You might try recruiting a proxy who lives close to the seller to exert your claim of the property, and trying to get the police to respond. Or you or they might document the case, by confirming the serial number and immediately filing a small claims case demanding the bike or proceeds of any sale plus (if allowed in the state) added penalties.
You'll need solid evidence, so acting as a potential buyer and documenting the serial number would be a place to start.
__________________
FB
Chain-L site
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