Jan
i have a honda c50..but the engine serial number does not match the log book…how do i tell what the engine size is from the serial number on the engine?
Answer:
Actually,,the Displacement of the lil' Horizontal Motors are on Top,L/H side of the cylinder.
And the Engine Number does in fact denote Engine Size,,in nominal terms according to Model Name,,rather than actual displacement.
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As to why your numbers appear to "not match",,,there's a variety of reasons.
C50's are complicated to explain.
If you are intested and care to read,,I'll try to explain.
The engine number begins with the Bike's Model Number,followed by E
C50-xxxxxx would be a SERIAL NUMBER of the Bike
C50E-xxxxx would be an Engine Number
The Engines are produced as finished units,then inventoried.
Very common for MID-PRODUCTION changes to occur.
Same Engine–but with Detail Changes.
So the Engines all sitting in a Row in the C50 shelves will be,,
C50E-xxxxx,,,
Then they may CHANGE in some details/specs at # C50E-xxxYYY
Example:
1,000 Bikes may be Completed with
300 -xxxxx Engines,
and
700 -xxxYYY engines.
But the 1000 bikes are all still C50's of whatever Year,Series.
They're The SAME,,,but May HAVE some Production Differences.
Actually,,the Same applies to the Chassis
Ya think it's a nuisance to READ about,,,
There may be 2~3~4~5,etc "Different" Finished Bikes which are All the Same.
The Only Refference Material ID'ng them is Honda Parts Manual.
Which is why Honda always wants to know Frame and Engine Number when providing Replacement Parts.
Honda was Infamous for their "Superceding" of Parts.
A rare practice among the rest of the Jap Bike mfgrs.
There may have been 2~3 "'68 C50's" CHASSIS,,,
with 2~3 different Engines.
NOT substantial Differences,,,all "68 C50's" are the Same.
But with Minor DETAIL differences.
Then beyond That Variance,,,
there was a HUGE number of MARKET VERSIONS,
Jap,,,Russian,,US,,General Export,,,UK,,,Brazil,,,Transylvania,,LOL
Again,,,,those would ALL be "'68 C50".
AND,,the Frame & Engine Number Crossmatch would apply.
But also with each their own adaptative Version of Specific Market Version Details.
…………………………………..
The Basic reason the ENGINE NUMBER doesnt match the Log Book is based upon "All the Above".
In all the Documentation the Bike is I.D.'d according to FRAME Number.
That's Invariably going to be DIFFERENT than Engine Number.
Occasionally you'll find an Owner's Manual or Warranty Booklet which has had the ENGINE number "pencilled-in" by the Shop or the Owner,,,,for convenience of refference.
Simply Put,,,Engine's Number WONT match.
But the PREFIX will be the Same as Frame's
C50-xxxxxx Frame Number
with a C50E-xxxx Engine Number
If the "C50" Prefix of the 2 numbers Dont Match,,
then most likely the Engine has been changed.
A "C50-" BIKE,
with a C70E- or CT70E- engine is a Common Swap.
Those are 3sp Automatic 70cc engines.
Not unusual to find 4sp 50's ,65's,or 70's in OLD C50's.
Sometimes even 90's of some sort or the other
…………………….
Honda doesnt state engine size in their numbers,,,Not Directly,,nor in any encoded method.
But the Serial Numbers DO Begin with the Bike's MODEL.
And Coincidentally,,,,Most Honda's MODEL Name includes Engine Size.
Using engine numbers for example;
a C50E-……. is a 50cc (Nominal Size,,,not actual displacement)
a C65E-……65cc
a C70E- ….70cc
a C90E- …90cc
…………………………………..
There's several Exceptions to that
C100…50cc
c102….50cc
c105….55cc
c110….50cc
c200 …. 90cc
Those are all early 60's models,,by '70~71 they were gone
All those are also Pushrod motors,,Not Overhead Cam.
"OHV" overhead Valve
vs
"OHC" overhead Cam
……………………………
Another possibilty for a number "mismatch" is that the Engine has been Replaced.
There's quite a few "direct fit" (more or less) engines in that family.
50cc,55cc,65cc,70cc,90cc,110cc
OHV's and OHC's,
Automatic 3 spd
Automatic 4spd
4sp Manual
Dual Range 4 speed
…………………………………..
So,,Engine Number will indeed indirectly inform you of it's size.
IF,,IF it's a 2 Digit Prefix
c(50)e-
c(70)e-
But If it's 3 Digit,,,beginning with 1,,or "in the 100's" it's a 50cc engine
C-100,C-102,,etc
…………………………………..
The engine's actual original size is also cast into the Cylinder .
Here's some pics which show the location:
OHC 50—49cc
("newer style")
http://i14.ebayimg.com/05/i/000/d1/43/e2…
(Older style)
http://cgi.ebay.com/ebaymotors/HONDA-C50…
…………………………………..
OHC 70–72cc
http://i14.ebayimg.com/02/i/000/d0/9a/92…
…………………………………..
OHV 50– 49cc (the old c100,C110,etc Pushrod Motors)
Scroll down the page
http://cgi.ebay.com/ebaymotors/HONDA-C11…
Anyway,,,Don't be alarmed or concerned if the Numbers of Frame/Engine/paperwork do not appear to correlate to each other.
"NORMAL" for Frame & Engine to NOT match,,,especially on bikes before late 70's
However,,,all the Bike's Paperwork and Documentation Should reflect the FRAME Number.
THAT number is the Bike's actual Permanent ID.
It should NEVER Change.
Any discrepancy there is cause for concern.
Engine Numbers,,,can & do change from the Original for a variety of "Legit" reasons.
It's not necessarily any cause for concern.
SOME places include BOTH numbers on various registration documents—that would be the instance where a Replaced Engine number would need to be updated on the documentation…..which is no big deal & usually only necessary upon Title Transfer.
Sorry so long winded,, I hope any of that is useful to you.
Answer:
Honda doesn't typically put engine capacity in the cerial number. They use model number followed by a dash then their serial number. Look on the side of the cylinder and many times the engine size is stamped into the cylinder.
Answer:
as dean says look on the side of the cylinder at the bottom
Answer:
its on the cylinder side