[KillSwitch]

I have a 1967 BSA hornet motor and frame, the motor serial # ends with a -Y but the frame doesn't. The title has the Y also. Does any body have any idea why this is? I need to have the bike inspected at the DMV since the title is from Colorado and I live in Kansas. I'd like to have an answer for the inspector if he questions it. Thanks

 

[beaverbikes]

There are stories and arguments about the Y and -Y bikes. Different theories between Y and -Y, but they get confused and intermingled. And nobody alive today seems to remember what its all about. -Y on 67 Hornets is very common, I have one myself. My best understanding is that the warranty coverage was changed for a lot of 67 engines, due to some earlier problems. All engines to get the newer warranty scheme got the -Y stamped. Shouldn't matter to the Kansas DMV, VIN should be the frame number. More or less.

 

[Tony the torch]

On a lot of mid 60's BSA the model designations don't match, many had A50 frames and A65 engines although the numbers were the same, so technically the engine and frame numbers don't match.

 

[beaverbikes]

They started matching the numbers during the 66 run.

 

[M.O.Ther]

As I understand it, and I've studied it for some time, matching numbers started mid '66, like Beaverbikes sez. The '67 -Y (dash Y) indicated a mid year wiring change, where the zener diode was moved from under the seat on a plate heat sink to a finned heat sink under the lower triple tree, requiring a different wiring harness. This -Y appears only on the motor.

The bikes with the Y and no dash are 1970 bikes with what appears to be '67 numbers (but all the later model's features, like unc threads and fairing lugs on the steering tube.) The Y appears on both the engine and frame on these bikes. There are stories about leftover bikes and dock strikes most of which have been debunked. My personal theory is that it was a scheme by then financially strapped BSA to convince the British government that these bikes had already been taxed. (British taxes were high enough in the late '60's that most of the Beatles and the Rolling Stones moved to the United States.)

The way the bikes were numbered changed again in mid '69. An early '69 Lightning, for instance will start with A65LC (the C being for the '69 model year.) Mid year the numbers started with two alpha characters for example DCxxxxxA65L, the D being for March and the C still being the '69 model year. I have a '69 Lightning (CCxxxxxA65L) and a '70 Lightning (A65LAxxxxY) one of the Y bikes.

And Tony, you're right about the '65 and earlier twins all having A50 frame designations, and the 650's having A65 engine designations, but according to Bacon and the 30 or so threads on the subject at Britbike.com, the numerical characters themselves did not match either. In fact I'd be pretty suspicious of a bike that did.

 

[beaverbikes]

Yeah, the A50 frame bikes, frame # wasn't anything like the engine # for either A65s or A50s. M.O. I like that theory about the dash Y, but what about the Hornets and their ET ignition? I don't think they got any wiring changes. Lots of 67 Hornets have the dash Y.

To answer KillSwitch, we don't know why the dash Y is on his title......I guess somebody somewhere just assumed frame and motor numbers were identical and the engine number was easier to read. I just checked the paperwork on my 67 which came to me with a Kansas title- it does have the Y in the VIN. But it isn't on the frame. Tell the inspection cats it is very common, and tell em what M.O. said.

 

[M.O.Ther]

I don't think there are any absolutes when it comes to BSA numbering. On the '67 -Y bikes I suspect that since the wiring change was "starting with #xxxxx" that all the engines got stamped with the -Y after that number. Seems like something a factory would do.

It doesn't surprise me that after years of transferring titles, and obtaining lost titles, especially in motorcycles where some brands have the VIN on the frame and others on the motor, that things get a little fuzzy. I'm in the process of contributing to the fuzziness. Since my '70 Y bike came to me without a title, I'm trying to get it titled as a '67, which is what the numbers look like. In Ohio, motorcycles manufactured after 1/1/68 are required to have turn indicators.

Here's a copy of a 1970 BSA service bulletin where BSA acknowledges the Y bikes:

 

[KillSwitch]

Thanks guys , I'll print this out to show him.

 

[beaverbikes]

Thats the one thing I haven't known, whether the dash Y started at a certain number and all engines built after that number were dash Y.

 

[beaverbikes]

I rolled out my 67 Hornet today, and its easy to see why the engine number is the one which made it onto the title. West coast model Hornet, and the original factory TT pipes are mounted hard to the frame right there where the flat spot for frame number is. You have to pull the pipe to check frame #.

