Are footpegs superior if you don't pedal?

[ebike4healthandfitness]

This is an easy experiment you can do yourself. Get a beach cruiser or other simple bicycle that rides nicely, and try it with different size wheels. You can even use shorter cranks when pedal strike becomes a problem.

That idea sucks.

By reducing wheel size you are also reducing trail.

Then there is the tire and rim change which will also impact handling

Trail works adequately well within a very large range of values, and this experiment wouldn't change it by a very large amount.

When are you going to stop the BS and making stuff up?

Do you even know what trail is?

 

[Chalo]

What are you talking about, kid? Build a few unique bikes from scratch and then get back to me. I've been doing this stuff since the '80s. I only suggested an easy experiment that you could use to step up your game. I don't assume you are capable of more than that.

 

[BalorNG]

What are you talking about, kid? Build a few unique bikes from scratch and then get back to me. I've been doing this stuff since the '80s. I only suggested an easy experiment that you could use to step up your game. I don't assume you are capable of more than that.

To be fair this is indeed 'not everything being equal' experiment, though I agree with 'trail works wihtin large range of values', and 'trail' as conventionally defined as 'distance from steering axis to contact patch projected to the ground' is about as useful as description of a man as 'bipedal animal without feathers'. Technically correct and even somewhat useful, but gives you exactly zero idea what it actually stands *for* and what exactly makes it important (and why too much can be bad!)

Because *I* did my homework

 

[ebike4healthandfitness]

What are you talking about, kid? Build a few unique bikes from scratch and then get back to me. I've been doing this stuff since the '80s. I only suggested an easy experiment that you could use to step up your game. I don't assume you are capable of more than that.

'trail' as conventionally defined as 'distance from steering axis to contact patch projected to the ground' is about as useful as description of a man as 'bipedal animal without feathers'. Technically correct and even somewhat useful, but gives you exactly zero idea what it actually stands *for* and what exactly makes it important (and why too much can be bad!)

Reducing trail reduces stability, but increases agility. Increasing trail does the opposite and increases stability, but reduces agility.

Changing tire diameter affects trail (small diameter tires reduce trail and large diameter tires increase trail) so that different fork offsets and/or head tube angles have to be used in order keep trail within the narrow range for the intended application.

Lowering center of gravity and reducing trail at the same time is a bad experiment because the effect from the reduced trail (reduced stability, increased agility) is a confounding variable. This is why I think Chalo is writing stuff like lowering center of gravity hurts stability when the rest of the world believes opposite....because his flawed experiment makes him believe it.

 

[BalorNG]

What are you talking about, kid? Build a few unique bikes from scratch and then get back to me. I've been doing this stuff since the '80s. I only suggested an easy experiment that you could use to step up your game. I don't assume you are capable of more than that.

'trail' as conventionally defined as 'distance from steering axis to contact patch projected to the ground' is about as useful as description of a man as 'bipedal animal without feathers'. Technically correct and even somewhat useful, but gives you exactly zero idea what it actually stands *for* and what exactly makes it important (and why too much can be bad!)

Reducing trail reduces stability, but increases agility. Increasing trail does the opposite and increases stability, but reduces agility.

Changing tire diameter affects trail so that different fork offsets and/or head tube angles have to be used in order keep trail within the narrow ideal range for the intended application.

Lowering center of gravity and reducing trail at the same time is a bad experiment because the effect from the reduced trail (reduced stability, increased agility) is a confounding variable. This is why I think Chalo believes lowering center of gravity hurts stability when the rest of the world believes opposite.

You are parroting what every 'bike mag' tells you, without truly understanding anything what trail actually DOES. To be fair that's 99% of people do, including those article writers, so you are not special. Singletrack dynamics is a surprizingly complex and often counterintitive science, so you are excused in your ignorance, but not in spounting it with such applomb.

Trail has nothing to do with 'agility', it comes from other factors, and you have quite stable arrangements with HUGE negative trail (to a point at least, namely very high speeds) - python-type recumbents.

Or you can try a lowracer recumbent with slack steering angle and huge trail despite small front wheel... Enjoy your total lack of EITHER stability OR agility unless at 40mph I guess

Lack of *control* at slow speed (and stability of python recumbents) comes from 'flop' that is a function of trail and does opposite thing of that trail does. Only way to uncouple that is put steering tube vertical (or close to vertical).
... and do not even get me started about virtual pivot steering arrangments that might have nothing remotely recembling 'trail', but more than 'just rideable' - they allow something that no conventional steering arrangement can do.

