BritBike Forum logo
BritBike Sponsor BritBike Sponsor
BritBike Sponsor BritBike Sponsor
BritBike Sponsor BritBike Sponsor
BritBike Sponsor BritBike Sponsor
The Bonneville Shop BritBike Sponsor
Home | Sponsors, Newsletter | Regalia | Calendar | Bike Project | BritBike Museum
| Spiders Cartoons, | DVD- Manuals & Parts books
Upgrade to: Premium Membership | Premium Life Membership | Vendor Membership | Site Sponsor Membership
Google advert
ShoutChat Box
Buy BritBike staff a coffee
Buy BritBike's staff a coffeeStill here since 1996 serving BritBike enthusiasts..
Search eBay for motorcycle parts in following countries
Australia, Canada, France, Holland, Italy, United Kingdom, USA
Random Gallery photo
Member Spotlight
Peter Quick
Peter Quick
Jaffrey, NH, USA
Posts: 867
Joined: June 2002
Show All Member Profiles 
Newest Members
Bill Davis, DGreear, KevKav, Joe B, tobbe53
10732 Registered Users
Top Posters(30 Days)
franko 121
DavidP 62
Rohan 54
reverb 50
Popular Topics(Views)
920,952 mail-order LSR
Forum Statistics
Forums34
Topics67,121
Posts672,764
Members10,732
Most Online14,755
May 5th, 2019
Who's Online Now
57 registered members (Adam M.), 502 guests, and 853 spiders.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
Page 1 of 2 1 2
BSA Engine Number #417193
02/05/12 8:45 pm
02/05/12 8:45 pm
Joined: Oct 2010
Posts: 31
Illinois, USA
M
MotoMike Offline OP
BritBike Forum member
MotoMike  Offline OP
BritBike Forum member
M

Joined: Oct 2010
Posts: 31
Illinois, USA
Have a engine I was wondering about....the number reads as follows...A65TA 1900XD...I guess it is a 1967 but what is with the XD?

Support Your #1 BritBike Forum!

Check out British motorcycles for sale:
British Motorcycles on e-Bay UK, British motorcycles on e-Bay North America


Re: BSA Engine Number [Re: ] #417231
02/06/12 12:51 am
02/06/12 12:51 am
Joined: Oct 2008
Posts: 1,666
Canada
L
LarryLebel Online content
BritBike Forum member
LarryLebel  Online Content
BritBike Forum member
L

Joined: Oct 2008
Posts: 1,666
Canada
XD = Dec. 1969

Re: BSA Engine Number [Re: MotoMike] #417237
02/06/12 1:21 am
02/06/12 1:21 am
Joined: Aug 2001
Posts: 1,733
Christchurch, NZ
Kevin (NZ). Offline
BritBike Forum member
Kevin (NZ).  Offline
BritBike Forum member

Joined: Aug 2001
Posts: 1,733
Christchurch, NZ
I don't think the XD is anything to do with the later coding system introduced during the 1969 season.

The Month/Year codes were always as a prefix.. from what we have been seeing so far it is only the 'Y' and 'X' bikes that had a suffix code.

I am pretty sure this is going to be a 1967 model engine.
It will be an interesting photo. As I see it at the moment all three portions of the S/N are contradictory.
A photo should be able to date the engine in itself, without reference to any markings.

This is going to be an interesting one.
The serial number itself would normally be considered too low in the model year to have earned a suffix.



Why, Y, Dash Y..



Re: BSA Engine Number [Re: MotoMike] #417408
02/07/12 4:12 am
02/07/12 4:12 am
Joined: Aug 2001
Posts: 1,733
Christchurch, NZ
Kevin (NZ). Offline
BritBike Forum member
Kevin (NZ).  Offline
BritBike Forum member

Joined: Aug 2001
Posts: 1,733
Christchurch, NZ
Another possibility is that it is a 1970 Thunderbolt engine and someone has modified the Y suffix to read XD.

That would make a lot of sense and remove some of the possible confusion the number would have otherwise generated.



If this is the engine then I doubt the factory would have been involved in the stamping... the 'Y' engines had been in production for many months by December (about 6 months).

