Honda CB750 Sandcast

VIN and Engine Number Spread

kp · 57 · 19367

Riccardo

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Yeah, looked shit on the Kwaker mock up but I have to confess that I loved the pipes on the Rocket 3. One thing the Brits did well with their bikes was design. That Rocket 3 was such a nice machine to look at as was the Commando
How did this thread get hijacked by this trivia

hi jacking by hi yakkin.  i be settin bad example.  picture of my 1974 Mk.II



Steve.....GREAT Commando!!!!,
Riccardo
Your Italian friend.
737/940 Restored
1081/1362 Preserved
1256/665 Restored - ex Owner: Chris R.
10253/10315 (K0) Next project
1969 - Kawasaki H1 Mach III low ign cover - Restored
1969 - Kawasaki H1 Mach III high ign cover - Restored
1971 - Kawasaki H1A - Restored
1973 - Kawasaki H1D - Preserved
1973 - Kawasaki Z1 Blackhead - Restored
1971 - Norton Commando SS - Preserved
1978 - Honda CBX - Unmolested Museum Quality
1988 - Honda CB 400SS - Unmolested
1997 - BMW R80 GS Basic - blue frame - Museum Quality
2007 - BMW HP2 Megamoto - blue frame - New


Riccardo

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The Vin/Engine spread is an old story for many of us.

It's a drill into our brains.

In this forum we found a lot of answers to all of our doubts and questions that perhaps do not even put the designers of this bike that we love.

Yet we always return to the same question mark.

In 2008 I bought a sandcast by Chris, the 1256 / E665, a bike with a big spread.

Yet the engine was never out of that frame.

After some time Chris contacted me and told me that this was the right engine of the motorcycle.

That probably there is a matching list of Numbers that someone owns and perhaps has no interest in disclosing it.

We certainly our bikes have a unique feature, the engines can not be cloned, which in the world of collecting is done quite often and this is an irrefutable fact.

So I believe the spread is something quite natural and that occurred probably due to organizational reasons at a time when there was a growing interest in the market and that, probably, sent into a tailspin a major corporation such as Honda.

Riccardo
Riccardo
Your Italian friend.
737/940 Restored
1081/1362 Preserved
1256/665 Restored - ex Owner: Chris R.
10253/10315 (K0) Next project
1969 - Kawasaki H1 Mach III low ign cover - Restored
1969 - Kawasaki H1 Mach III high ign cover - Restored
1971 - Kawasaki H1A - Restored
1973 - Kawasaki H1D - Preserved
1973 - Kawasaki Z1 Blackhead - Restored
1971 - Norton Commando SS - Preserved
1978 - Honda CBX - Unmolested Museum Quality
1988 - Honda CB 400SS - Unmolested
1997 - BMW R80 GS Basic - blue frame - Museum Quality
2007 - BMW HP2 Megamoto - blue frame - New


DW69K0

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I have debated posting this information, but I really think I have uncovered a new Sandcast breakthrough or this will open up some new thoughts on how Frame and Engine Vin's were paired.

The skeptics will say this cannot happen, but bare with me with an open mind please.

To date, the current Vin Directory has four Frame and Engine Vin paired with a delta of 1. Two have 1 digit higher Engine number stamping sand two that are 1 digit lower, but nonetheless, four are paired within one number. I hear that a Sandcast exists that has matching numbers, but it is not listed in the Vin Directory.

Here comes the controversy, Steve was asking what the highest recorded  Frame/Engine mismatch? Well, I purchased a Sandcast last summer with Frame 3223 and E1685 which is - 1538 from the frame. The bike has the original owner history. This Sandcast got me interested in the Vin ranges as I tried to figure out how this might happen. Being curious, I have dug deep into the Frame and Engine pairings trying to figure this bike out. Here is the interesting and intriguing part of my discovery. The top engine casting date on E1685 is June 23 (6-23).

The top casting date falls in line with the the frame Vin date, which seems to me, the Engines were stamped close to the same time it was placed in the frame, or Honda re-stamped 1685, as it clearly falls outside any normal range distribution in the Vin Directory. Here are the Sandcasts I own that are produced before and after 3223 with top casting dates before and after June 23, but still falling in the month of June.

3043/2765 - 6-13 thin lip 9 hole clutch cover
3223/1685 - 6-23  blue engine dot - original unmolested Sandcast (rare)
4089/3599 - 6-24 right hand horn

The top casting date is in line with the Frame Vin ranges, but Engine number is clearly not in normal or expected ranges. The engine of E1685 has a blue dot on the top casing. Could the dots really indicate an issue with an engine???

