A variety of lubricants are available for skateboard bearings, but only a few are adequate. The right oil improves bearing operation and extends its useful life.
Because bearings have tiny parts and contact surfaces, only thin lubricants should be used. WD-40 should be avoided. WD-40, and similar products are not produced to act strictly as lubricants and may cause more harm than good.
Oils to use:
Thin oils made for small moving parts are ideal for skateboard bearings. Lubricating oils sold as electronic oil or sewing machine oil are great for bearings.
You can find similar oils for electric hair clippers and various small appliances that are excellent for skate bearings.
The reason these types of thin light lubricants work so well is their ability to work consistently at high speeds.
Thin lubricants made for speed require more applications bbecause they run out of the bearing sooner than slightly thicker oils. Thicker oils, such as 3-in-1, are better for skaters who are not into speed and who don't want to frequently service their bearings.
We may assume all bearing oils are going to work well. In some ways they work just fine, but for those who demand more out of a skate lubricant they may not work well at all.
For many skaters, it may not matter– lube is just lube. If bearings end up corroding unexpectedly, or if they roll slower, you may be using a low-grade bearing lube.
Lubricants to avoid:
Cleaning solvents and degreasers with lubricants have ingredients that counteract each other. There's a solvent trying to breakup contaminents and penetrants (light lubricants) trying to get between stuck parts to free them. The lubricants in products like WD-40 and Liquid Nails are so thin they can evaporate leaving bearings dry and suseptable to corrosion. These types of products are not suitable as bearing lubricantion.
Cooking Oils, are plant fats, and like plants and foods, they spoil. Which means they oxidize and break down quickly, which can lead to corrosion of the bearing. Avoid using all cooking oils.
Motor oil, or thick heavy oils, are made for large machines. Even a tiny drop of motor oil in a skateboard bearing will slow the bearing down. Because of its thickness, dirt will eventually cling to it and contaminate the bearing.
Greases, for example, including white lithium grease, can be a great lubricant for things other than skateboarding. Again, skateboard bearings have tiny moving parts and surfaces where thick lubricants, like white lithium greases, can slow a bearing down.
However, white lithium grease can be ideal for harsh weather conditions. The downside to white lithium grease is that, when it breaks down the residue left behind is very difficult to remove. Even dangerous solvents, like acetone, can't remove it. There may be some products out there that will, but it's not worth the headache. And adding more grease won't fix the problem.
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