As Larry has suggested, the XD could be taken as Dec 1969 for a 1970 engine and at least then you would be buying the correct parts for it.

All 1970 model A65 engines, apart from the 'Y' models, had five digit serial numbers.

Last edited by Kevin (NZ).; 03/12/13 11:33 am.

Why, Y, Dash Y..



Re: BSA Engine Number [Re: Kevin (NZ).] #417588
02/08/12 2:29 pm
02/08/12 2:29 pm
Joined: Oct 2010
Posts: 31
Illinois, USA
M
MotoMike Offline OP
BritBike Forum member
MotoMike  Offline OP
BritBike Forum member
M

Joined: Oct 2010
Posts: 31
Illinois, USA
here is a picture....

[Linked Image]

Re: BSA Engine Number [Re: MotoMike] #417603
02/08/12 3:45 pm
02/08/12 3:45 pm
Joined: Oct 2001
Posts: 537
Norway
Ola Offline
BritBike Forum member
Ola  Offline
BritBike Forum member

Joined: Oct 2001
Posts: 537
Norway
Oh no...


There are no bosses in a technical discussion
(Doug Hele, 1919 - 2001)
Re: BSA Engine Number [Re: Ola] #417611
02/08/12 4:44 pm
02/08/12 4:44 pm
Joined: Oct 2010
Posts: 31
Illinois, USA
M
MotoMike Offline OP
BritBike Forum member
MotoMike  Offline OP
BritBike Forum member
M

Joined: Oct 2010
Posts: 31
Illinois, USA
yeah I was kinda thinking the same thing...

Re: BSA Engine Number [Re: MotoMike] #417614
02/08/12 4:51 pm
02/08/12 4:51 pm
Joined: Apr 2011
Posts: 600
North Coast, BC, Canada
Two Alpha Offline

Life member
Two Alpha  Offline

Life member

Joined: Apr 2011
Posts: 600
North Coast, BC, Canada
Oh yes! Great picture of a very interesting serial number.

Definitely not 1967.
Any chance you have the frame with a matching number?

Kevin had a picture of an engine with a similar case style, A65TA 12215Y.
The bike with your engine coming off the line in December of 1969 as a 1970 model does make sense based on the case style.
The 1900 number is odd, at that point in time it would normally be represented as 01900.
Seems like the guy doing the stampings may have gotten momentarily confused as to whether this one was to be a 1970, or a 1970 with a number that made it look like it was a 1967.
I'm looking forward to reading Kevin's take on this one.

Last edited by Two Alpha; 02/08/12 5:21 pm. Reason: tweeked a little

BSA
Matchless
Triumph
Re: BSA Engine Number [Re: Two Alpha] #417619
02/08/12 5:19 pm
02/08/12 5:19 pm
Joined: Feb 2003
Posts: 2,818
Ohio
R
Rickman Offline
BritBike Forum member
Rickman  Offline
BritBike Forum member
R

Joined: Feb 2003
Posts: 2,818
Ohio
Here is a thought:

Perhaps, JUST perhaps, these may be a set of replacement cases???

They are certainly later cases with that boss and BSA imprints, but the numbering sure looks to be '67...

Re: BSA Engine Number [Re: Rickman] #417621
02/08/12 5:25 pm
02/08/12 5:25 pm
Joined: Apr 2011
Posts: 600
North Coast, BC, Canada
Two Alpha Offline

Life member
Two Alpha  Offline

Life member

Joined: Apr 2011
Posts: 600
North Coast, BC, Canada
That's possible, but a little unlikely. This style of case was only produced for a very short time, maybe only weeks, before it was replaced with an improved version.


