help with 1978 atc90

[Jimmyd]

Hi folks,I just bought a atc90.Now the problem I have is hes got a big 12volt battery on the back,Im not sure why its there.He has one wire to ground and 1 coming from the stator.
It will not run without the battery(no spark)Is the battery actually taking place of the points?
This battery is alot of weight on the back for my son.
Hes always pulling wheelies but not on purpose lol.
Any help.
Thanks

[Mr_RPM]

wow that is weird, never heard of such a thing

[Texas 200x]

I don't see how a battery would take the place of points. I would put it back the way its suppose to work. Search for the wiring diagram and go from there.

[86trizinger]

Cars use a battery and alternator to create the power needed. Small engines use a stator to generate the power with no battery needed.

The stator creates the current needed for the bike to run. If it never creates any power then the bike would never get current or spark. They may have bypassed or hooked into the stator with the battery to create a power source.
Chances are they rigged something up to fix a bad stator.

Forgot to add. The points works kind of like a distributor. It needs power from some where to fire. So its not being used to replace the points.

[Mr_RPM]

talked it over with the oldman and the generating coil to the stator probably broke so they rigged up a battery to take its place, does the battery die eventually? check out all the generating systems and fix them, then you shouldn't be battery dependent

[Jimmyd]

talked it over with the oldman and the generating coil to the stator probably broke so they rigged up a battery to take its place, does the battery die eventually? check out all the generating systems and fix them, then you shouldn't be battery dependent

Yes the battery actually dies.
Im going to take the cover off and see what kind of nightmares behind it.
Its almost like opening a jack in the box Im scared and excited at the same time.
Thanks for all the help.
I'll let you know what I find.

[Mr_RPM]

i have had some bad stator luck on some Yamaha warriors in the past, the problem probably wont be visible to the eye, the stator can be tested with a resistance test, and then simply needs to be replaced.
now my 84 110 has the CDI and the generating coil is up by the cam, the stator down by the flywheel only does the light. not sure what your model with the points is like but find whatever charges electricity for the spark plug is what your looking for.