I have loved cycling since I was a kid.

My first bike was a BMX-style children's bike with auxiliary wheels. On the first day I got it, I used a wrench to remove the auxiliary wheels and rode it in circles on the square.

Later, dissatisfied with riding a small bike, I set my sights on my mother's women's bike, a blue and white steel frame, 26-inch thin-tire curved handlebar city bike. At the time, I was not tall enough to sit on the saddle and pedal, so I spent most of the time riding standing up. The large wheel diameter brought faster riding speeds, making me the fastest rider in the neighborhood kids' bike team.

After entering junior high school, because the school was relatively far from home, I was basically driven to and from school by my parents in the first semester. According to the provisions of China's "Road Traffic Safety Law Implementation Regulations", children who are 12 years old can ride bicycles on the road. After the first year of junior high school, I turned 12, and classmates started to appear riding bikes to and from school.

There was a boy in my class who shared similar interests with me, liked sports, and loved to tinker with electronic products (he owned a Nokia smartphone, a Sony perfume bottle MP3 player, and a Sennheiser IE80, among other high-end products, in 2011 and 2012). His family was relatively well-off, and his father supported him in riding a bike to and from school, so he got a Giant TCR 8.0FS folding bike.

This car brought me a shock, with its aluminum alloy folding car body, road bike gear set, disc brake wheel set, and front fork with shock absorption...... These components were eye-opening, considering that the Giant bikes students rode on the road at that time did not have such configurations, and having an ATX 660 was already very good.

I started applying to my parents for the right to ride to and from school, but due to safety concerns, I didn't get to go to school independently until I graduated from junior high school. However, since our family's old bike was too old, I still managed to get a folding bike of my own: the Dahon Speed 8, also known as SP8 or P8.

The SP8 features a chrome-moly steel frame, 8-speed SRAM X7 gearing, V-brakes, and comes equipped with the Shiwen large apple 2.0 tires. The seatpost also has an integrated pump function, making it very practical and classic. Since I often ride with classmates and enjoy mountain biking, the 8-speed gearing on the P8 was slightly struggling on uphill climbs. Later, I modified the front chainring to a double chainring, added a Microshift front derailleur, and replaced the tires with 1.5-inch narrow tires to reduce rolling resistance.

The good times didn't last long, and in my first year of high school, the school held a sports meeting. Due to special circumstances, I had the opportunity to ride my P8 to school. At the time, my classmates often left their bikes unlocked in the non-motorized vehicle shed, so I didn't bother to lock mine either. On the day of the sports meeting, many people from outside the school and other schools entered the campus, and after the event, I discovered that my P8 had been stolen.

This incident had a significant impact on me. On the one hand, I was heartbroken that my carefully modified bike had been stolen, and I regretted not locking it. On the other hand, it was my first experience with the harsh realities of society, which made me fearful of losing valuable items every time I went out.

After losing the P8, I still wanted to ride a bike from time to time. I mentioned it to my parents a few times, and after the mid-term exams in my first year of high school, my mother bought me a second folding bike. However, due to the fear of losing it again, she didn't buy me a high-end model worth over 3000 yuan. Instead, she bought me a cheaper Giant TCR 8.0RD, which is an entry-level model. Compared to the old FS model, the RD has a different frame design, and the wheelset uses a special 22-inch size. The gearing is an 8-speed SRAM X4 groupset.

This Tern 8.0RD has gone through several moves and has been preserved until 2025, with over a decade of age. I don't have much affection for it like the P8, and in the middle, I only replaced the inner and outer tires and chain due to rust and blowouts, without touching other parts. This year, with the arrival of a baby, I plan to renovate this Tern under the pretext of riding with my child in the future, replacing the transmission and sprocket, swapping out the 20-inch wheelset, and solving the problem of the strange noise in the head tube.

After disassembling the bike, I discovered that it is not compatible with the 20-inch P8 wheelset, although the openings are all 74/130mm, the V-brake seats are not compatible. The Tern's frame has disc brake mounts, so in theory, I can replace it with a disc brake wheelset to solve this problem, but after buying the wheelset, looking at the brand-new large apple tires that come with it, I really want to install a P8 to make up for the regret of 10 years ago.

So I started looking for a suitable large P8 frame, it seems that from a few years ago, the manufacturer changed the name of the P8 to D8, and also launched a low-end "youth version" with an ugly paint job, and added a so-called "vest line" that claims to increase the frame's rigidity. As we all know, the manufacturer does not sell folding frames separately, and most people will choose to buy a low-end P8 youth version and then modify it later. I searched all over Xianyu (a Chinese second-hand marketplace), but couldn't find a well-preserved steel P8 frame, some frames from over a decade ago can still sell for over 1,000 yuan, which I find hard to understand.

I started to notice another brand - "Feng Xing" (English name fnhon), which is very similar to Dahon, after researching, I found that this brand should be related to Dahon, the early models (KC2018/KCD2018) are very similar to Dahon's K-frame, but after 2016, they also have original designs such as ant legs and Y-shaped frames, which is a relatively interesting domestic brand. Feng Xing provides separate frame sales and offers a 5-year warranty, the same model can choose steel frame/aluminum frame and disc brake/V-brake, it can be said that they have given enough space for DIY.

Finally, I placed an order with an agent for a brand new KC2018 chrome-moly steel V-brake version frame, which came with a wheelset and free shipping for 850 yuan. I chose the yellow color because I had seen a very bright orange SP18 before, and I had always wanted to have a folding bike with a bright color frame. Another 16-inch bike for my leader was found on Idle Fish, where I discovered a seller who had a stock of antique bike frames. He had done a postal green spray paint version himself, and it came with a wheelset for 428 yuan, including shipping. The other parts were mostly sourced from Idle Fish, mainly from dismantled P8 and K3 Plus Mini (16-inch, 349 yuan) bikes. The overall price of both bikes was controlled within 2000 yuan, which is still relatively cost-effective.

Finally, I will release the parts list and price reference, excluding labor costs and various tool fees for installation and maintenance: