Trek 3900

Explore, search and compare thousands of the world’s best mountain bikes here on Mountain Bike Database.

Compare prices, components, suspension, reviews, images and more on current and past MTB’s. You can even share reviews, comments and questions on mountain bikes. View and compare a huge selection of bikes from brands such as Trek, Specialized, Giant, Santa Cruz, Norco and more.

We strive to provide accurate and up-to-date information for mountain bikes on MTB Database. If you’ve spotted any issues, please let us know. We also include helpful tools, such as our frame size calculator, to assist you in choosing the right mountain bike. Bear in mind that these tools serve as a guide and simply provide a general indication. Refer to information provided by your bike manufacturer for the most applicable information for your bike.