks

• How are other desk cycles made?
– Wasabi
Commented Nov 8, 2017 at 17:57
• @Wasabi: Noisily.
– SF.
Commented Nov 9, 2017 at 10:01
• @Wasabi : Some use pretty much a bolt to create the resistance but of course it isn't silent at all and also gets quite a hot, some use magnetic bearings.
– B J
Commented Nov 9, 2017 at 19:15

You could try agitating a viscous fluid. Connect your pedal crankshaft to a vertical shaft (via a pair of quiet bevel gears) which has a paddle on the end of it that is surrounded by some thick gloopy fluid like motor oil (or something preferably water soluble).

The viscosity is proportional to the resistance. You could vary the resistance (while pedaling) by moving the paddle up and down so that it descends into the fluid to different depths. Maximum resistance will be when the paddle is fully submerged.

This will be pretty much silent if you choose a good linkage between the shafts.

Imagine a paint stirrer, the principle would be the same.

• Thank you, interesting idea! I can't upvote so at least marked it as the answer.
– B J
Commented Nov 9, 2017 at 19:17

you might turn a generator and either dump the power into a resistor or use it to power something.

Of course silent is a bit of a subjective term.

• Thank you. Well, yes, let's say what would most people consider silent operation.
– B J
Commented Nov 9, 2017 at 19:17