A picture is worth a thousand words. From Michael Moore's very cool Eurospares website ( www.eurospares.com ) here's an exploded view of the trans.
If you look closely you'll see the gears themselves will keep the balls retracted until the sliding shaft (#16 IN THE PHOTO) forces the balls outward and they lock into the cutaway sections of the gears. It works remarkably well as long as you keep the side cover shift mechanism tight and properly adjusted.
If you need specific question answered check out the Hodaka group , there is a world of knowledge with these guys. If it can be answered, you'll get it there. :worship: Also great parts sources.
So they sorta bounce off the inside of the gears all the time, until the shaft thing forces them out? I do understand how they engage the gears when called upon to do so. Somewhat elegant actually.
Perhaps as close to center as they are, they are not real motivated to "sling" out into the gears and cause mischief.