I am now very curious if other known original pairings contain engine dots with higher than "normal" mis-pairings.  Is this the reason for the engine dots?.  Ricardo or Chris, does 1256/E665 have an engine dot on it?

3223/E1685 is all original not having any restoration work and is in original factory assembled condition. This bike did have a windshield on it (removed), grips replaced, tires replaced, battery replaced, oil filter housing replaced, and chain replaced. but other than those mentioned items is a factory original bike.

We need more top casting dates to be published to get more information on this topic.

Attached is the Engine Number stamping.

Best,
Duane
« Last Edit: April 25, 2016, 06:13:46 pm by DW69K0 »


Steve Swan

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I have debated posting this information, but I really think I have uncovered a new Sandcast breakthrough or this will open up some new thoughts on how Frame and Engine Vin's were paired.

The skeptics will say this cannot happen, but bare with me with an open mind please.

To date, the current Vin Directory has four Frame and Engine Vin paired with a delta of 1. Two have 1 digit higher Engine number stamping sand two that are 1 digit lower, but nonetheless, four are paired within one number. I hear that a Sandcast exists that has matching numbers, but it is not listed in the Vin Directory.

Here comes the controversy, Steve was asking what the highest recorded  Frame/Engine mismatch? Well, I purchased a Sandcast last summer with Frame 3223 and E1685 which is - 1538 from the frame. The bike has the original owner history. This Sandcast got me interested in the Vin ranges as I tried to figure out how this might happen. Being curious, I have dug deep into the Frame and Engine pairings trying to figure this bike out. Here is the interesting and intriguing part of my discovery. The top engine casting date on E1685 is June 23 (6-23).

The top casting date falls in line with the the frame Vin date, which seems to me, the Engines were stamped close to the same time it was placed in the frame, or Honda re-stamped 1685, as it clearly falls outside any normal range distribution in the Vin Directory. Here are the Sandcasts I own that are produced before and after 3223 with top casting dates before and after June 23, but still falling in the month of June.

3043/2765 - 6-13 thin lip 9 hole clutch cover
3223/1685 - 6-23  blue engine dot - original unmolested Sandcast (rare)
4089/3599 - 6-24 right hand horn

The top casting date is in line with the Frame Vin ranges, but Engine number is clearly not in normal or expected ranges. The engine of E1685 has a blue dot on the top casing. Could the dots really indicate an issue with an engine???

I am now very curious if other known original pairings contain engine dots with higher than "normal" mis-pairings.  Is this the reason for the engine dots?.  Ricardo or Chris, does 1256/E665 have an engine dot on it?

3223/E1685 is all original not having any restoration work and is in original factory assembled condition. This bike did have a windshield on it (removed), grips replaced, tires replaced, battery replaced, oil filter housing replaced, and chain replaced. but other than those mentioned items is a factory original bike.

We need more top casting dates to be published to get more information on this topic.

Attached is the Engine Number stamping.

Best,
Duane


Duane, i think you may very well be on to something.  Great inference and deduction.  Yours is one of the reasons i requested casting dates.  I hope members send them in.  Interesting how early production cases do not have casting dates.


kp

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Very interesting thoughts.
I think that cases were stamped prior to engine assembly but post machining as they have stamped letter/numbers on the rear of each half that obviously signify pair matching after line boring/machining etc. E numbers could also be undertake post assembly also but I believe stamping would have been much easier with a bare case than a completed engine. Just a thought. Case halves do not necessarily get cast on the same day.
One thing that does intrigue me is the different engine number pads. All early pads (the ones we have records of) are the narrow type. Changes to a wider pad started occurring around E 600 or so (894 and 958 are wider pads) but there are some engines where the narrow pad is seen on cases over E1100 I can't recall the number but thought it was Chris' E1106. Marty, does E664 have a wide pad
KP
Yabba Dabba KP


4pots1969

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I tear me to understand the meaning of the text...???
But I'll try to answer what I think I understand ...
Duane, but why add a blue or red sticker on the engine? To say what? and to whom?  Why use two colors to only report a problem?  the red warned what? the blue warned what?
We can also assume that initially all motorcycles coming out of the assembly lines receive a blue or red sticker for any other reason?  
I just try to understand ...
« Last Edit: April 26, 2016, 09:15:49 am by 4pots1969 »


DW69K0

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Gerald,

I think the dot might be present on engines that had an issue or might represent an issue once assembled. Frame 3223 would have been assembled in June, but all other 16xx engines have May cast dates on the top of the engine. I believe something happened in assembly with E1685. Thus the blue dot.