 

[beaverbikes]

Just to stir up a little more Y and dash Y stuff, I just noticed one of the posters on this site has a nice looking 70 A65 engine on ebay. Because of the Y deal, he has it misidentified as a 67 engine.

 

[M.O.Ther]

My '70 Lightning Y bike is actually a bitsa. It has a '70 Y Lightning number on the frame, but it has a '67 -Y Spitfire engine in it.

 

[baron_beeza]

The Dash Y engines are common and started appearing early in the 1967 model production.

The Ebay engine is a 1970 model. similar but completely different.

It is easy to distinguish between them as the models are just physically so different.
A little like Kim and Kim. Same names but different genders. Most guys would be able to tell the difference there.

The stories about dock strikes, exchange rates, stored bikes, increased warranty etc are just rumours. None have any foundation. 1967 was one of the biggest production run seasons for BSA twins. A very profitable year for the factory and the Dash Y bikes were being exported even before the Xmas of 1966.

The Y bikes of 1970 are completely different, and have the suffix stamped on the frame also. As can be seen from the Service Bulletin shown above the bikes were 1970 models. Furthermore the American market offered a 180 day warranty on all 1970 model bikes... sold after March 1st...not just the twins.

I think the Y bikes of 1970 were part of an export incentive or tax avoidance scheme. The factory certainly did not advertise their existence.
Then again it is just as difficult to find anything published or in writing about the 1967 Dash Y bikes as well.

The BSAOC UK website is being updated. Once the corrected dating lists appear there then the others will be amended in due course.

 

[Gary E]

I'll be posting some info on the Britbike Forum, within the BSA board, in the "EBay A65 Dating Question" thread this weekend with information that will help explain the "-Y" stamping on the Hornet engines. It has nothing to with electrics. The source of the information is a factory document.

I have 2 Hornets. I have studied the actual original factory production records while in the UK in 2010.

 

[beaverbikes]

Thanks Gary. I checked it out, good info.

 

[baron_beeza]

http://www.britbike.com/forums/ubbthreads.php?ubb=showflat&Number=403787&page=1

http://www.britbike.com/forums/ubbthreads.php?ubb=showflat&Number=404653&page=1

http://www.britbike.com/forums/ubbthreads.php?ubb=showflat&Number=404037&page=1

 

[KillSwitch]

Well the inspector checked the numbers and noticed the lack of a Y on the frame. I showed him this thread that I had printed out and he found it very interesting, OK'd the paper work and I now have a title and tag. Now to assemble all the parts and pieces in to a street legal { kinda } drag bike

 

[beaverbikes]

Soon be another Beezer back on the road!

 

[baron_beeza]

....

A Series Unit twins.

This range extended from 1962 until 1972.

Prior to 1966 the frames were designated A50, A50B and A50C. The engine numbers would have indicated the model along with a non matching number.
Early in the 1966 model year (from Eng 3200 approx) the engine and frame numbers were matching numbers and with the relevant model code. For example A65L 12345.

The 1967 to 1969 models were similar (still matching numbers) but with the addition of a letter indicating the model year.
A for 1967, B for 1968 and C for 1969.
For example A65TB12345 is a 1968 Thunderbolt.

From early 1969 season onwards the later style numbering sequence was utilised.
This code was the same as Triumph also adopted with the season Month and Year designator added.
A50R XD012345 for a 1970 model Royal Star. XD indicating December 1970 model season.

Notes;

Many 1967 model bikes had a Dash Y suffix stamped on the engine number. This was done at the factory to advise the later 3 pipe oil manifold had been fitted. A65HA7731-Y.

To add to the confusion the Y suffix was added to other models and seasons also.

A large batch of A65SA numbered Spitfires have MkIV physical and styling features. That range is generally of the style A65SA1*****Y. These bikes are 1968 models identical to the A65SB machines.

A percentage of 1969 and 1970 manufactured bikes also have the Y suffix. Indeed the numbering sequence is similar to that of 1967 range machines. A65LA12345Y for example.
The differences, apart from the obvious styling, are that the frame number also has the suffix and all the engines are stamped on the raised and embossed engine pad.
These machines are 1969 or 1970 models.