Newfix

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Posted: Nov 27, 2020 at 1:23 Quote
Just so you know, I design bikes professionally and have designed and raced human-powered vehicles, so you don't need to cover the basics for me!

Posted: Nov 27, 2020 at 1:27 Quote
Fixed Gear, despite its seeming simplicity, is a transmission that is very difficult to understand and physically describe. You will not find this anywhere in the articles. When I tried to understand this transfer, I discovered for myself the phenomenon of energy recovery in Fixed Gear. This scientific discovery can be documented - it is only a matter of time and payment for the services of scientific workers - reviewers.
Even with the smallest impact on the cranks, a moment of momentum arises in the bicycle wheel. The wheel is essentially a flywheel, and the flywheel itself serves as an energy store - it is a mechanical battery. And since the connection between the wheel and the connecting rods is rigid, the momentum energy is accumulated in the man-bicycle system.
And since energy is accumulated, it can be used for high-speed movement (recuperation is the reverse return of energy). For this, a second gear stage with an intermediate shaft is supplied. The recuperation works only on the plane and when moving down. There is no recuperation when moving up.
As for the two-position landing: no one has ridden in such modes yet, so it makes no sense to rigidly compare them with road bikes. These new landings are just as strikingly different from highway landings as recumbent landings differ from highway landings. Each landing has its own "zest."

Papers in wheels are fun.

Posted: Nov 27, 2020 at 1:35 Quote
When a person is pedaling a bike with a freewheel, the drive mechanism is always engaged, making it functionally identical to a fixed gear when pedaling. How is your design different?

Posted: Nov 27, 2020 at 1:35 Quote
R-M-R wrote:
Just so you know, I design bikes professionally and have designed and raced human-powered vehicles, so you don't need to cover the basics for me!

Then it will be very pleasant for me to talk with you and I may ask for your help in any design issues. Don't be offended about the basics, I'm pretty boring and I always look back - at least how many times I come back to go forward again.

Posted: Nov 27, 2020 at 1:37 Quote
R-M-R wrote:
When a person is pedaling a bike with a freewheel, the drive mechanism is always engaged, making it functionally identical to a fixed gear when pedaling. How is your design different?
My patented single skating gear
https://yandex.ru/patents/doc/RU2727544C1_20200722
Link to Bike Forums site, a little about Newfix mechanics
https://www.bikeforums.net/alt-bike-culture/1212094-new-fixed-gear-newfix-2.html

Posted: Nov 27, 2020 at 1:49 Quote
Thank you for the link. Thankfully, Google Translate did an excellent job.

Unfortunately, it is my strong opinion this design offers only one, small advantage, yet creates numerous, large disadvantages. It is not my intention to be impolite, only to state my opinion.

If you choose to pursue this project, I urge you to find a way to position the cranks much closer together. For example, one set of cranks can be wider than the other, allowing their rotations to overlap. You may even be able to directly connect the cranks with gears, instead of sprockets and chains.

Posted: Nov 27, 2020 at 2:14 Quote
R-M-R wrote:
Thank you for the link. Thankfully, Google Translate did an excellent job.

Unfortunately, it is my strong opinion this design offers only one, small advantage, yet creates numerous, large disadvantages. It is not my intention to be impolite, only to state my opinion.

If you choose to pursue this project, I urge you to find a way to position the cranks much closer together. For example, one set of cranks can be wider than the other, allowing their rotations to overlap. You may even be able to directly connect the cranks with gears, instead of sprockets and chains.

Thank you very much for your help. Your method with overlapping the connecting rods is clear to me and it is very good. It follows from my discovery of the recuperation effect. Any scientific discovery in mechanics entails a lot of innovations and mechanical devices based on it. I agree that in its current incarnation, Newfix is ​​not the "Navel of the Earth", not something frozen, but on the contrary, an evolving solution.
To begin with, I will still try to achieve the calculated indicators on the existing apparatus. When there are records and the fact that my project is working well, you can already deal with various innovations and improvements to improve. The main thing is that I launched this idea into the World: "The Moor did his job."

