It can be done, but with a lot of micro- and macro-adjustments. I guess that's what you're saying, but regardless, I agree with you.

The thread is for myths, not facts. :thumb:

What if you ride both road bikes and mountain bikes?

What are you trying to say? Do you think there is gyroscopic effect at 3mph? How about 2mph?

I ride my mountain bike on pavement, how obnoxious is that ?

My experience says if you throw your leg over a skinny tire bike even once you have to be careful, you could magically erase any good dirt mojo you may have accumulated over your entire life. Bicycling magazine concurs.
On a serious note: I did a lot of riding on both road and dirt from the birth of clunkers until a few years ago. Now it's a forty-mile drive one way to get to the trails, but those trails are soooo sweet that I'm putting together a 29er plus bike this Spring. Or I could ride from my house; it is 23 miles of gentle climbing (first 7 miles are paved) to get there.
In the beginning of MTBing (very first Stumpjumpers arrive), in southeastern Michigan, a good 80% of the first mountain bikers were avid road riders. I moved to San Francisco in 1988 and everyone was mellow for a few years. Somewhere around the early 1990s dirt riders started getting an attitude about us versus them. The road bike market in the city was flat or shrinking at that time as well, mountain bikes sold like hotcakes.

Sure, part of balancing. You agree then, that it takes a lot of input - balance and steering input - to stay upright on a bicycle, without the benefit of gyroscopic effect of the wheels. Yes, I agree. That was my point.

You have a very deep misunderstanding of how a bicycle works . Do some research. Learn something.

Exactly - that's a perfect example. Its much more difficult (requires more balance and steering input) riding a bike at 2mph than it is at higher speed, where the gyroscopic effect kicks in. But no, at 2mph there is little to no gyroscopic effect. Try riding no handed at 2mph - very difficult. Then again at 20mph - relatively easy. The difference is the impact of those gyroscopes you're riding on top of.

If we're going to let Sheldon provide the "mic drop" for this debate, it's this:

"That there are gyroscopic forces is evident from the riderless bicycle test in which a bicycle is shoved at a brisk speed (from another bicycle) and allowed to coast on its own. If the initial course is straight, the bicycle will continue this path until it slows to a speed where gyroscopic forces are too small to correct steering."

I'd be willing to let the myths survive if this thread would die.

I can ride at 2 mph very easily. There is no gyroscopic effect going on.

I've seen a figure skater moving along with one leg high in the air. No gyro there.

"Bike Forum threads we wish would die"

A bike with no gyroscopic effect is still rideable. The experiment has been done.

That’s good, because it can be self-stable as well, without gyroscopic effects.

https://www.science.org/doi/10.1126/science.1201959

Otto

See also:

https://www.wtamu.edu/~cbaird/sq/mob...ycle-balanced/

Otto

You completely glossed over a very relevant section of the same article:

To say that the gyroscopic forces of rotating wheels keep the bicycle upright ignores that roller skates are operated the same way and have so little gyroscopic moment that one cannot detect it. On ice skates, the argument fails entirely. Besides, a bicycle can be ridden at less than three miles per hour, at which speeds there is no effective gyroscopic reaction.

Yes, there are gyroscopic forces present, but they are very small and aren’t a factor when riding a bike.

Here is full text, with no sign-up and no paywall.

Thanks. I forgot about that.

Otto

Posting on the thread probably won't speed its demise.

Gyroscopic effects are just one aspect of a bicycle's dynamic handling characteristics, and like all the others, not really something that bicycle stability uniquely depends on. Other factors, such as trail and weight distribution, and plain old human balance, also contribute to the end result.

Actually, I think riding different bicycle setups no-handed is a good way to demonstrate the multitude of other factors involved. If it all rested on gyroscope, then the best bicycle for riding no-hands at low speed would be whichever one has the heaviest wheels installed. But in my experience, in the real world, it's a very poor predictor.