BSA
Matchless
Triumph
Re: BSA Engine Number [Re: MotoMike] #417644
02/08/12 6:57 pm
02/08/12 6:57 pm
Joined: Aug 2001
Posts: 4,521
argyll. scotland, uk
gavin eisler Offline
BritBike Forum member
gavin eisler  Offline
BritBike Forum member

Joined: Aug 2001
Posts: 4,521
argyll. scotland, uk
Looks like 1970 barrels to me, thick flange. Does the clutch cable enter vertically or horizontally? What front brake is fitted, SLS or TLS.
after looking hard at the number and looking at the Bacon book.
A65 TA is weird, the T should represent the Thunderbolt model and the A suggest 67 , I think the A is a mistake or some other designation like a forces model or something, the XD is December 1970 by my reckoning, that fits with the embossed number area and the 1970 thick barrels. I hate to see red hermish3te on the joints, its hard to get off, paint stripper we call Nitromors in the UK I think you call it Naval jelly, will shift it, you know the stuff, it stinks and burns your skin.

Last edited by gavin eisler; 02/08/12 7:10 pm. Reason: idle conjecture

71 Devimead A65 750
56 Norbsa 68 Longstroke A65
Cagiva Raptor 650
MZ TS 250
The poster formerly known as Pod
Re: BSA Engine Number [Re: MotoMike] #417660
02/08/12 8:24 pm
02/08/12 8:24 pm
Joined: Aug 2001
Posts: 1,733
Christchurch, NZ
Kevin (NZ). Offline
BritBike Forum member
Kevin (NZ).  Offline
BritBike Forum member

Joined: Aug 2001
Posts: 1,733
Christchurch, NZ
[Linked Image]



****EDIT****
Photo being reposted to show exactly the situation.
****


Woweee, what an amazing photograph..

Brilliant. Thanks for posting.

We have never seen anything like this before and it really does make a lot of sense.

We can tell by looking at the engine and the casting boss that it is a 1970 model engine and identical to those we have seen produced or stamped over that Xmas period of 1969.

I think we managed to deduce that from the normal and 'Y' bikes that we have seen. John gave an example of a 'Y' bike of this era. As he mentioned also, - the unusual shaped engine number pad was only cast like that for a few weeks.

Is there a frame that matches this engine ?

From what I am seeing it is a Y bike of Dec 1970 season that the guy stamping the engine has got confused with.
We can see from the castings, the engine itself, from the font and from the backstamping that the engine is all 1970.
It only has the four digits which makes it unusual.

We have never seen a Y bike leading the S/N sequence with a zero. Many of the normal sequence did which was an identifier for the 1970 year, ie they all had 5 digits so started with a 0 or a 1.

I am pretty sure we have seen a Y bike with 4 digits before though.

Wow, if ever we needed a missing link to tie the Y bike A65TA sequence to 1970 then this would be it.

The poor guy stamping the engines was used to doing one of two styles.... with this one he must have just lost himself. What other explanation could there be for it ?

Rather than picking up the 'Y' stamp he picked up the X and D stamps that he had been using all day.

That is certainly one out of the box... it would be interesting to see how they recorded that one in the despatch books.
I am 100% sure it was made, and stamped, within weeks of Xmas 1969 as a 1970 model machine.




Last edited by Kevin (NZ).; 03/12/13 11:35 am.

Why, Y, Dash Y..



Re: BSA Engine Number [Re: MotoMike] #417686
02/09/12 12:28 am
02/09/12 12:28 am
Joined: Oct 2010
Posts: 31
Illinois, USA
M
MotoMike Offline OP
BritBike Forum member
MotoMike  Offline OP
BritBike Forum member
M

Joined: Oct 2010
Posts: 31
Illinois, USA
Amazing the amount of good info this forum has....I wish I could help more...I do not have a frame with the engine, got it with a pile of parts....now the question, what do do with it!

Re: BSA Engine Number [Re: MotoMike] #417694
02/09/12 2:05 am
02/09/12 2:05 am
Joined: Aug 2001
Posts: 1,733
Christchurch, NZ
Kevin (NZ). Offline
BritBike Forum member
Kevin (NZ).  Offline
BritBike Forum member

Joined: Aug 2001
Posts: 1,733
Christchurch, NZ
Quote
....now the question, what do do with it!


I know it is a good engine and deserves to be in a bike, but,-
.....

You can see how excited we have been to have seen it. I think a few of the guys here own 1970 bikes with a strange numbering sequence.
You may have read a few threads here already.

