The starter clutch is not a part of the starter, but is instead a part that bolts to the flywheel. Since bike starters do not have the ability to disengage the flywheel gear and are always engaged, a one way bearing is used to allow the engine to run so that the gears can essentially float, but when the starter is engaged it locks.
In these engines cases they are on the back of said flywheel. Here is an example of one.
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