Oops...

[samrsnow]

I noticed the rotostart back plate on my STS came a little loose, then it totally locked up and wouldn't spin.

I try to start the engine a few more times and "crunch" wen't the small gear.

 

[Rolex]

When it locked up, it was probably the broken tooth caught in there.

 

[HPI_Newb]

I had this happen a couple of months back. What happened to mine was the roto start plate was loose enough to allow the main gear to come slightly un-centered, the 2 gears meshed too lightly and the gear broke. Gotta make sure everything is tight and centered.

 

[MudSlinger33]

This also happened to me. I made the mistake of using a drill on the savage, couldn't tell that the engine was flooded until it stripped a gear.