Posted: Nov 27, 2020 at 2:38 Quote
Thinking about my previous statement, it may not be possible for the cranks to overlap because they do not rotate at the same rate. I leave this for you to solve!

I remain skeptical, yet I commend you for your initiative and I wish you well. tup

Posted: Nov 27, 2020 at 2:55 Quote
R-M-R wrote:
Thinking about my previous statement, it may not be possible for the cranks to overlap because they do not rotate at the same rate. I leave this for you to solve!

I remain skeptical, yet I commend you for your initiative and I wish you well. tup
I understood. The bottom line is a different set of connecting rod widths. This is a good idea, but not yet embodied. Like any technical solution, this option may have its advantages and disadvantages. Need calculation and training of pedaling with legs wide apart. By the way, I already have a similar solution - see the sketch of a stepper with three spaced platforms at the above link.

Posted: Nov 27, 2020 at 3:17 Quote
There is a major omission in your process.

First, you are basing some of your calculations on the achievements of Denise Mueller-Korenek. She did not accelerate without the aerodynamic assistance of the vehicle; she was fully in its slipstream when she reached her maximum speed.

Reaching a high speed is not a matter of total energy input. The energy stored as flywheel kinetic energy is small and it does not make the rider go faster; the best it can do is help the rider sustain the average speed when going uphill.

The average speed of the rider is determined by how much power is produced and how little of it is wasted. Therefore, the first and most important step is to help the rider produce maximum power via ideal body position. Next, the steady-state power requirement must be optimized, primarily by reducing aerodynamic drag. For example, professional time trial racers are not restricted by ratios that are too low - they can select custom sprockets as needed - they are restricted by power output and air resistance. Current time trial bikes are nearly the best solution for this, other than recumbent bikes. A fixed gear (track) pursuit bike is slightly better than a time trial bike with multiple sprockets, but only a percent or two.

Time trial racers produce over 1.5 MJ during a one hour time trial. For one percent of that energy to be stored as flywheel energy in the wheels and drivetrain, the bike would have to be traveling more than Mach 2.

Another way to look at the situation: if you assume the aerodynamic drag of your bike and rider is the same as for a traditional bike, the power required to travel a certain speed is the same. Where is does the extra energy come from? If energy is stored, then the rider had to be working even harder than normal to overcome air resistance and store additional energy.

The problem is even more severe with the stepper drawing you have provided. The air drag will be higher, due to the upright posture, so the energy required to overcome the drag is higher. The drivetrain of a time trial bicycle is already over 95% efficient at converting the rider's energy into work. This work overcomes:

1. Air resistance - your design does not improve on this.
2. Tire rolling resistance - your design does not improve on this.

The only ways to go faster - or the same speed with less effort - are to improve the power output of the rider or to reduce losses from air drag, drivetrain friction, and/or tire rolling resistance.

Again, my intention is not to be impolite. There appear to be serious errors in the physics of your system.

Posted: Nov 27, 2020 at 4:00 Quote
R-M-R wrote:
There is a major omission in your process.

First, you are basing some of your calculations on the achievements of Denise Mueller-Korenek. She did not accelerate without the aerodynamic assistance of the vehicle; she was fully in its slipstream when she reached her maximum speed.

Reaching a high speed is not a matter of total energy input. The energy stored as flywheel kinetic energy is small and it does not make the rider go faster; the best it can do is help the rider sustain the average speed when going uphill.

The average speed of the rider is determined by how much power is produced and how little of it is wasted. Therefore, the first and most important step is to help the rider produce maximum power via ideal body position. Next, the steady-state power requirement must be optimized, primarily by reducing aerodynamic drag. For example, professional time trial racers are not restricted by ratios that are too low - they can select custom sprockets as needed - they are restricted by power output and air resistance. Current time trial bikes are nearly the best solution for this, other than recumbent bikes. A fixed gear (track) pursuit bike is slightly better than a time trial bike with multiple sprockets, but only a percent or two.

Time trial racers produce over 1.5 MJ during a one hour time trial. For one percent of that energy to be stored as flywheel energy in the wheels and drivetrain, the bike would have to be traveling more than Mach 2.