The thing is that until the last few years we just lived with the confusion, generated in part by websites such as the BSAOC UK and even indeed the dating info on our own site here.
Now, in the past year or so the guys have ganged up and yelled ENOUGH.
Let's get this sorted out.
In November Gary E helped us get a conclusion to the 1967 Dash Y issue many of us had been wondering about.

In the process we also made huge advances in obtaining a clearer picture on the Y bikes of 1970.
We now accept that the Y bikes of 1970 were made and we have a fair idea of the numbers. My guess is that possibly 10% of the 1970 A65 twins were stamped in a similar style to yours.

But all the others are stamped in a purely 1967 style sequence.... nothing about the number would lead the un-initiated to think they were anything but 1967.

Now we have one.... your engine !
One that is literally a missing link.

I believe it is a stamping error but to me everything falls into place.
We knew the date when that strange number casting was used. The sample pool was large enough plus we had a dating certificate I believe. Anyway it was only ever used on XD, a few AD and a number of A65TA*****Y and A65LA*****Y bikes.
Xmas/New Year of the 1970 model run.

Hahahha, I am wondering if this was a 'morning after' stamping job.
I would not be at all surprised.
The guy that did it may still be about 42 years after the event. He should remember doing it, I think he would have had to explain himself and would have been party to the discussion as to what they were going to do with the engine.

There may be another possibility also. Hard to envisage one though, perhaps along the lines of a Special Order for some customer.
What it has done is draw attention to the fact that the 1967 style A65TA code has been linked to the 1970 styled XD date system. It is all there to see and on just the one engine.

Until we crack the rest of the puzzle this remains unique and very much like a museum piece.
I am guessing someone like John or Bruce will be tempted to make you an offer for it.

[Linked Image]

Here is a pic of what a 'normal' twin would look like made that month.
Some points of interest. The XD is the prefix and the 4 digit number has the zero incorporated. You will note the distinctive casting also....it literally just seemed to have appeared for a few weeks production before it was revised.

Last edited by Kevin (NZ).; 02/09/12 5:26 am. Reason: 1970 XD pic added.

Why, Y, Dash Y..



Re: BSA Engine Number [Re: MotoMike] #417718
02/09/12 8:54 am
02/09/12 8:54 am
Joined: Aug 2001
Posts: 1,733
Christchurch, NZ
Kevin (NZ). Offline
BritBike Forum member
Kevin (NZ).  Offline
BritBike Forum member

Joined: Aug 2001
Posts: 1,733
Christchurch, NZ
[Linked Image]

Sorry about the quality but this is a Y bike of the same era.


Why, Y, Dash Y..



Re: BSA Engine Number [Re: Kevin (NZ).] #417744
02/09/12 4:42 pm
02/09/12 4:42 pm
Joined: Apr 2011
Posts: 600
North Coast, BC, Canada
Two Alpha Offline

Life member
Two Alpha  Offline

Life member

Joined: Apr 2011
Posts: 600
North Coast, BC, Canada
That one is A65 TA 12215 Y.

Here's one more with the same style case, according to the seller it is AD 04670 A65L.

[Linked Image]



BSA
Matchless
Triumph
Re: BSA Engine Number [Re: MotoMike] #417748
02/09/12 4:57 pm
02/09/12 4:57 pm
Joined: Sep 2002
Posts: 7,728
Seattle
Alex Offline

BritBike Forum member
Alex  Offline

BritBike Forum member

Joined: Sep 2002
Posts: 7,728
Seattle
As I understand it, at some point in 1970, BSA started putting the model designation (A65L, A65T) on the engine as the suffix while maintaining it as the prefix on the frame. The date code, however, stayed in front of the serial number.


A smattering:
'53 Gold Flash
'67 Royal Star
'71 Rickman Metisse
'40 Silver Star
'37 Rudge Special
sixtyseventy Lightboltrocket road racer...and many more.
Re: BSA Engine Number [Re: Alex] #417761
02/09/12 7:20 pm
02/09/12 7:20 pm
Joined: Apr 2011
Posts: 600
North Coast, BC, Canada
Two Alpha Offline

Life member
Two Alpha  Offline

Life member

Joined: Apr 2011
Posts: 600
North Coast, BC, Canada
The lowest number I've got, with the model designation as the suffix, is ND 02489 A65L. That bike would have come off the end of the line in October of 1969, more than a full month before MotoMikes.

