- Worn or damaged gear teeth: Over time, the teeth on the gears in the transmission can wear or become damaged, causing noise when they engage. This is especially common in older motorcycles with high mileage.
- Improper adjustment of the transmission: If the transmission is not adjusted properly, it can cause the gears to mesh incorrectly, resulting in noise. This can be caused by a number of factors, such as a loose or stretched chain, or worn or damaged shift forks.
- Low fluid level: If the transmission fluid level is low, it can cause the gears to run dry, which can lead to noise and damage.
- Incorrect type of transmission fluid: Using the wrong type of transmission fluid can cause the gears to slip and make noise.
- Damaged bearings: The bearings in the transmission can also become worn or damaged, causing noise.
If you are experiencing a noisy fifth gear on your 1999 Yamaha 650 V Star, it is important to have it inspected by a qualified mechanic to determine the cause and get it repaired.