Another way to look at the situation: if you assume the aerodynamic drag of your bike and rider is the same as for a traditional bike, the power required to travel a certain speed is the same. Where is does the extra energy come from? If energy is stored, then the rider had to be working even harder than normal to overcome air resistance and store additional energy.

The problem is even more severe with the stepper drawing you have provided. The air drag will be higher, due to the upright posture, so the energy required to overcome the drag is higher. The drivetrain of a time trial bicycle is already over 95% efficient at converting the rider's energy into work. This work overcomes:

1. Air resistance - your design does not improve on this.
2. Tire rolling resistance - your design does not improve on this.

The only ways to go faster - or the same speed with less effort - are to improve the power output of the rider or to reduce losses from air drag, drivetrain friction, and/or tire rolling resistance.

Again, my intention is not to be impolite. There appear to be serious errors in the physics of your system.

I have already tested my system in practice and it works:
https://www.strava.com/activities/3984591362
The results may not be so impressive, but I see them, in you not yet. This is not a mistake or delusion. This is the discovery of a new phenomenon, which is not clear to society, because it is new and still unknown to anyone. Because without this phenomenon, the physics of fixed gear is not clear. This transmission is not deservedly forgotten (only the track), and its properties are not fully understood.
Fixed gear transmission and freewheel transmission are completely different systems from the point of view of physics and the main mistake is to compare them directly and make hasty conclusions. This disease affects everyone who rides on a free wheel and has never ridden a fixed gear. Even the fixers are mistaken. Because fixed gear is a very complex gear.
I am not touching the stepper motor yet - it is a derivative of the original project and I will get to it later. This is more a fun project than a fast one. Therefore, for now, I leave it and do not touch it.
I'm not mistaken about Denise Müller-Korenek, but on the contrary I read a lot about her records and I know the essence. According to my link from another site, everything is clearly written, I even gave a picture with the calculations of its transference. I know at what speeds and what drove her. I just took the idea of ​​the intermediate shaft, and the rest of my calculations go only to muscular strength.

Do not consider it arrogance, I can ask you: did you go to Fixed gear? Because if you did not drive fixed gear, our entire conversation will be meaningless. It will be like a conversation between the blind and the deaf. If you have ridden a fixed gear, I will have a lot of leading questions for you about this ride - until we get the truth.

After all, I am a fan of fixed gear and I only have fixed gear bikes, I have three more besides Newfix.

Posted: Nov 27, 2020 at 4:16 Quote
Oh yes! I forgot to say: I rode something that no mortal has ever ridden - a fixed gear with two fights! Bicycle 17.5 kg, I am 100 kg, age 58, old old man, crushed 6.8 gear! In inches it is 176! He did not die, but overclocked the machine with a pinched (overtightened) chain to a speed of 47.5 km / h on Strawa.

Posted: Nov 27, 2020 at 4:24 Quote
You definitely should enjoy riding something unique that you created. That's exciting!

I remain unconvinced about the performance benefits. Thank you for discussing your creation. I will leave you to pursue it and I hope you find success.

Posted: Nov 27, 2020 at 4:45 Quote
R-M-R wrote:
You definitely should enjoy riding something unique that you created. That's exciting!

I remain unconvinced about the performance benefits. Thank you for discussing your creation. I will leave you to pursue it and I hope you find success.

I will give you confidence in the performance benefits. Already in a test drive, I overtook my standard fixes in speed. They have an average speed of 20 km / h, maximum 40 km / h.

When I picked up the finished Newfix from the factory, I did not check everything thoroughly. I was in a hurry to make the first race. The chain was taut. But even on such a tight chain, I made an average speed of 22.2 km / h and a top speed of 47.5 km / h. This is beyond what I could squeeze on my fixes! This is already the result of the advantage of Newfix at least over the usual fixed gear! I walk slowly like a turtle towards my goal, but persistently. Next season I will have to share my results with you. To kill skepticism in you.
Although skpsis is very important in the design of such devices. It filters out obviously inoperative and failed constructions. I'm also a skeptic. My profession is a mechanical engineer (а mechanical engineer is more of a technologist). Therefore, I am a barrier to my designers. They can design anything, and I land them under technology, materials science, and so on ...

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