I noticed that some people are concerned about the high recall numbers they are seeing. The max recall shows the highest rpm from when you started the sled to when you shut it off. This does not meen it is the rpm at the end of the drag strip. Example: If you try your sled from a dead stop and nail it on a icy lake with poor traction you will experience excessive track spin. This is the rpm that the max recall is going to show. It is very possible to see 9000 rpm range numbers under these conditions. Once your sled starts to get traction and pull, your rpms will gradualy fall down to the normal operating range. I hope this helps.