These Kartmaster ceramic hybrid axle bearings are a perfect fit for 40mm axles. With a 40mm inner diameter (ID) and 80mm outer diameter (OD), they're sold individually. Crafted with top - notch components, including #52100 chrome steel races, Si3N4 ceramic balls, an injection - molded polyamide cage, rubber seals, C3 clearance, and built to P6 precision. These SB - style insert bearings have an inner ring that's flush on one side. The Si3N4 ceramic balls are non - porous, non - magnetic, non - corrosive, and lighter than steel. They're also harder and spin faster with almost no friction. Si3N4 silicon nitride balls offer the best bearing performance. They're over 2x harder, 4x smoother, and about half the weight of steel balls. They won't crack, 'micro - weld', corrode, or pick up particles. They can even polish the races smooth if they get damaged. They reduce friction, run cooler, vibrate less, and get smoother with use. Note that these bearings need a short break - in period to reach peak efficiency.
Using these Kartmaster 40mm ceramic hybrid axle bearings is straightforward. Just fit them onto your 40mm axles. They're sold individually, so you can use as many as you need for your racing kart. During the initial use, keep in mind that they require a short break - in period. This is when the bearings 'settle in' to achieve the best performance. As for maintenance, since the Si3N4 ceramic balls are non - corrosive and can resist particles, they're relatively low - maintenance. However, it's a good idea to regularly check for any dirt or debris that might have entered the bearing. If the races show signs of pitting or damage, don't worry, the ceramic balls will likely polish them smooth again over time. Just make sure to keep the bearings clean and dry for optimal performance.
