Hey guys, I'm new to the forum, but not new to 400's or Mechanics.

I've just began the first stage of a nut and bolt rebuild on my Honda CBR 400RR-L NC29. First job was to clean up the crankcases back to a shiny finish, however, whilst cleaning the upper crankcase, I came across the engine number which I found to be a bit odd. Its on the left above the clutch side as you look at the engine with the cylinders facing you, and it starts with NC23E.

It matches the logbook and has been in there since 1990 as far as I can tell through paperwork and the logbook, but does this mean they are NC23 crankcases? Also, how different are the NC29 and NC23 motors?

Thanks in advance :)

These bikes evolved from the fist cbr-r the cbr400r aero which had the designation nc23 and although the engine changed somewhat from the aero to Triarm to Gullarm they all start with nc23 engine numbers

Awesome, thanks Yakama!

I was looking at pictures of the 2 engines thinking the crankcases were different, and thought perhaps mine was stamped wrong!

Cheers mate, that's a big relief!

bizarrly I had a 29 with a 29 prefixed engine number I'll see if I can find the pic

Here is some usefull info

http://www.vsource.org/VFR-RVF_files/Bcbr400rr-mi.htm