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Gary does the instruction sheet tell the dealer to restamp the engine number once this mod has been accomplished ?

I looked back through the pics and saw one engine that looked like it was Dash 7.

I could not say for certain which pics showed 3 line manifolds and which were earlier. I did see some none Dash Y early 67 models with the 3 lines however.

I have to say I am still uncertain over this one.
Why the USA bikes and not the UK version ? I only know of one Dash Y bike in England, and it was re-imported by Alan in recent times.

Just went through my collection of cases, found a 68-728 casting # case with A65TA12655-Y also has the # 65 12655 stamped on the boss where the alternator support casting sits inside the primary?
Also have an odd looking case AD*****A65T with big studs and 70-9099 casting #. And boss with BSA stamps for the eng number, However this boss section is quite different to others I have seen, as are the casting parting lines, IE the patterns used to cast it are quite different to other cases I've seen. Another couple of cases which have the same 70-9099 # are made with different patterns. These have small or large studs and all have raised # boss with BSA stamps, but just the normal type.

That is my interpetation of this particular factory update kit set of instructions.



The instructions do not direct the dealer to do any stamping.



Tomorrow I will present some info from this same set of instructions that could be interpeted to include the other '67 models.

Mark has mentioned casting numbers.

Here we have some pics of two engines. The top one is a typical 1967 Dash Y engine. OK, not so true in that the alternator and points covers have been upgraded but the cases and numbers are correct. LA2720-Y.

The bottom two photos are of a 1970 Y model engine. Remember now the BSAOC UK are saying that the bikes were upgraded at the factory.

We wave the wand over the top pics and end up with the engine below.... MAGIC.

The alternator support was new for 1967 and was bolted in place. By 1970 is was cast integral with the left crankcase half.
We can compare the two halves..

Later left halves have the number pad and backstamped.
Characters stamped with the new font that appeared about Sept 1968 for the 1969 season.
Bigger crank mouth studs. (Barrel attach).
Cast alternator support.

The right half has the studs.
No gearbox bung (it was moved to the inner timing cover for the 1968 models).
Cast in oil pressure port.
Single bolt access for the timing plug.

There will be other differences also.

So the two crankcase halves of a 1970 Y bike are nothing at all like those of a 1967 model machine.
Even the numbers had to be stamped on after Aug 68. The raised pad appeared at that time... followed a month or so later by the new stamps.(New Font).

Mark also mentioned the changes to the number pad. I also have pics of that and have wondered.
It is a different casting again it seems.

I know if I post a pic I will then have to try and date them.
from memory it was early in the 1970 season.

The top two pics are of a 1970 Y Thunderbolt and then a Royal Star number from early in the 1970 season.

The different style numbering pad is certainly distinctive and not all that common. I have to imagine it was used for a short time only and may well date the Y bikes with it. From my smallish sample here I have my money on engines stamped during December and January of the 1970 season. (XD and AD prefixed).
I think they are classic pics as the bikes could just as easily be identical twins.

I would bet $10,000 that the Y Thunderbolt engine was in a batch cast and stamped in the first few months of the 1970 season. I would bet $500,000 that it was not cast and stamped in 1967 !!!!


The next pic is of a Dash X suffix bike. This time a Lightning from reasonably early in the 1967 run.
The last photo is of a set of cases from early 1969 season showing the casting numbers Mark spoke of.

That '67 number (LA 2720-Y) is the earliest -Y number I have seen to-date and have added it to my '67 number database. The previous earliest number I was aware of was HA 3252-Y.

Hi Gary, I did notice it was early and tried to read it. I could not.
It is filed under that number so we should have no reason to suspect it,- I just cannot confirm.

I will search again and see what I can come up with.

In the '67 Hornet update oiling kit instructions #6 of 12 instruction steps it reads:

"INSTALLATION OF NEW OILING KIT:

It is not neccessary to loosen engine mounting bolts.

Assemble the heavy feed and return oil lines to the new oil pipe assembly with clamps installed loosely. (DO NOT ASSEMBLE THE NEW ROCKER BOX FEED LINE AT THIS POINT.) The new oil pipe assembly with heavy line attached is inserted over the righthand exhaust pipe between the engine and frame. Oil lines are snaked over the kickstand member and upward toward the oil tank.

(Now the new rubber rocker box feed line is installed on the oil pipe assembly with hose clamp loosely fitted in place.)"

