Nice job Paul, but it looks like the battery is now a permanent fixture, and would require the use of a spanner to remove it.
I am very puzzled by the increase in performance though, did you by any chance shorten the battery leads or adjust the controller setting?
I can fully appreciate how changing its position would affect the balance and handling of the bike, but repositioning the battery should have made no difference whatsoever to the actual performance or efficiency of the motor, unless you have inadvertently improved the battery lead connection by simply disconnecting and reconnecting the power plug during the process of the conversion:
When engaged and disengaged, the crown contact surfaces of Anderson SB Connectors "over wipe," thus providing a self cleaning action. To ensure the continued benefit of this feature, clean the contact surfaces and lubricate the connector. Use a "white" lithium grease, which may be obtained from hardware stores and automotive parts suppliers.
Anyway, it's nice to hear that your Smart Pie is performing so well.
Alan