It seems to have the standby capacity, I don't think the environment in the lawn tractor is any more harsh than the motorcycle.
Having said that, at a particularly tight financial period in life I ran one in my 81 R100RS. It lasted about 3 years, but was only about $19.00 in 92 or 93.
It gave up on a weekend ride with little warning. I do not know why, but it was so cheap I did not care. I simply push started my ride and ran with out lights to get home.
I have toggle switches to kill the lights. Head light, tail light, running lights, all separate. Probably the only thing that saved me. The bike had enough juice to run.
After that I put in a Yuasa, then an Odyssey after that. Still have the Odyssey but have not run that bike in 4 years.