ca77 engine halfs switch question

[LOUD MOUSE]

I SAID LOOK AT THE """""""""""""INSIDE"""""""""" OF THE CLUTCH COVER as the subject was a line in a engine case.
So ya have a line in a case and ya are going to your METAL EXPERT feller and test for a crack.
OK..
I don't talk in riddles at all.
I have apx. 35 clutch covers and ALL have casting LINES on the inside which to some would look to be cracks.
Well ya take a little time and a piece of sand paper or similar and ya will find that CRACK is nothing more than a LINE in the casting.
Riddles your donkey Jensen!!!!!!!!!!!!!!!!!!!! ............LM

Loud Mouse,

You talk in riddles, I checked my clutch cover, what am I supposed to see ?
I see nothing in particular, except that the "crack " runs to the clutch center bearing.

I do not have the clutch cover with this crankcase, but picked just one.
LM, help me out here with conclusions.

Jensen

[jensen]

Loud Mouse,

First of all thanks for your opinion about the "cracks", it confirms my presumptions.
A dear friend of my is a metallurgist, and he's always interested in such questions.

Yes I admit, I could have done that, but that would destructive research, if an expert looks to it, better leave it untouched.

I don't understand the expression "riddles your donkey", but I'm sure you meant it either positive or in a positive humorous way.

Talking in riddles is more a Dutch expression, I have to start thinking more international.

As stated in my previous mails, I am always looking for parts which differ from the standard. Add that up with my insatiable hunger for information, knowledge and mix it with perseverance and stubbornness and the result is me, an irritating and annoying person who always want to know everything until l reached the bottom (self knowledge is a good thing). As long as I document this gathered information and people are interested in it I will continue to do so.

Well, now about the casting lines.

There are (on paper) 5 different types (lower) castings for (wet sump) the CB72 / 77 and C72 / 77 and the CL72 / 77, these are :

11200 259 000
11200 259 020
11200 259 030
11200 259 050 (seems to be exclusive for the CB72 / 77)
11200 259 060 (all CL72 /77 used this case, but this case is also used for CB72 / 77)

For the earlier models (dry sump) there are the following lower cases (C70, C71 and C76),

11200 250 010
11200 253 010
11200 253 020

I happen to have 6 different types (and I mean real different) lower cases for the CB72 / 77 and C72 / 77, and 3 different types lower cases for the C70, 71, 76. I'm still looking for more, because I know that there are more differences out-there then the manuals will show.

What this has to do with the lines ?, well actually nothing, but when I compared all these different types, I saw some interesting differences.

The lines only appear in the (at least which I have) more modern cases, the 11200 259 030 and on. The early cases (at least in those I have), these lines are not there. Loud Mouse, can you confirm this ?

In the three types of lower cases for the dry sump I found non of the lines.

Loud Mouse, do you happen to have a clutch cover with the small diameter oil filter cover in it ?
Could you look in one of these, and see if you find the same lines in it ?, I'm really interested in what you find.

I grabbed a clutch cover with a small diameter oil cover hole, and I didn't see any lines at all.
After your mail I looked in a more modern clutch cover (big diameter oil filter cover) and found indeed the lines you where revering too.

Could you please confirm this ?

Jensen

[LOUD MOUSE]

Do you know/understand the numbering system used by HONDA for the last 3 digits Jensen?. ......lm

Loud Mouse,

First of all thanks for your opinion about the "cracks", it confirms my presumptions.
A dear friend of my is a metallurgist, and he's always interested in such questions.

Yes I admit, I could have done that, but that would destructive research, if an expert looks to it, better leave it untouched.

I don't understand the expression "riddles your donkey", but I'm sure you meant it either positive or in a positive humorous way.

Talking in riddles is more a Dutch expression, I have to start thinking more international.

As stated in my previous mails, I am always looking for parts which differ from the standard. Add that up with my insatiable hunger for information, knowledge and mix it with perseverance and stubbornness and the result is me, an irritating and annoying person who always want to know everything until l reached the bottom (self knowledge is a good thing). As long as I document this gathered information and people are interested in it I will continue to do so.

Well, now about the casting lines.

There are (on paper) 5 different types (lower) castings for (wet sump) the CB72 / 77 and C72 / 77 and the CL72 / 77, these are :

11200 259 000
11200 259 020
11200 259 030
11200 259 050 (seems to be exclusive for the CB72 / 77)
11200 259 060 (all CL72 /77 used this case, but this case is also used for CB72 / 77)

For the earlier models (dry sump) there are the following lower cases (C70, C71 and C76),

11200 250 010
11200 253 010
11200 253 020

I happen to have 6 different types (and I mean real different) lower cases for the CB72 / 77 and C72 / 77, and 3 different types lower cases for the C70, 71, 76. I'm still looking for more, because I know that there are more differences out-there then the manuals will show.

What this has to do with the lines ?, well actually nothing, but when I compared all these different types, I saw some interesting differences.

The lines only appear in the (at least which I have) more modern cases, the 11200 259 030 and on. The early cases (at least in those I have), these lines are not there. Loud Mouse, can you confirm this ?

In the three types of lower cases for the dry sump I found non of the lines.

Loud Mouse, do you happen to have a clutch cover with the small diameter oil filter cover in it ?
Could you look in one of these, and see if you find the same lines in it ?, I'm really interested in what you find.

I grabbed a clutch cover with a small diameter oil cover hole, and I didn't see any lines at all.
After your mail I looked in a more modern clutch cover (big diameter oil filter cover) and found indeed the lines you where revering too.

Could you please confirm this ?

Jensen

[jensen]

Hi LM,

Yes, most of it, but if you have any additional information, please share it with us.
Did you check one of your early lower case's, for example one with that typical crankcase breather ?

Jensen

[LOUD MOUSE]

I suspect your part number/type of bike came from a fiche.
Am I correct.
Do ya what to know about the case without the primary chain tensioner?
I always replace those with one which has the tensioner mount locationss. .............lm

Hi LM,

Yes, most of it, but if you have any additional information, please share it with us.
Did you check one of your early lower case's, for example one with that typical crankcase breather ?

Jensen

[jensen]

Hi LM,

For the cases I have in my possession, I have the uppercases as well.
The uppercases have the engine number, and with a little help of the parts list I could track down the Honda part number of the cases.

So you're partly correct, but I used the part lists as verification, the engine numbers as input.
The conclusions written behind 11200 259-050 and 11200 259 060 are partly experience (at least for the CB72 / 77, and partly from parts lists (CL72 / 77). The conclusion implicates that ALL cl72 / 77 cases have a primary tensioner, can you confirm that from your experience with the CL72 / 77 models ?

I found that all early cases don't have the V-shaped lines in it, and not all later cases have the V-shape in it. That implicates that Honda used several production facility's or lines to mould the cases, at least for the later ones. The V-shape line is like a fingerprint for a mould.

The early cases are better moulded, the quality is higher, I also have a few engine cases of a CB92 (1959), the quality is very high, higher then the late CB72 /77. That means that Honda already started to compromise between quality and quantity.

The quality of the CB92 can be compared with the quality of the C70, C71 and C76 cases I have.
I included a picture of such an early case, take a look at it closely and compare with a later case.

Jensen

[jensen]

Loud Mouse,

Did you find the time to look at the older cases ?
What is your professional opinion ?

Jensen