Steering and balancing a bike a very complex 3d phenomena full of conflicting forces. Reducing it to 'trail' or CG is woefully, laughably simplistic.

 

[ebike4healthandfitness]

What are you talking about, kid? Build a few unique bikes from scratch and then get back to me. I've been doing this stuff since the '80s. I only suggested an easy experiment that you could use to step up your game. I don't assume you are capable of more than that.

'trail' as conventionally defined as 'distance from steering axis to contact patch projected to the ground' is about as useful as description of a man as 'bipedal animal without feathers'. Technically correct and even somewhat useful, but gives you exactly zero idea what it actually stands *for* and what exactly makes it important (and why too much can be bad!)

Reducing trail reduces stability, but increases agility. Increasing trail does the opposite and increases stability, but reduces agility.

Changing tire diameter affects trail so that different fork offsets and/or head tube angles have to be used in order keep trail within the narrow ideal range for the intended application.

Lowering center of gravity and reducing trail at the same time is a bad experiment because the effect from the reduced trail (reduced stability, increased agility) is a confounding variable. This is why I think Chalo believes lowering center of gravity hurts stability when the rest of the world believes opposite.

You are parroting what every 'bike mag' tells you, without truly understanding anything what trail actually DOES. To be fair that's 99% of people do, including those article writers, so you are not special. Singletrack dynamics is a surprizingly complex and often counterintitive science, so you are excused in your ignorance, but not in spounting it with such applomb.

Trail has nothing to do with 'agility', it comes from other factors, and you have quite stable arrangements with HUGE negative trail (to a point at least, namely very high speeds) - python-type recumbents.

Or you can try a lowracer recumbent with slack steering angle and huge trail despite small front wheel... Enjoy your total lack of EITHER stability OR agility unless at 40mph I guess

What you write makes no sense because now you are talking about recumbents.

Remember we are trying to control variables not add more of them!

 

[BalorNG]

What you write makes no sense because now you are talking about recumbents.

Remember we are trying to control variables not add more of them!

Unless recumbent in question is has 3 or more wheels and not a free-leaner, it still has singletrack dynamics... in fact, for 3 wheels having CG as low as possible is, indeed, an absolute must.

Anyway, regarding 'having everything equal' except for CG:

Take a huge backpack, fill it 30 pounds of potatoes or something
Wear it, ride around, notice the handling

Remove it, get panniers, fill them with same amount of potatoes, ride around.

How about 'potatoes to potatoes' comparison?

 

[speedmd]

'potatoes to potatoes

Yummy. Ours are cooking now and I am getting whiffs of them. Soon I hope. Best wishes to all for a good meal today.

As far as I see, the topic is boiled down to looking at both the hand and foot positions-distances apart, and there relation to axle positions per relative wheel base as being key to what influence ones mass has over bike - riders trajectory and stability. Having more mass loading higher or further from center will force itself to endo more easily. Must be modeled on some dynamics program somewhere?

 

[Chalo]

Changing tire diameter affects trail (small diameter tires reduce trail and large diameter tires increase trail) so that different fork offsets and/or head tube angles have to be used in order keep trail within the narrow range for the intended application.

If you'd actually made things and tried them rather than imagining them, you'd know that the conventional wisdom about trail is only the broadest kind of generalization. Changing wheel diameter without changing other factors does affect trail, but the effect of trail also changes for different wheel diameters and even tire widths and pressures.

Nobody talks about the effects of frame drop as a function of head angle and fork offset, but this effect is quite pronounced, and it changes with wheel diameter even when trail is held constant. I had to learn about this factor by making bikes and discovering it empirically.

Excessive trail isn't stabilizing, but the opposite. Very short trail isn't necessarily destabilizing and doesn't necessarily result in nimble steering.

If you were a capable bike builder, I might suggest doing the experiment I suggested, but with a range of fork offsets to maintain equal trail. I kind of doubt you'd find the difference between that and keeping the same fork to be very noticeable or compelling. But I didn't suggest that because it's clear that you don't actually make stuff and see how it works.