The part of this instruction segement to key in on is the underlined portion of the one sentence. Since the Hornets (most Hornets) had high pipes, then the underlined instruction would not apply, and would only apply to other models' standard street pipes. If the sentence is not a typo, then it would suggest the update oiling kit is applicable to all '67 A65/A50 models.

This must be an early one also then.

I read it as A65LA254-Y

Then there is this bike...



I have it labelled as A65LA224-Y

I guess those two numbers compliment each other. You would imagine that they both could not be wrong.

It makes the 2720-Y bike look modern.

Ok, things we know.
The Dash Y bikes are true 1967 models
(With the possible exception of the MkIV Spitfires, our hybrid bikes).
The Dash Y bikes were produced during the entire production run for that season. Or very, very close to it.
The Dash Y bikes are common.
The Dash Y bikes don't appear to be so common in the Home Market. Possibly...
The Dash Y bikes were being shipped early in the season, any dock strike delays would appear unlikely. I know of one shipped in 1966.
We know a Dash Y Spitfire was shipped to Sweden in April 1967.
Many Spitfires and Hornets have the Dash Y engine suffix.
Does that tally with the Home Market comment above ?
Lightnings and Thunderbolts also had the suffix, again in large numbers.

Gary has a document that states that all the bikes after 4144 have the improved rocker oil feed. It also says the X or Y suffix means the same.
Therefore an earlier number but with the suffix has been modified already ?

The BSAOC UK think all the above is not true, - their version is that the bikes were still at the factory until 1970 and then completely rebuilt and then exported. Ahhh Hmmm, - as 1970 models.

Hmmm, something to mull over on the cool winters nights guys.

My research of the production books indicated that machines were not dispatched in the numerical order of their frame/engine numbers. As a result, low stamped numbers were sometimes shipped later on by a month or more. So, my opinion is that the "-Y" does not include most of the '67 model year. Generally, the -Y shows up on a consistent basis beginning in the 4,000 numbers.

But the engines were stamped first, at least that is how I understand it. So a bike with 3 digits would have been made early in the season. I have been reminded that they were making 600 bikes a week at this stage.

I realise we are gaining more questions than answers but there has to be some logic amongst all this.. Doesn't there ?

Maybe so. But the "-Y" may have been added to the numbers later, especially if the engines were pre-stamped before the production line and possibly used out of numerical order.

I think 600 machines a week is a bit of a stretch. The numbers just don't add up to that kind of production unless the plant was shut down for several weeks sometime during the fall/winter/spring time period.

I see...

Thinking. hmmm

Why aren't the guys in the UK being more helpful here. As Lannis says, the guys that did all this are still about.

I have Lotus cars and went to a factory reunion at Cheshunt. The ex-workers were only too helpful in answering the various queries.

The stamping of the Dash Y suffix was before export, so done at the factory. I still can't see how these bikes never made the home market. At least they did not appear to have been common in the UK.
Why is that ?

Same with the Y bikes of 1970.... I am thinking they were all exported for a reason though.
We can let our imaginations work through that little exercise.


Have you any evidence of a Dash Y bike of 1967 being sold on the home market ?


As for the 600 bikes, it came from the BSAOC. It would include all models, Bantams etc.

The only notations in my research notes is that a majority of the TA's (Thunderbolt) were dispatched to various police and government agencies in the UK. Not many came to the states. The production books do not have any notes or markings in them regarding the "-Y" stamping that I noticed.

"their version is that the bikes were still at the factory until 1970 and then completely rebuilt and then exported. Ahhh Hmmm, - as 1970 models." Would there be a benefit to BSA? Were they taxed on bikes built in 1970, but the same tax not apply if they had some built previously, ie 1967 that they could sell? Then one could understand stamping a bunch of 1970 models as 1967 vintage and exporting them so they were not where UK persons may look and see them to be 1970 manufactured with just 1967 numbering. What is different now to 1970 is how we can put a photo up and its around the world in seconds.
It seems pretty obvious the - Y 1967 bikes had the Y to indicate they had the new oil pipes.

Welcome to the saga Mark. You have seen the crankcase halves and can see that the 1967 one is completely different to the 'AD' dated one from 1970.

You are correct about data being compared so quickly these days.
This 1970 Y bike thing has been kept under wraps for 40 years. Questions have been asked, some magazines have tried to explain it away but they have all been hoodwinked by the comments on the BSAOC website.

