Weird noise from starter

[JosephJoe]

Gentlemen,

Sometimes when I push the electric starter of my 1970 FLH Shovelhead it makes a loud banging noise, like if you hit with a hammer a piece of metal.
When I push again it starts normal without the noise.
It will do this approximately once out of every ten starts.

Does anybody know what could be causing this?

Thanks in advance,

Joe

[Rubone]

Check your auto advance unit. If it is sticking the starter is up against a brick wall....

[vph-d]

As Rubone stated, check your advance weights, you might find them stuck fully advanced, which kills the starter bendix.
VPH-D

[billpedalino]

You might also check the Bendix Drive as well.

[flathead tom]

missing teeth on ring gear on clutch hub

Gentlemen,

Sometimes when I push the electric starter of my 1970 FLH Shovelhead it makes a loud banging noise, like if you hit with a hammer a piece of metal.
When I push again it starts normal without the noise.
It will do this approximately once out of every ten starts.

Does anybody know what could be causing this?

Thanks in advance,

Joe

mabe missing teeth on clutch drum !!????

[jim d]

Wornout Bendix drive if you ever take one apart you will fine some small springs inside sometimes they are smashed or just weak, it will work fine in your hand but not under a load. If the timing is advanced to far or not returning it will make it kick back smashing those little springs. Or sometimes the springs just become too weak to hold the drive inside the Bendix.
Jim D.

[JosephJoe]

Gentlemen,

Thank you all for your expert intervision.
We have replaced the auto advance unit, and up to now the bike starts as it should be.

Thanks,

Joe