So just wondering if anyone conclusively knows how honda achieved an extra claimed 5 bhp on the later 97/98 model.

I've read speculation that the ram air system was revised and ignition remapped.

​​​​​​I've owned, built and tinkered extensively on both platforms, only difference i've seen on the intake/tune is that 95/96 seems to use profoundly taller middle velocity stacks vs the later having a couple of mm difference. As for any possible ignition differences it's kind of unquantifiable unless cdi part numbers are identifiable and known to which they belong.

Havent compared parts numbers on the ramair/airbox but they appear to be identical on both.

I cant imagine stacks on an already well designed system and perhaps advanced ignition being worth 5bhp.

Yeah, anyone shed some more light on this? Purely curiosity driven.

 

 

Cant imagine many have thought about this or are interested but here you go.

Turns out i was comparing a 98 bike to a 95 with 98 parts ​​​​​​

Checked parts fiche for airbox, cdi etc and confirmed different parts numbers.

Dug out some spares and noticed instantly that early vs late have different grills on the ram air scoop. Going to compare all the parts side by side when i get a chance, i suspect any difference will be marginal.

Identifying cdi/ecm
Area codes.
A= USA
AC= california models [emissions restricted]
Often on parts fiches you get AC and A models, A how the rest of America recieved the bike and more often than not, most of the world. This is why workshop manuals usually have california specific parts and "49 states" sections. (or however many states america has)

There's a whole array of codes you can have for area: https://www.motorcyclespareparts.eu/...identification

With that in mind for parts numbers A = the world minus california.

A- 1997/1998 cdi part number: 30410-mal-a01
AC- 30410-mal-a81
A- 1995/1996 cdi part number: 30410-mal-671
AC- 30310-mal-771

So 95/96 and 97/98 have different cdi boxes

Found an old decipher which indicates the first line being mr hondas code for the platform, followed by a region identifier.

Random cdi code plucked from the internet:
MALA EC
971G
5317

MAL A EC
MAL is our cbr 600 Platform -
A im unsure of -
EC being England -

971G shows which variant of cdi it is, havent sussed out what it refers to yet, there's a couple of different possible codes on this line and might have different ignition advance curves. Im pretty sure certain regions get certain codes. Its likely california gets a its own code, the rest of the world gets the generic code with possible exceptions to japan. theres also the hrc cdi having a 14,500
Rpm limit which i cant find much info on.

5317 is a date stamp.
we know its a 90s bike so we start with that in mind.

5 indicates year, its the 90s so it becomes 1995.
3 indicates 3rd month, so its march.
17 indicates day.

This example being 17th march 1995. The important part being ability to identify year.

The double digit months ie october November and december are shown as X, Y or Z




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