A fair portion of the then current method was out the window when it came to MotoMike's engine. The usual method would be for the number portion to be stamped on the engine as it was completed, model and date to follow when the engine was mated with a chassis. You would also expect that they would have added the A65L, A65T, A65F, or A50 at the time the engine was completed.

All of the numbers at that point in time should have been five digits, only four digits on the MotoMike engine must have just added to the confusion.

Perhaps the guy doing the stamping started off with adding the "A" to fit the 1967 style (A65TA) then maybe realized that the number didn't match (all the 1970 Y bikes have five digit numbers), and capped it off with the date code (XD) at the end as the final coupe de grace/repair of a botched job.

edit: I had forgotten here that there were a few four digit 1970 "Y" bikes, in the 7000 range, that they must have missed when doing the 1969 "Y" bikes.

Last edited by Two Alpha; 02/01/14 1:57 pm.

BSA
Matchless
Triumph
Re: BSA Engine Number [Re: MotoMike] #417767
02/09/12 7:56 pm
02/09/12 7:56 pm
Joined: Jan 2012
Posts: 324
florida
L
LeonGustus Offline
BritBike Forum member
LeonGustus  Offline
BritBike Forum member
L

Joined: Jan 2012
Posts: 324
florida
Would an A50R fit in this conversation? Two Alpha - my engine is stamped ND 02116 A50R all in a row on the background stamped boss. The frame# boss is stamped ND 02116 A50R with the A50R below but still on the boss.


October of 69-A50R
Re: BSA Engine Number [Re: Two Alpha] #417768
02/09/12 7:57 pm
02/09/12 7:57 pm
Joined: Aug 2001
Posts: 1,733
Christchurch, NZ
Kevin (NZ). Offline
BritBike Forum member
Kevin (NZ).  Offline
BritBike Forum member

Joined: Aug 2001
Posts: 1,733
Christchurch, NZ
Quote
(all the 1970 Y bikes have five digit numbers),


I don't think that is the case.
All the normal 1970 serial numbers have the 5 digits for the 1970 season. This was achieved by placing a zero at the start of the number if required.

I have a couple of 4 digit Y bikes listed here.
I will see if I can dig up the numbers.
7879 is one, 7031 another. (Edited.. added 7867)
I am guessing it was because they were either picking up numbers, - or spare numbers.. from the 1967 despatch books.

The 1900 number is really unusual as you suggest though John.
It is very low if they were using the 1967 books as a guide.

I thought you may have been tempted to add the engine to your collection.

Last edited by Kevin (NZ).; 02/10/12 4:30 am. Reason: Added 7867
Re: BSA Engine Number [Re: Two Alpha] #417783
02/09/12 9:35 pm
02/09/12 9:35 pm
Joined: Oct 2001
Posts: 537
Norway
Ola Offline
BritBike Forum member
Ola  Offline
BritBike Forum member

Joined: Oct 2001
Posts: 537
Norway
[Linked Image]


There are no bosses in a technical discussion
(Doug Hele, 1919 - 2001)
Re: BSA Engine Number [Re: MotoMike] #417789
02/09/12 9:57 pm
02/09/12 9:57 pm
Joined: Aug 2001
Posts: 1,733
Christchurch, NZ
Kevin (NZ). Offline
BritBike Forum member
Kevin (NZ).  Offline
BritBike Forum member

Joined: Aug 2001
Posts: 1,733
Christchurch, NZ
Hi Ola, yes that is a normal 1970 bike.
The Y bikes of 1970 used a completely different number sequence. Actually almost random in nature but it did have an affinity to big numbers, 11000 to 15000 or so.

The normal 1970 bikes were recorded in the 1970 shipping books.

