Troubleshooting
400 Error Responses with Solr 5.4.x
The most common cause of 400 errors from Solr is the lenght of the text field that Aspire tries to feed, the default "text" field type has changed and in Solr 5.4.x it uses "strings" which don't allow big strings to get indexed. To fix it modify the type of it to be "text_general" (in the managed-schema.xml file) and that should resolve your problems.
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