 

[BalorNG]

Changing tire diameter affects trail (small diameter tires reduce trail and large diameter tires increase trail) so that different fork offsets and/or head tube angles have to be used in order keep trail within the narrow range for the intended application.

If you'd actually made things and tried them rather than imagining them, you'd know that the conventional wisdom about trail is only the broadest kind of generalization. Changing wheel diameter without changing other factors does affect trail, but the effect of trail also changes for different wheel diameters and even tire widths and pressures.

Nobody talks about the effects of frame drop as a function of head angle and fork offset, but this effect is quite pronounced, and it changes with wheel diameter even when trail is held constant. I had to learn about this factor by making bikes and discovering it empirically.

Excessive trail isn't stabilizing, but the opposite. Very short trail isn't necessarily destabilizing and doesn't necessarily result in nimble steering.

If you were a capable bike builder, I might suggest doing the experiment I suggested, but with a range of fork offsets to maintain equal trail. I kind of doubt you'd find the difference between that and keeping the same fork to be very noticeable or compelling. But I didn't suggest that because it's clear that you don't actually make stuff and see how it works.

Yea, fork flop is highly underappreciated parameter.
http://yojimg.net/bike/web_tools/trailcalc.php

And here is some wisdom from Mike Burrows
https://www.youtube.com/watch?v=AZrvLdX7B3E

For those that REALLY want to know why flop is bad, trail is good and what they actually DO (among other things) to give better/worse controllability - this paper is great read:

http://www.bicycle.tudelft.nl/ProceedingsBMD2010/papers/patterson2010application.pdf

 

[ebike4healthandfitness]

Changing tire diameter affects trail (small diameter tires reduce trail and large diameter tires increase trail) so that different fork offsets and/or head tube angles have to be used in order keep trail within the narrow range for the intended application.

If you were a capable bike builder, I might suggest doing the experiment I suggested, but with a range of fork offsets to maintain equal trail. I kind of doubt you'd find the difference between that and keeping the same fork to be very noticeable or compelling.

I do find it humorous that you wrote "I kind of doubt" at that spot in the paragraph (and sentence).

Well at least at this point you are finally being honest about being a BSer.

 

[Chalo]

What I meant was that you seem not to be very insightful or observant, so subtleties that disagree with your preconceived/only notions would probably elude you.

 

[Chalo]

What I meant was that you seem not to be very insightful or observant, so subtleties that disagree with your preconceived/only notions would probably elude you.

Why don't you demonstrate these ideas you didn't come up with instead of declare them like they're true (when you don't actually know)?

 

[ebike4healthandfitness]

Why don't you demonstrate these ideas you didn't come up with instead of declare them like they're true (when you don't actually know)?

It's common knowledge.

Here is one such example discussing the relationship of wheel diameter and fork offset to trail.

https://www.pinkbike.com/news/To-the-Point-Wheel-Diameter-VS-Fork-Offset.html

 

[Chalo]

Why don't you demonstrate these ideas you didn't come up with instead of declare them like they're true (when you don't actually know)?

It's common knowledge.

Here is one such example discussing the relationship of wheel diameter and fork offset to trail.

https://www.pinkbike.com/news/To-the-Point-Wheel-Diameter-VS-Fork-Offset.html

There you go with other people's oversimplifications again. Maybe try again with some direct experience.

 

[ebike4healthandfitness]

Why don't you demonstrate these ideas you didn't come up with instead of declare them like they're true (when you don't actually know)?

It's common knowledge.

Here is one such example discussing the relationship of wheel diameter and fork offset to trail.

https://www.pinkbike.com/news/To-the-Point-Wheel-Diameter-VS-Fork-Offset.html

There you go with other people's oversimplifications again. Maybe try again with some direct experience.

You didn't even read the article did you?

It mentioned a very specific example that began the process for these relationships to be understood. It only took a wheel diameter change of 3" for people to start taking this seriously. Then fork manufacturers went from having only one offset to a multitude of offsets.

 

[Chalo]

It gives a very shallow, top-level understanding predicated on a bunch of other arbitrary and fashion-driven bike geometry assumptions. The reason that MTBs from the mid '80s are pretty much all the same but all different from MTBs of the early '90s, which are pretty much all the same but all different from '10s MTBs, etc., etc., is not based on understanding the principles. It's a lot of monkey see, monkey do. Which is what you're doing, except for the doing part.

