Does Wheel Bearing Grease Go Bad? – A Brief Overview
Wheel bearings are responsible for bicycle wheel rotation and are essential to your bike’s performance. Taking good care of your bearings is an important step in bicycle maintenance.
It is important to know that wheel bearings come in two common forms, closed bearings and open bearings. Wheels with closed bearings have lubricants sealed into them. This form of bearing cannot be re-lubricated without compromising the wheel bearing’s effectiveness. On the other hand, wheels with open bearings require re-lubrication to maximize performance.
What Is Wheel Bearing Grease?Wheel bearing grease is a lubricant sold in semi-solid state, and it has high chemical stability. It is a suspension of oil in wax, and it protects your wheel bearings from heat and water.
A good wheel bearing grease helps to minimize the quantity of heat generated by friction. This helps to increase the durability of the bearing. There are different types of wheel bearing grease, but they all serve the same function.
Wheels with open bearing require the use of new grease when the old grease has been contaminated. If you have the right type, you can change your wheel bearing grease yourself because the grease is easy to handle. A good grease is able to keep the loose bottom brackets in place for a long time.
Wheel bearing grease has a long shelf life of more than a decade. Despite this long shelf life, some grease still goes bad. The cause of decomposition in a wheel bearing grease that goes bad is not the chemical components, but the container’s contamination.
The primary reason why wheel bearing grease goes bad is heat. When the grease is stored in areas of high temperature, it can undergo separation and contamination with moisture. At separation, floating oil becomes visible on the grease and it is no longer usable. The separation may be due to high temperature, but also long storage, high humidity, and oxidation exposure.
Is It Advisable to Use an Old Tub of Grease?
Suppose you want to use an old tub of grease. In that case, you need to examine if the grease is still usable according to the prescribed shelf life. Check the shelf life by referring to the manufacturer’s instructions.
If the grease tub has not exceeded its shelf life, and the grease looks consistent, you can use it. Even in cases where the stated shelf life has been exceeded, you could still use the grease if it maintains its consistency and does not contain dirt or contaminants. If you’re still unsure about using an old tub of grease, you could visit your local bike shop for guidance.
Since most bikes come with sealed bearings rather than open bearings, you won’t need to worry about re-lubricating too often. However, grease may still leak out of sealed bearings once the bearings’ own shelf life has been exceeded. If your bike performance slows down over time, be sure to check the bearings.
It is generally agreed that the best form of grease is sealed in a tube with a cap, rather than a tub. Tubes minimize the grease exposure to air, and the reduction of air exposure then minimizes oxidation, ensuring your grease lasts for longer.
Credit and Useful Reading: https://www.bearingtips.com/shelf-life-affect-bearings-lubricants/