E1685 should theoretically have a May top casting date (around May 20th) but was clearly cast in June. If falls far outside the normal population distribution.

           E10xx-E21xx all have May stamped top engine casting dates.

           E22xx-36xx have June top casting dates.

I have identified 5 other Engine casting dates that fall outside the normal distribution. I plan to reach out individually to these owners to see if the top of the engine contains a blue dot as these owners may not what to be called out on db.

Let me know if you need me to structure my sentences differently for translations.

Best,
Duane


4pots1969

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Gerald,

I think the dot might be present on engines that had an issue or might represent an issue once assembled. Frame 3223 would have been assembled in June, but all other 16xx engines have May cast dates on the top of the engine. I believe something happened in assembly with E1685. Thus the blue dot.

E1685 should theoretically have a May top casting date (around May 20th) but was clearly cast in June. If falls far outside the normal population distribution.

           E10xx-E21xx all have May stamped top engine casting dates.

           E22xx-36xx have June top casting dates.

I have identified 5 other Engine casting dates that fall outside the normal distribution. I plan to reach out individually to these owners to see if the top of the engine contains a blue dot as these owners may not what to be called out on db.

Let me know if you need me to structure my sentences differently for translations.

Best,
Duane

Let me know if you need me to structure my sentences differently for translations.  Thanks for that !!

How do you explain the blue dot of the VIN 97 E-100 to our friend Mark?
And the red dots, you explain the how? Why as red dots?
Why use two colors to only report a problem???
Thanks,
Gerard (without L) ;)
« Last Edit: April 26, 2016, 09:11:18 am by 4pots1969 »


Steve Swan

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i believe Duane is raising some very good observations.  particularly with 1685 having a June casting date.  and the rest of what he said. and the fact he has reached out to the 5 owners with vin/casting number outliers will be interesting what he discovers.

i believe Gerard is asking some strong questions, but difficult to truly, if ever, find an answer.  and i "see" Gerard's logic.  "why 2 colors to only report a problem?"

the above dialog is excellent.  this is exactly how the scientific method challenges theory or how archeologists challenge what they believe about there findings.  we sandcast enthusiasts ARE archeologists of a sort.

i still think Duane's study is necessary, if not solid and could lead us to support our theory or further postulate what we "think" happened at the factory.  another and a more difficult approach would be to take all cases with dots and inspect the inside and outside of cases for any factory corrections, repairs.  we know the factory modified and repaired cases, because we have visualized modifications and repairs that could have happened ONLY at the factory.

i wonder if Emi Oye of Yamiya knows anyone who worked at factory who knows about the dots.  for us sandcast folk, those dots are called "sandcast UFO's."  ??? ??? ??? ???


DW69K0

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First off...my apologies for the bad spelling on the name Gerard!!!

I run a large production line for a living, and we have different ways to mark issues that happen in production to address some rework issues we tag certain problems, so this is why I was asking about the dots or Sandcast UFOs....as Steve now calls them  ;D

From what I've read on the db, the dots do not correlate to the body set colors. Mark's 97/E100 is a good example of that as the original 19L tank was red,  so the dots had to have another meaning during assembly.

The real enlighten and discovery moment for me, was the engine's number on 3223/E1685 being cast in June and the rest of the engines with June top casting date being much higher (E21xx-36xx).

This still leads me to believe the engines were stamped at a point when they were close to being assembled in the frames and this theory goes against prior assumptions.

Best,
Duane


4pots1969

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Duane for me, you were already apologized... ;)

« Last Edit: April 26, 2016, 11:07:31 am by 4pots1969 »


cb7504

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KP engine number 664 has a small vin pad as does 181. Marty K.


hondasan

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E1106 has a small VIN pad, and appears to be quite a high engine number for a small pad. The casting date is 4/23 which (based on the limited number of other casting date records) seems to be a little earlier than other similar large pad engine numbers. Maybe indeed this one was held back a while before stamping of the number. That said, it is in frame 1120, so a really close "match" in that respect?

Chris R.
Chris R.
302/338


DW69K0

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Chris,

Any evidence that this engine had a blue or red dot placed close to the top casting date?

Thanks much,
Duane


DW69K0

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I think the small vin pad on Chris' E1106 with it being a higher E number, could also possibly support the theory that the engines were stamped close to same time as the Fame Vin.
DW