Trying to get an old '87 running again. Have worked out most of the electrical problems. Wirings ok, relay works, decomp sol. works, all accessories work. My question is on the starter. A silly one at that. Does the shaft come out of the starter to engage, and then recess back in, or does something in the engine engage the starter shaft? Does the starter have a built-in solenoid? The problem is the starter is staying engaged all the time. Off the bike to bench test, and starter spins fine, but should the shaft be popping in and out, or is it stationary? And how does the starter clutch work in this system?
New to bikes and bike mechanics---pardon my ignorance, but I'm trying to avoid spending $300 + on a starter only to find out it may not need one.

Thank you. It makes sense now. Earlier problem was it was cranking all the time by itself--fixed that short. I just wanted to make sure the system didn't work like on a Ford. Cars-bikes. 4 wheels-2 wheels. A lot of stuff is similar, yet a lot is very different. Thanks again for clearing that up. I may be riding this summer after all.