 

[ebike4healthandfitness]

Chalo if you had understood this relationship you would never have proposed the experiment of taking a 26" beach cruiser and replacing with smaller diameter wheels for the purpose of proving lowering center of gravity doesn't improve stability.

Basically your "doing" and "empirical evidence" is a huge waste of time because you don't isolate variables.

The doing you should be doing is reading. Otherwise you are wasting our time by forcing us to find the flaws in your process. The flaws in your process that cause you to come up with conclusions that go against common sense and common understanding.

 

[Chalo]

I have done more reading on these things that you have, because I've been reading about them for 40 years. But I've tried all these things, worked them to their limits and beyond, and figured out many places where the conventional wisdom is oversimplified, mistaken, or only valid in limited circumstances.

You? You just took some guy's word for it, and then began yelling at us like you actually knew anything.

Here are just a few of the things I've made that required an applied understanding of head angle, fork offset, and trail:













Do you have anything to show?

 

[ebike4healthandfitness]

I have done more reading on these things that you have, because I've been reading about them for 40 years.

No you haven't.

And this idea you had about lowering center of gravity not improving stability was just laughable.

 

[Chalo]

So? What have you done? Let me guess.

Nothing?

And this idea you had about lowering center of gravity not improving stability was just laughable.

That only works for multi track vehicles. But thanks for playing!

 

[ebike4healthandfitness]

And this idea you had about lowering center of gravity not improving stability was just laughable.

That only works for multi track vehicles. But thanks for playing!

Says Chalo.

And this determined by Chalo building a bike (using flawed logic like your idea for a 26" beach cruiser with smaller than 26" wheels, but no changes in fork offset) which "proves" you are right and everyone else in the world is wrong. :lol:

When are you going to stop the BS son? You have already been caught red handed once in this thread already.

 

[BalorNG]

And this idea you had about lowering center of gravity not improving stability was just laughable.

That only works for multi track vehicles. But thanks for playing!

Says Chalo.

And this determined by Chalo building a bike (using flawed logic like your idea for a 26" beach cruiser with smaller than 26" wheels, but no changes in fork offset) which "proves" you are right and everyone else in the world is wrong. :lol:

When are you going to stop the BS son? You have already been caught red handed once in this thread already.

Ok, that's is. This is guy is verified troll.
Please refrain from interacting with him (AKA feeding him).

 

[ebike4healthandfitness]

And this idea you had about lowering center of gravity not improving stability was just laughable.

That only works for multi track vehicles. But thanks for playing!

Says Chalo.

And this determined by Chalo building a bike (using flawed logic like your idea for a 26" beach cruiser with smaller than 26" wheels, but no changes in fork offset) which "proves" you are right and everyone else in the world is wrong. :lol:

When are you going to stop the BS son? You have already been caught red handed once in this thread already.

Ok, that's is. This is guy is verified troll.
Please refrain from interacting with him (AKA feeding him).

Real frame builders (not ones that are 100% confirmed not to understand the relationship of fork offset, wheel diameter and trail) know that a low bb height increases stability:

https://calfeedesign.com/geometry-of-bike-handling/

https://thebicycleacademy.org/blogs/news/speed-vs-stability-gcn-at-the-bicycle-academy

 

[donn]

Real frame builders (not ones that are 100% confirmed not to understand the relationship of fork offset, wheel diameter and trail) know that a low bb height increases stability:

https://calfeedesign.com/geometry-of-bike-handling/

Excuse me, up to now weren't you saying low center of gravity increases stability? Now it's bottom bracket?

Here's the a quote from this link from your post above Speed Vs Stability - GCN at The Bicycle Academy.

Now balance the hammer in a dynamic situation by placing it on the end of your finger. You will notice that it is easier to balance with the head above the handle. This is not because it is more stable in a static sense, but the dynamic system of you controlling the movement of the point support of the hammer produces what could be perceived as a more stable result. This is because the greater distance between your finger and the centre of mass means that larger movements are required from your hand to regain static stability when the hammer starts to fall. This in turn means that the system is inherently less sensitive to small movements, which makes it easier for us to coordinate iteration towards a stable solution.