Need to do a motor rebuild, or just want to replace your crankshaft seals Most people don’t know it, but loose, dry or worn out crankcase seals can allow air into the engine, causing them to run hot, or worse yet, lean. Rubber dries out over time, especially if the bike has been sitting. This is a MUST on a af16, when doing a rebuild on the bottom end. These are not chinese/taiwan seals, these are authentic OEM honda seals. Comes with one seal set, left and right.