Standard or compact disc? Understand the different types of bicycle teeth disk everyone is strange, is riding a bicycle, the pedal pressure through the crank to turn the sprocket blade, teeth (t) number is the main difference between different teeth disk. Different dental discs have different effects on the characteristics of the bike and the riding experience. Most road bikes come with dual teeth discs, the larger discs give you a larger, harder to turn tooth ratio, allow you to move further with each turn, and it's good for sprints at higher speeds (which don't last as long). The smaller platter gives you an easier tooth ratio to turn, but the pedal moves a shorter distance per turn - so it is suitable for riding at lower speeds, including uphill. Standard dental disc Standard dental disc has 53 teeth (or 52 teeth) large disc and 39 teeth small disc. This used to be the norm for road cars and the choice of professional drivers (who used larger platters for time trials or flat road stages). 53/39 dental disc is now rare outside the professional drivers, so the standard dental disc is actually a past name, and now ordinary riders are not equipped with the so-called standard dental disc. Both Shimano and CP only offer standard dental trays in their premium kits. Professional drivers have more power and need more speed, so in Shimano's latest DA package, a 54/40 option is offered. Compact disk The compact disk has a 50-tooth outer sprocket and a 34-tooth inner sprocket. Compact dental discs are very popular because they are easier to turn. And with the popularity of high-tempo riding, this smaller dental disc is more popular and puts less strain on the knee. A compact disc can be knocked out during a quick descent. The three largest kit manufacturers offer compact dental discs in all of their road kits, which reflects their popularity. Semi-compact disk A semi-compact disk, sometimes called a mid-compact or artificial professional, has a 52-tooth outer sprocket and a 36-tooth inner sprocket. The semi-compact dental disc has become popular in the last few years and it has helped many amateur drivers progress. Shimano and CP offer semi-compact dentals on all kits except the entry-level road kit. Smaller than the 50/39 compact disk are the small disk, they are usually 48/32 or 46/30, can lower the overall gear ratio a little, making climbing easier. Gravel trucks and some hardtail mountain bikes are the main users of this type of gear, suitable for more complex, steep sections. Triple disc The triple disc consists of three sprocket pieces as the name suggests, and Shimano offers the option of 3 double discs for low-end kits clairs, Sora and tiagra, not 50\39\30t. CP has until recently started offering Athena with 3 double dentals (52\39\30) for road cars. Superlink doesn't have that kind of system. The triple disc has a very small sprocket blade, which also means that it has more repetitive tooth ratios, which is a good choice for a climbing bicycle such as a station wagon. This setup is simpler, the chain doesn't rub on the non-existent front pick, and they make better contact between the thick chain and the sprocket pieces because their specially designed sprocket pieces have high, square tooth edges that engage the chain earlier. This 1x system is rare in road vehicles, but it has a good application effect in gravel and off-road vehicles. Replacing sprockets Today's gear trays are relatively simple to replace (requires an Allen wrench), ensuring that your new gear trays are compatible with the drive system (sprockets have different bolt diameters (BCD) and bolt spacing) by simply replacing the pressure trays, you can turn the standard gear trays into compact gear trays. Don't forget, if you change the sprocket, remember to adjust the position of the front wheel and the length of the chain.