So here is the latest info from Ducati,
 I recommend contacting them with questions regarding your bike.    (tech@ducati.com)
 The investigation continues,............................... 
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 Dear Mr. Griffin,
 unfortunately we are not able to explain what SPTC means, moreover we confirm you the bike is a 851 SBK.
 Regards, 
 ELENA CATTAGNI     
TECH@DUCATI.COM  Customer Service
 Ducati Motor Holding Spa
 Borgo Panigale - Italy
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 Dear Mr. Griffin,
 from our archives this Ducati  851 SUPERBIKE BIPOSTO was produced on the 31 October 1989.
 Regards, 
 ELENA CATTAGNI          
TECH@DUCATI.COM  Customer Service
 Ducati Motor Holding Spa
 Borgo Panigale - Italy
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