Sep 05, 2013 at 12:09 PM
I replaced my lower CAAD10 headset bearing (link to thread) because after cleaning using the method JP describes in the post above, it was still gritty. So sometimes if it's gritty, it's not getting any better: the internals are deformed and more grease won't repair the fault.
In the end I just bought a new headset bearing. Just the bottom one. I bought a top of the line one from Cane Creek. They have a tool on their website that tells you which of their products to buy for your bike. http://www.canecreek.com/headset-fit-finder You can also call them. I spoke with a charming lad from North Carolina. This is what I ended up ordering, through Ride Brooklyn rather than online: http://www.ebay.com/itm/Cane-Creek-110-Int-Bottom-1-1-4-47mm-Head-Tube-Headset-Tube-/390564393078?pt=Cycling_Parts_Accessories&hash=item5aef73b076.
Once you get the part # from the headset manufacturer, Ride can order it. Ride did not have a Cane Creek catalog; you'll have to figure out exactly which part you're ordering.
I went with that particular headset bearing--and not the default FSA/Cannondale/unbranded ones that most shops stock--because this headset bearing has a rubber seal between the crown race and the bearing. This is in addition to the lip seal covering the races themselves. This additional barrier will increase the life of the bearing, I hope. The stock CAAD10 bearing puts the lip seal right on the crown race; anything that gets into the gap between the fork and the head tube pretty much immediately begins working its way into the lip seal. Not so when there's a rubber seal in between the crown race and the bearing! Excellent design, Cane Creek.