Otaku Engineer in Great Tang Dynasty

In fact, this bike is really not easy to ride, not as good as the modern little yellow bike!

Since the pedals of this car are directly placed on the axis of the front wheels, the power of the car is mainly transmitted by the crank rocker linked with the pedals. When the pedal rotates, the front wheel also rotates. In this case, it is too difficult to make the car faster!

Had it not been for Li Zexuan's martial arts, he would have been tired of riding from Yunshan to Chang'an alone. Where could there be more energy to carry Lan'er around?

Modern bicycles are driven by chains, so there is a larger transmission ratio between the front and rear gears. Under normal circumstances, one revolution of the pedal will drive the rear wheel to rotate several times. The so-called variable speed bicycle is on the rear wheel. A flywheel is added to the place where it can change the number of teeth.

Y represents the gear ratio, C represents the number of teeth of the driving gear, and n represents the number of teeth of the passive gear. The relationship between them is expressed by a formula, that is, Y=c/n. For example, the wheel disc of a car has 48 teeth and the flywheel has 16 teeth. Substituting into the formula, the gear ratio can be calculated as 3. That is to say, pedal the roulette for one week and the flywheel for three times, which means that the rear wheels rotate for three times.

Although increasing the gear ratio can speed up the bicycle, don’t ignore it. The chain drive in this case is a laborious lever. The greater the gear ratio, the more laborious the pedaling. Based on this comprehensive consideration, in actual situations, regardless of the bicycle For the models on the side, the gear ratio is about 2-4.

The gear ratio of the transmission car is adjusted by changing the gear ratio, so as to achieve the purpose of saving effort or increasing speed.

Another problem is that for the rotating parts of the bicycle body, the only thing the workshop can do now is roller bearings, and ball bearings cannot be done. The rollers also caused the bicycle in Li Zexuan's hands to run rather jerky, the handlebars were not flexible, and the frictional kinetic energy of the wheels was lost. This makes this thing harder to ride.

"Brother! Look! Look! Isn't that Sister Changle and Brother Prince?"

When riding to Dongshikou, Lan'er suddenly cried out excitedly.

"哧~!"

Li Zexuan heard Lan'er's voice and quickly squeezed the brakes. A hoarse rubbing sound rang through the street, and the bicycle stopped immediately.

"Ouch~!"

Due to inertia, Lan'er's head hit Li Zexuan's back all at once, and the little girl couldn't help letting out an exclamation.

"Cheng Qian? Where is it?"

Li Zexuan supported the bicycle with his right foot, turned his head and asked.

"Huh! Brother smelly, don't talk to Lan'er when parking!"

Lan'er rubbed his head and said with a small mouth flat.

Of course, the little girl is definitely not really angry. After complaining to Li Zexuan, she said: "No, that's not the prince brother and... hey! Brother, they are coming to us!"

In fact, without her, Li Zexuan has also found Li Chengqian and Changle among the crowd. The siblings were followed by two guards. The guards were holding several brocade boxes. They must have been out of the palace to go shopping and they just finished shopping.

The previous hoarse brake sound instantly attracted the attention of their brother and sister. When they saw Li Zexuan and Lan'er here, they leaned over here.

"Ah! Brother Xiaoxuan! What kind of car are you pushing~?"

Changle ran all the way, looking at the bicycle beside Li Zexuan in surprise, said.

"Yes! Xiaoxuan! Why have I never seen this kind of car?"

Li Chengqian also walked to Li Zexuan at this time, and when he saw Lan'er sitting on the oddly shaped car, he felt surprised and couldn't help asking.

"The prince brother is really stupid! This car is called a bicycle, it can run on its own, and it runs fast!"

Seeing that Li Chengqian and Changle were both unseen in the world, Lan'er suddenly felt a deep sense of superiority. She couldn't help but say, "A-niang said that the prince's brother and Changle's sister were born in the royal family and their identities are distinguished. Come, the royal family is not as good as ours!"

The little girl’s thoughts are always so simple and innocent. She has bicycles in her home, but the royal family does not, so obviously her home is better than the royal family!

"Haha! That's right! This is the bike! The workshop just made it, so it's normal that you haven't seen Cheng Qian!"

Li Zexuan held the bicycle with one hand, patted Lan'er's head with the other, said.

"Bike? This car can really walk on its own?"

Li Chengqian looked at the bicycle carefully, a little disbelief.

He always felt that this kind of car would fall to the ground when people let go. How could it be possible to walk on their own?

In fact, this is not to blame for his short-sightedness. The main reason is that ancient people often saw horse-drawn carriages. He has formed a mindset. The bicycle has only two wheels, and the two wheels are arranged one after the other. Naturally, it is far worse than the horse-drawn carriage. Even more stable~www.ltnovel.com~ Before Li Zexuan spoke, Lan Er couldn't help but retort: ​​"Why can't it! Lan Er and her brother just came here on this bike!"

Changle covered his mouth and smiled: "Sister Lan'er, it should be the car that Xiaoxuan elder brother ridden. Are you in a car?"

Lan'er's face was not red and heartbeat, and said, "Yeah! I just want to express this. Sister Changle, you are so understanding!"

This girl's mouth can be so sweet that Changle is irritated by her sweet heart, "Ha ha! Lan'er, how does it feel to sit on this bicycle?"

Lan'er raised her head, thought for a while, and said, "Well! It's quite comfortable... It's just a bit cold!"

To be fair, a bicycle is indeed faster than a horse-drawn carriage, but this thing is definitely not as warm as a horse-drawn carriage.

This was a kind of cute and clever answer, which immediately amused everyone.

"Sister Changle, do you want to try it too? It's really comfortable~?"

Seeing everyone laughing, Lan'er thought they didn't believe what she said, so she said again.

A touch of emotion flashed in Chang Le’s eyes immediately. Li Chengqian glanced at Chang Le inadvertently. His heart suddenly shook, and he hurriedly said, “Ahem! Chang Le, it’s not too early, if the father and mother were the same If I haven't seen you for a long time, I should worry!"

As the elder brother, Li Chengqian has actually discovered that Changle’s feelings for Li Zexuan are different. He can’t tell whether it is the attachment to the eldest brother or the feelings between men and women, but no matter what, Changle should not go with Li Zexuan. Too close. As for things like sharing a car, it is even more impossible!

"Yeah~! Then brother Xiaoxuan, sister Laner, goodbye~!"

Chang Le shook his thin lips and said softly.

In a pink palace dress, she looks even more pitiful in the sunset