The split compression ring which is captured inside of the bearing cover, helps with variations in steerer tube diameters, sets preload, and locks the headset down solidly, ensuring no rocking nor creaking. The design acts as a tapered wedge for a secure hold and interface between the steerer and bearings, so nothing will come loose.
The split lip bearing incorporates a dual lip design, so the bearings get twice the protection. The design keeps grease in, and contaminants out, while still retaining low friction. The stainless steel angular contact bearings (5/32″ balls) are user replaceable, which is a very nice feature.
The 110 comes with 3 Interlok spacers, 2mm, 5mm and 10mm, although the 2mm is really a top cap that finishes off the stack. The Interlok spacers are interesting, since they snap into each other, with a sort of tongue (on the bottom) and groove (on the top) connection, and provide a solid and tight interface.
The bearing covers also have a set of o-rings, which prevent contaminant entry, and insure a tight and precise fit to the steer tube. The entire 110 weighs in at 95 grams with the tall top bearing cap, and 90 grams with the short, and this includes all 17mm of spacers with each stack.
Bearings 35.9 grams
2 mm spacer 2.5 grams
5 mm spacer 4.2 grams
10 mm spacer 6.7 grams
Short Bearing Cover 10.0 grams
Tall Bearing Cover 15.3 grams
Crown race 10.6 grams
Top Cap 8.6 grams
Bolt 7.9 grams
Compression Ring 3.4 grams
Total Tall stack 95.1 grams (w/ all spacers)
Total Short Stack 89.8 grams (w/ all spacers)
The steps to install the IS (Integrated) vary slightly from the TR (traditional press-in). The crown race and star nut (or self expanding wedge) are both installed on the fork, which is the same for either version. Next, one of the identical bearing pairs, with its angled side facing up is dropped onto the race, and the fork is inserted into the bikes headtube until the bearing self-centers in the lower tapered bore. The other bearing, with the angled side facing down, is slid onto the steerer tube until it self-centers in the upper bore. The chosen bearing cover (tall or short) with the installed compression ring is slid onto the steer tube until it touches the upper bearing, and then entire stack is sandwiched tightly together. It takes a little force to get the cover to slide down the tube, since the o-rings make it a tight fit. Due to the tightness, you no longer need to hold onto the fork. The appropriate number of Interloc spacers is added (snapping them together), and the stem is installed, followed by the top cap and its bolt. I tightened down the preload to approximately 5 N-M, and then eased off 1/4 turn. Tightening is done, so there is no play in the bearings, but still allowing the fork to turn smoothly, without any binding or excessive friction. Finally straighten the steering, and tighten down the stem pinch bolts to its specifications.
If the top bearing cover drags on the upper bearing cup (tapered bore), then the included spacer shims will need to be installed. The compression ring will need to be pulled off the bearing cover, and the shim is installed between the cover and ring. Cane Creek recommends occasionally rotating the bearings (top to bottom, bottom to top), in order to lengthen bearing life since the bottom bearing gets about 90% of the wear and tear in a headset. The major difference between the TR and IS is that the bearings are simply dropped into place in the headtube, and use the tapered bore in lieu of pressed in bearing cups.