charging same battery with two motors?

[Dukdog]

I run a 60 and an 8 off one battery. I really like to have a backup everything. I run my 2 downriggers off a different battery. I carry jumper cables as a backup so I can start a motor. I have an autopilot off the main battery also and I minimize it's use to setup, fighting and landing fish or during operation on the big motor. I'm not sure if the charging rate off my kicker would keep up with full time AP operation.

[JeffM]

I would like to see some solid data showing a kicker charging the battery would damage the big motor. In my boat I have the starting battery as well as two deep cycle for the 24v trolling motor. In an emergency you can always start off the deep cycle. I am in the same boat with my kicker but need more info before I bring a fourth battery on the boat just for starting a kicker. Seems overkill.