On the other hand, the 1970 Y bikes had all their details recorded in the 1967 books (I know, don't ask us why)...
Because they were literally squeezed into the 1967 records we are still unsure whether they used vacant numbers, numbers of bikes that never existed, - or if there was a chance of a duplicated number. ie a Dash Y bike of 1967 sharing the same number as a Y bike of 1970.

The first Dash Y bikes started around 3000 in the 1967 year. Until now I am not so sure we had seen a number lower than that in the 1970 Y bike sequence. I think the two 7000 ones were the best I could come up with.

If you look at the dating lists for 1970 (normal) bikes it will say they started at 101. That is impossible as they were all 5 digits.

But you are correct, Mike's engine number is unique in more ways than one. Very unusual.

Because BSA were using two sets of books for the 1970 twin production it must have produced a few dilemmas along the way.

Which book did they record Mike's engine in for example ?

It would stand out like the proverbial if they recorded it in the 1967 records... likewise it would draw attention if it was entered in the 1970 books.

I actually doubt it was recorded anywhere. The numbers really are that damning.

Sorry Ola, I have just realised you may have been helping Leon, Alex and John out with their query.
I think Leon's number is typical. Alex has a good point about the change in style... I had been ignoring or overlooking that.

Last edited by Kevin (NZ).; 02/09/12 10:17 pm. Reason: Last paragraph added

Why, Y, Dash Y..



Re: BSA Engine Number [Re: LeonGustus] #417792
02/09/12 10:16 pm
02/09/12 10:16 pm
Joined: Apr 2011
Posts: 600
North Coast, BC, Canada
Two Alpha Offline

Life member
Two Alpha  Offline

Life member

Joined: Apr 2011
Posts: 600
North Coast, BC, Canada
Originally Posted by LeonGustus
Would an A50R fit in this conversation? Two Alpha - my engine is stamped ND 02116 A50R all in a row on the background stamped boss. The frame# boss is stamped ND 02116 A50R with the A50R below but still on the boss.


Sure does, yours would have also came off the line in October, 2009.

Any chance of posting a photo of the engine serial number? Of course other photos of the bike would be a treat as well.


BSA
Matchless
Triumph
Re: BSA Engine Number [Re: Kevin (NZ).] #417795
02/09/12 10:33 pm
02/09/12 10:33 pm
Joined: Apr 2011
Posts: 600
North Coast, BC, Canada
Two Alpha Offline

Life member
Two Alpha  Offline

Life member

Joined: Apr 2011
Posts: 600
North Coast, BC, Canada
Originally Posted by Kevin (NZ).
Quote
(all the 1970 Y bikes have five digit numbers),


I don't think that is the case.
All the normal 1970 serial numbers have the 5 digits for the 1970 season. This was achieved by placing a zero at the start of the number if required.

I have a couple of 4 digit Y bikes listed here.
I will see if I can dig up the numbers.
7879 is one,7031 another.


I've got a few 1969's listed with only 4 digits, all of the 1970's are 5 digits starting with 0 or 1.

Originally Posted by Kevin (NZ).

I thought you may have been tempted to add the engine to your collection.


Well, you must know that it wouldn't take much of a hint to get me at least thinking about it. I'm a long way from Illinois so the freight costs alone would take some serious consideration. It is a very interesting serial number though!


BSA
Matchless
Triumph
Re: BSA Engine Number [Re: Ola] #417799
02/09/12 10:36 pm
02/09/12 10:36 pm
Joined: Apr 2011
Posts: 600
North Coast, BC, Canada
Two Alpha Offline

Life member
Two Alpha  Offline

Life member

Joined: Apr 2011
Posts: 600
North Coast, BC, Canada
Nice one Ola, that's the earliest number I've seen with the model designation as the suffix. Off the line in August, 1969.


BSA
Matchless
Triumph
Page 1 of 2 1 2

Moderated by  Allan Gill, Jon W. Whitley 

Home | Sponsors | Newsletter | Regalia | Calendar | Bike Project | BritBike Museum | Spiders Cartoons | DVD- Manuals & Parts books
Upgrade to: Premium Membership | Premium Life Membership | Vendor Membership | Site Sponsor Membership


Powered by UBB.threads™ PHP Forum Software 7.7.1