Part: Honda CL / CB450 / CB500T Valve Stem Seals
Why You Need This: The dual overhead cam engine that Honda used on the CL / CB450 and CB500T is a marvel of engineering; it was like nothing before it and nothing like it has been produced since. Very few engines in history have use a torsion bar style valve spring, which makes the Honda CL / CB450 / CB500T engine different from its contemporaries from the same era. If you have the cylinder head of your engine off for some valve work, make sure to finish the rebuild right with a new set of valve stem seals. The valve stem seals are often overlooked on the CL / CB450 / CB500T engine as it is not obvious where they are or that they are even present. Swapping them out is easy once you have the head apart, and they should be changed to keep excessive oil from dripping on the top of the valve, which leads to a smokey engine and higher oil consumption. Valve stem seals are sold in sets of four (4), which will finish one engine. Pick up a new overhaul gasket set, cam chain, engine valves, and a pair of piston rings, and your top end overhaul will be done.
Installation Instructions: The valve stem seals are held in place with a "C" shaped bracket that is attached to the head with a 6mm bolt. The bracket does have a top and bottom side so make note of the orientation when removing it. The old seals may be stuck in place on top of the valve guide and may need to be gently pried off. Install the valve stem seals before installing the valves, make sure to put a some oil in the valve guide, and on the seal prior to installing the valve.