Uh, no? When I build a wheel, I put a certain kgf on my spokes which depends on the spoke's location and is the same regardless of spoke diameter, usually 100 kgf.- 120 kgf except for the NDS. The upper limit of this force is due to the rim. Obviously thinner spokes stretch more and thus the thinner the spoke, the smaller the change in tension as the wheel goes around. And because the change in tension is smaller, the fatigue at the J bend is lower. Thus one wants to use as much tension as the rim allows, regardless of spoke effective diameter. And thus heavier spokes will break from fatigue more often then lighter ones because they are not stretched as much. I think this is pretty well known by now. This smaller change in spoke tension is also a major feature of deep rims.

I run CX-Ray spokes on our tandem, which has deepish alu rims. Never had a rim crack, never broke a spoke, including the 14-15 DB spokes I used before I went to the CX-Rays. If it works on a tandem, it'll work on any bike, so all my bikes' wheels are spoked and tensioned similarly and similarly don't break spokes or crack rims. Oh - we also camp-toured on the tandem and on cobbles too. Never broke anything, though the cobbles sure sucked with 28mm tires. Wider fast tires weren't around then.

I do use more spokes than some. Our tandem came with Chris King 36H hubs, which I'll never change out, so we run 36H rims. My main single is 24/28, front radial. I like reliable.

They balance out and you're nobody

Exactly. Years ago I watched a video where a guy gently pushed an unladen bike off across a gym floor. Off it went staying up by itself. If he ran alongside and pushed on it laterally, it deviated from its course but recovered and continued on. Pretty convincing. That explains why a bike is so easy to ride and control. 2 y.o. kids can do it. A friend of ours 5 y.o kid, never been on a bike, got on one and simply pedaled away, turned, braked and everything. He's going to be, maybe is, another bike nut. Yeah, huge gyro forces on those balance bikes at 2 mph. I still see kids whose parents put on training wheels - worst thing they could do.

It's easier fixed - one keeps the bike essentially stationary but with a turned front wheel. Then it's a matter of back and forth on the pedals to keep it under you. Freewheel riders really need a crowned or canted street to take care of the reverse motion.

Yeah, I think we all know that trick.

I have seen stunt riders, trials riders, the people who ride parks and such, and even circus performers .... riding backward, upside down, on tight ropes, sitting still ..... all kinds of tricks. How can they sit and not move and not fall.? Oh, the gyroscopic effect of the spinning planet, of course.

Want to see some cool stuff watch trials motorcycles.

So yeah, there Is a gyroscopic force generated perpendicular to the axis of spin ... but that is not what holds the bike up ... believe me, I have crashed and even after bouncing, rolling, sliding, and grinding to a stop, when I looked at my bike the wheels were still spinning. Why didn't the bike pop upright from gyroscopic effect? Maybe ... because like the effect of added mass at the rims vs the bottom bracket or bottle cage, the gyroscopic effect simply isn't strong enough to keep a bike up if the rider doesn't balance it.

Carbonfiberboy ... I respect you much and most sincerely, but I challenge you to take one of your bikes (not carbon .... no assplosions :D ) and push it across a flat area for 30 feet ten times. Video it with your phone. I want to see this bike when never falls over.

I may be King Richard, but if you post that video i will admit I was wrong. I want to see it. Ten times, 30 feet, you push the bike and it doesn't fall over.

The whole point of that Sheldon article was to debunk your myth about the importance of gyroscopic effects in riding a bike. That's why it was written, but that obviously went right over your head. Remember what the Cambridge University Professor said too about this? Would you agree they know more about this than you do?

At this point I'm convinced you are either a troll or have some learning difficulties.

You missed the key point. Can you ride no-handed at 2mph? Probably not - no gyroscopes. Can you ride no-handed at 20mph? Sure, easily. There you go.

Also, I'm no ice skater but I'm pretty sure the physics of ice skating are completely different than cycling.