A little information to share with CBX Keepers
As you might be aware original/early Hondas used the same model/frame designation, so a CBX750 was a CBX750 model and frame-wise.
Similarly, in all the versions, the engine also used a similar numbering system, though not always in line with the frame. For example, RC18 frame machines had RC17E engine or an RC17 frame machine had an RC17E engine, despite the fact the RC18 was a shaft drive and RC17 was a Chain Drive.
In 1984, Honda released two major different motorcycles in the 750CC class, one a chain driven, mono shock suspension, the other a shaft driven conventional dual rear shock. Frames were totally different. They shared the basic engine, electronics and front suspension, but RC17 machines got a more adjustable suspension.
RC17 Frame/Model: Any reference to this is a chain drive mono shock motorcycle.
RC18/20: These are all shaft drives, i.e. Japanese market shaft. CBX750 Horizon, CBX750P (Police) CB750 Nighthawk S Canadian, and CB700 Nighthawk S US. .
Any time you see an E designation after the code, i.e. RC17E, that refers to the engine model. While normally a frame and engine code is the same, i.e. RC17 has an RC17E engine; engines with the RC17E designation were put into Japan market shaft drive versions.
That is of interest, as there is a difference in gearing and clutch pack setup between the R17E chain and the shaft drives, but the RC17E engine designation is listed engine for all but US shaft drives. How the breakout of an RC17E chain drive engine, from a RC17E with the shaft drive converter occurred, I dunno (probably never will!). Suspicion is, it is in certain serial number ranges, but you would think the converter alone would warrant a different engine model id, but no…
CBX750F: RC17: 1984-86: Model RC17E engine, full 750cc 20,000 originally produced. Japan, Australia, Britain, Europe and Brazil. Frame has nothing in common with shaft variants. (but it did use frame tubes to move oil to/from oil cooler in the same manner), chain drive, with a mono shock.
Variations: (all with RC17 frame code )
CBX750FE and FG (semi faired machines)
CBX750FL (fully faired)
CBX750L(F-2F) BolD’Or: Fully faired, it continued production in Brazil till 1994, lot of local components used, mostly with 18 inch front tires.
CBX750 INDY: Brazil per above (hopefully more details to come)
CBX750 Horizon 84-86-RC18: Model RC17E listed engine model. Japan only home market 750cc shaft drive, conventional rear shocks and virtually identical appearance, layout per Nighthawk S.
Note: Key visual difference would be the leading front axle.
FRMAE: Massive SQAURE tube backbone, signature frame common to all the shaft drive variations.
This has to be the significant version that both the Canadian and US Nighthawk S are derived from. Going by frame codes, it obviously led to the 750/700cc Canadian/US variation, not the other way around.
CBX750P 84-2003 : Police motorcycle, appears to have an R18(X )frame designation. South Africa recently took delivery of another batch, so they are still being made, amazing.
Police versions, dated at least to 1988, very possibly latter). Conjecture this had some frame mods for the police gear supplied with machine. Engine Model is RC17E, it has the RC17 type clutch pack and or gear ratios are unknown. Suspected it has the full shaft drive clutch pack, and confirmation comes from a Polish source who had one, knew the S and the P.
Models of this type seem to have showed up all around the world, though none have been noted or reported in the US. (confirmed sittings, Thailand, Singapore, Australia (riding school) Israel, Turkey and Russia.
These came with a good front fairing, rear baggage (19 liter) in racks, sirens, PA system, their own unique instrument cluster (oriented for Police work) and special hand controls to operate the systems while riding (keeping hands on the handle bars where they belong!).
I am working on the 700SC Nighthawk version. Will upload soon. Hope this gives enough orientation of the bikes up there guys!!!!