couple different style starters i have found for the briggs 5hp motors. one style i have found is for horz-engines. you can see in the picture i swap out the 120v for the 12v,so i could use the correct nose cone starter that originally bolted up to my block.
also another style 12v motor i have found is off a vertical engine. what hp it may have been? not sure on that. just found the starter at a swap. good thing is it looks like i can swap it out on a 120v starter and make it into a 12v just like the other starter i did that too. the only differents is this starter has a quick 12v disconnect wires.
nice thing about the lighted coils on a briggs like roccosbike posted and the briggs i use with a lighted coil. they both put out dc current and about 2amps.
by using led lights on my bike i could still put enough amp's back into a battery to keep it charge,so my electric 12v starter could turn the bike over all day.
http://www.oldminibikes.com/forum/project-logs/12275-project-build-rear-springs-10.html