The Right Gear

When most people see rust or corrosion on a bicycle, they assume it was neglected or left out in the rain. While that's certainly a common cause, there's another culprit that often goes unnoticed: sweat.

The photo shown here is the inside of a bottom bracket shell, where the crank spindle passes through the frame. The material visible isn't dirt or rust - it's a thick accumulation of salt crystals that formed inside the frame after years of indoor riding. Left unchecked, this buildup can trap moisture, accelerate corrosion, and permanently damage internal components.

Human perspiration can be surprisingly corrosive. Over time, sweat can work its way into a bicycle's frame and components, leading to seized bearings, frozen seatposts, corroded hardware, and other expensive problems. If you're someone who sweats heavily—especially if your riding clothes are covered in a white, salty residue after a ride—your bike may be at greater risk.

Take a close look at areas where sweat tends to collect, particularly around the headset, stem, top tube, and where it can run down into the seat tube. Indoor training is especially hard on bikes because there's no airflow to evaporate perspiration. If you spend a lot of time on the trainer, use a sweat guard or towel to catch perspiration, and always wipe your bike down after each ride.