If you need a crown race and you can get this brand and style with the dust seal get it! Way better than the cheap ones and protects your bearings from dirt and watter.

Was a little hesitant at first but turns out in fits great!

Top quality easy fit

Solid product. I have abused it and it has held up heat so far. I'm using a grocery getter bike to do downhill races. It would not have made it this far without this bearing set.

This is the one. Cane Creek 110 series. Top of the line.52/40 refers to the diameter, in millimeters, of the inner and outer surfaces of the bearing. It works with a tapered headset with a 1½" lower bearing and an inner race angle of 36 degrees (standard 45/36 bearing).It differs from others in that it has a firm silicone lip at the outer edge that presses against and seals the outer race of the bearing- the inner surface of it seals against the steering tube. So, it makes the lower end of your head tube essentially water and dust proof. Good thing too, your front tire blasts that area with dirt and water every time you ride, it really needs that protection. Standard crown races are just a flat piece of metal (angled at the center to fit the lower angle of your bearing seat) with no seal that allow water and dirt to get in there easily. Most bike mechanics try to seal it by caking a pound of grease in there. That's a messy, sloppy, amateur procedure.If you carefully add a small amount of waterproof (marine) grease on the upper surface of this and the lower surface of the bottom bearing, stick them together then wipe out any excess grease that squeezes out (so you don't create a dust magnet), between the silicone seals and that grease, your bearing is 100% protected, full stop. Take it apart, clean it out and re-grease it as standard maintenance every 6 mos or so.This is not specific to Cane Creek bearings, I'm using it with an FSA. Massive upgrade.I've lost count of how many lower headset bearings I've had to replace because water and dirt got into them and they rusted and/ or wore out. Not any more...Easily installed/ seated with a length of 1½" PVC pipe. Gently tap in place with a soft mallet until it evenly seats.