Alistair Cave was past President of the BSAOC and passed the story on as gospel. I have had a lengthy explanation sent to me by email just in the last week.
It is clear that even now the BSAOC committee believe their comments on the website.

I have been asking questions for ten years now and Alistair must have been aware we were on the case. It seems he remained quiet until the end..... or at least still serving up the same old story.

I am of the opinion that something happened in 1970 whereby the factory went through this charade of presenting a batch of A65LAxxxxxY bikes and maintaining that they were reworked 1967 bikes. The stories make out the bikes had been reimported back from the States or returned back from the ports. I think the reasoning being that export tax had already been paid on those machines.

The factory workers must have realised something was going on.
The Customs agents could have been deceived, - they would not know the difference.
The dealers in the US would know, and perhaps kept quiet.
The new owners would perhaps learn in due course, when the dealer supplied parts did not fit.

"The factory workers must have realised something was going on."
Maybe not many.

"The Customs agents could have been deceived, - they would not know the difference."

They would just see crates with bikes in them as described.

"The dealers in the US would know, and perhaps kept quiet."

It would just be a 1970 BSA to them, the numbers may be odd but they have the 'Y' on a raised boss so they know they are a 1970 model, its just how they came.

"The new owners would perhaps learn in due course, when the dealer supplied parts did not fit."

Maybe not a problem in 1970 or 71, BSA dealers could have be aware, like pointed out in the warranty dealer advice, but down the track, when there are no dealers just places selling BSA parts, you are going to have confusion.

If all we could find in the world were 1967 BSAs with 1967 numbers we could say this didn't happen, but there are obviously a lot of 1970 bikes with the 1967 numbers, its not like there was a crankcase and timing covers recall or something.
Someone might say 'Oh that bike must have had the C/cases replaced and stamped with it's old number's, but no one who knew BSAs would say that because the timing covers are different, the cyls and studs are different, if you replaced cases you'd do it with ones that fit.

We can probably all agree that the 1970 Y machines are 1970 in everyway but have 1967 style numbers.

Whether they were re-made '67's or not may be considered a secondary issue? If they were re-made '67's, then the factory would have spent big bucks making the change since there are so many differences. I can imagine the high cost of doing the re-make and how the factory could not have come out financially by doing that. Seems some other kind of incentive must have been in play, ie: taxes, government subsidies, etc.

Now the task seems to be getting the BSAOC UK to recognize the physical differences and that there are "Y" machines with '67 style numbers in the 1970 model year and "-Y" machines in the 1967 model year and include the information on their website.

Would there be anyone who might still face a potential liability if the true story of the 1970 A65LA*****Y BSA motorcycles came out?

If, as some of us suspect, this was an effort to avoid taxation, there may have been criminal liabilities which could carry on after the Dennis Poore/NVT deal. The 40 year charade may be there to protect more than a few reputations.

It sure would be nice to have only truthful information about the motorcycles on the BSAOC UK website. Get rid of the fiction at the very least.

Two very good posts. Thanks Gary and Two Alpha.

I have recently written on a parallel thread..

Similar thread running on Dash Y and Y bikes.

http://www.britbike.com/forums/ubbthreads.php?ubb=showflat&Number=403707&page=2

I am sure we can all see the situation. It is exactly as Gary has stated. The BSAOC website should reflect the facts.
At the moment there is no mention of either.

We have also now to consider the criminal aspects of this.
Two Alpha has mentioned liability.
Are we all party to a continuing fraud ?
If there was a cover-up just how deeply has it permeated ?

I am now starting to wonder if we have placed the BSAOC UK in a
precarious and unenviable position.

I am thinking dating of machines, the deal with DVLA and any fallout that could be possible there.
This uneasiness over the validity of their story is not news to them though. The Committee I mean.

I know I have been asking questions since 2000 and have posted on at least three forums. I am not sure when I first made contact with the guys in the UK. It was at least 6 years ago. I would have thought that was sufficient time to respond.


I have only seen a handful of dating certificates, many I did not agree with.
Some like Morgan's are okay... even if it flies in the face of the comments on their website. Others I have seen have been inaccurate (to be polite).

From my experience with BSA bikes, going back 40 years now, I have only really seen the numbers grief with the unit twins.
Perhaps the dating of those should be more methodical and be dependent on rubbings, photos and other documentary evidence rather than just a string of numbers accompanied by a cheque (check).

Correcting the website would obviously help..