Had the same thing happen 'bout 2 years ago. After cursing the 'cheap' batteries, buying a new starter, and cursing some more, I decided to check ALL the contacts from the battery to the starter, including the ground wire....... and that was where my problem was..... the ground wire on the battery is bolted to the frame under the rear fender. Even though the bolt was tight to the frame, there was corrosion and it had insulated the wire from having good continuity..... that simple..... easy to fix..... hard to find.