Question about vehicle spawn on servers

[Bricrue 0]

I have a private server up and running and had a question about the vehicle spawn. I've read things like there being four motorcycles per server yet in all of the locations I've looked, only one motorcycle has turned up. And the V3S Civilian isn't in either of the locations that others have said it is in. So are vehicles have a % chance to spawn in one of those locations each time the server is reset or do they just eventually spawn? How does this process work?

I do know that no one else has taken the vehicle already because currently I'm the only one playing. I'm thinking about adding a few people but I'm still trying to find the best way to go about finding trusted players who will agree to play by a rule set on this server. If anyone is interested in playing on this server send me a message. The idea behind this server is:

Zombies are based on slow walking zombies like seen in Night of the living dead and Walking dead TV show. There are also tons of Zombies so sometimes it does get a little scary if your not careful as you will find yourself in the middle of 100+ zombies.

We plan to hold weekly events where we have two groups, bandits and survivors. During these events the two groups fight eachother for control over rights to a select city. The winning group gets to claim this city and kill off the other group should they attempt to tresspass at anytime during the week.

PvP will be limited so that the game isn't sorely based off PvP and leans more on survival. The only time PvP will take place is during events or if you find someone tresspassing through your land.

Suggestions will be welcomed. Just not sure how to go about selecting those who would be interested at this time.

Sorry this post strayed from the main topic. Any help on the vehicle spawn would be appreciated.