To replace a hub gear system with a regular gear system, you would need to remove the rear wheel with the hub gear and replace it with a wheel that has a cassette hub. You would also need to replace the shifter, derailleur, and shift cables to accommodate the new gear system. Additionally, you may need to adjust the frame to accommodate the new gear system, as hub gear systems often have specific frame requirements. It's important to ensure that the new gear system is compatible with the bike's frame and components before making the switch. **

No, it is not possible to convert a 7-speed gear system to a 21-speed gear system. The number of speeds in a gear system is determined by the number of sprockets on the rear wheel and the number of chainrings on the front crankset. A 7-speed system has 7 sprockets on the rear wheel and one or two chainrings on the front crankset, while a 21-speed system has 7 sprockets on the rear wheel and 3 chainrings on the front crankset. Therefore, to convert a 7-speed system to a 21-speed system, you would need to replace the entire drivetrain, including the rear wheel, front crankset, shifters, and derailleurs. **

Without more specific information or context, it is difficult to determine if the bicycle gear system is broken. Some signs of a broken gear system could include difficulty shifting gears, chain slipping, or unusual noises while pedaling. It is recommended to have a professional bike mechanic inspect the gear system to determine if it is broken and in need of repair. **

The SRAM gear system is not inherently defective, but it has been known to have some issues with reliability and performance in certain situations. Some users have reported issues with shifting and durability, particularly with certain models or components. However, SRAM has also made improvements to their gear systems over the years and continues to innovate and address any issues that arise. Ultimately, whether the SRAM gear system is considered defective may depend on individual experiences and preferences. **

A suitable system for outdoor raves would be a powerful and portable sound system that can cover a large area with high-quality sound. This could include a combination of large speakers, subwoofers, and amplifiers that can deliver the necessary volume and bass for outdoor settings. Additionally, the system should be weather-resistant to withstand outdoor conditions and have the capability to connect to various audio sources such as DJ equipment or music players. Finally, it should also have the ability to be easily set up and taken down for the convenience of outdoor event organizers. **

Yes, there is a form of extreme hiking camping known as backpacking or wilderness camping. This type of camping involves carrying all necessary gear and supplies on your back and hiking long distances to remote and rugged locations. Backpacking often requires a higher level of physical fitness, outdoor skills, and self-sufficiency compared to traditional camping. It can be a challenging and rewarding way to experience the wilderness in a more immersive and adventurous way. **

A twist shift gear system is a type of gear shifting mechanism commonly found on bicycles. It consists of a grip or handlebar-mounted shifter that allows the rider to change gears by twisting the grip or handlebar. This action moves the internal mechanism of the derailleur, causing the chain to move onto a different sprocket, thus changing the gear ratio. Twist shift gear systems are popular for their ease of use and intuitive operation, making them a popular choice for casual riders and commuters. **

A bicycle's gear system typically consists of a front chainring and rear cassette, connected by a chain. The front chainring is attached to the pedal cranks and has multiple teeth of varying sizes, while the rear cassette is attached to the rear wheel hub and also has multiple teeth of varying sizes. The gear shifters control the movement of the chain between the front and rear gears, allowing the rider to change the gear ratio and adjust the resistance when pedaling. This system allows the rider to easily change gears to accommodate different terrains and riding conditions. **