It's self adjusting, hence the name. However, it is one of the many parts that are replaced in Triumph's upgrade kit for the Rocket III, which sounds like you will be a recipient of. Contact your nearest dealer and tell them what you have. Triumph should take care of it all whether or not you are in warranty.
BTW, don't take the adjuster out without the cam cover and front covers off of the engine. The cam chain will likely fall off of the crank gear or one of the cam gears.
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