Different CB Engine Types
This is just an educated guess.
CB-20 Single OHC Carbie N/A 993cc Leaded Found in G10 Charades
CB-22/23 Single OHC Carbie N/A 993cc Leaded & Unleaded Found in G11-G100 Charades
CB-50 I think some wreckers call a CB60 a CB-50
CB-60 Single OHC Carbie Turbo 993cc Leaded Found in G11-G10x Charades red rocker cover
CB-61 Single OHC Carbie Turbo 993cc Unleaded Found in G11-G10x Charades grey rocker cover
CB-70 DOHC EFI Turbo 993cc Unleaded Found in G10x GTti Charades
CB-80 DOHC EFI Turbo 993cc Unleaded Found in G10x GTti Charades
CB-90 SOHC Fuel injected 993cc N/A found in Europe and USA
CB-100 Just like the CB-50, some wreckers call a CB-70 or CB-80 a CB-100
Some pics from another site: http://home10.highway.ne.jp/cwl/engine.html
