New Member - Bristol, CT

[Hartj.ct]

Wanted to introduce myself as a new member.  My name is Jim and have been on two wheeled motor bikes since 5 yr old.  Now 50, I’m interested in a unique classic, and I’m close to acquiring a BSA in rough condition. I think it’s an A10 ridgid early 50’s.  A selling price hasn’t been determined, but feel that will be worked out.  I’ll post a photo and would look forward to your feedback on the condition, value, build suggestions…etc. Also looking forward to hear and see more about your restorations and projects.

Hope all is well, and thank you in advance for any helpful feedback.

[BagONails]

Hi Jim, welcome to the forum.

That looks interesting, seems reasonably complete, might be a 'Longstroke' A7 500cc actually but you need to check the numbers stamped on the crankcase neck just below the barrel joint on the left side.

I've been looking at a similar machine here, a 49 plunger A7 also an LS.

They are a bit special and quite rare as they were not made for as long as the later models but they have a unique charm all their own I think.

We even have a whole section here devoted to the dear old chooks :
https://www.a7a10.net/forum/index.php?board=38.0

Good luck with your negotiations and you've found an absolute goldmine of information and help on here.
Cheers
Ian

[Hartj.ct]

Thanks Ian!!  I’ll check then crank case.  I was looking on the frame behind the headlamp, I guess that’s why I couldn’t find it…. I’ll be back tomorrow and see what I can find.  The owner has 5 other various BSA’s completely restored, I think all for sale.  This is the only one in my budget. I could inquire and post photos of the other bikes if any one is interested.  All Vintage BSA’s…

[Brian]

Thats a 500cc A7 "longstroke". And if my eyes are not playing tricks on me its very early one, it appears to have the drop down centre stand. I would expect the engine and frame to begin with the letter X.

[Hartj.ct]

Yes! It does have the drop down center stand, I noticed that in person.  Also I think it has some kind of “split shift” lever on the right side.  Maybe like a high and low gear?

[Brian]

No just the standard four speed box. Can you put a pic with an arrow pointing to the "split shift" lever you mention, we will be able to let you know what it is then.

[Hartj.ct]

There is a good chance it’s a ‘47 based something owner stated. See photo of lever.  Look to be above kick start shaft. Or maybe clutch lever?

[Brian]

Thats the clutch lever.

[CheeserBeezer]

That is a very interesting and rare bike. The following is my opinion and may be a bit contentious! I was in the process of restoring one of these about ten years ago and gave up with it and sold it on. When I was rebuilding the engine I came to the view that the original design and construction was very poor. The lubrication system seemed inadequate and certain aspects of design and construction seemed very weak. Generally, the crankshaft, conrods, cam and followers all seemed to be flawed for various reasons. The lubrication of the cam and followers was particularly poor and, in the very early models the valve gear relied on mist, but this can be upgraded. The reasons BSA discontinued the bike after only four years of production would, I guess, be largely due to the mechanical and design issues I've mentioned. The engine introduced in 1950, i.e. the 'shortstroke' A7 and A10 is far superior and will give many miles of trouble-free pleasure if built properly. However, the bike you have identified is rare and deserves to be given a chance. If you buy it and restore it, you will have a rare bike that gets a lot of attention. If you intend to do some longish runs and use the bike regularly you may look elsewhere or buy something in addition. There are a number of people on this forum who own 'longstrokes' and I dare say I've already offended them so I apologise. BSA, who had a policy of producing the same model in various forms for extended periods of time, dropped the 'longstroke' after only four years of production, probably for good reason. Sorry!

[Swarfcut]

 Jim....    I'd go along entirely with CB's thoughts. It is indeed a Longstroke A7. A later version engine by the look of the outer timing cover with it's three lower bolts (only two on the first models). This is a further conundrum, the drop down stand only featured on the first bikes in production. If I'm wrong, and it is a contemporary motor with the very early engine design, this has its own unique crankshaft as well, so presents further problems if a replacement is necessary.

 The rest of the bike has the major unique parts in situ...the bits missing are parts that fit the later models of Rigid and Plunger framed bikes, that's why they have been parted out, but are more or less readily available. If the front left side engine mounting has a dome, (to take a short dynamo) its likely to be an early engine. Hole in the mount for a long dynamo? It's later. Frame number is on left side of Steering Head Frame Lug. Engine number...left side of crankcase, just below barrel. These will confirm what's what.

 The good news is that if necessary a better design later shortstroke engine will fit straight into the rigid frame.

 It is a very rare find, well worth preserving, and despite its shortcomings, well worth a punt. Value needs to be a sensible one, rarity does not mean it's highly desirable.

 Swarfy.

[muskrat]

G'day Harty. 
Wow, what a find! I'd say 1947/8
But in saying that I agree with CheeserBeezer. Not only the longevity of the design but also the difficulty of bring back to concourse.
I've never had a long stroke and luv my 51 A7 for over 40 years. I have a friend who has a 49 L/S and luvs it just as much.
Check out the L/S section. https://www.a7a10.net/forum/index.php?board=38.0
Cheers
Swarfy got in first.
 

[Greybeard]

 

[KiwiGF]

Along the lines of wot cheesabeeza said, not all of the bikes produced by BSA were “winners”, I had a 30’s pre war single cyl basket case with girder fork case for a while and sold it on when I came to my senses and realised there was a reason the crankcases were cracked, and gears in the gearbox had missing teeth. They were just not built as solidly or as well designed as the post war pre units singles (B31/33).

Having said that, I Knew a guy with an early rigid a7 longstroke, and he rode it in a spirited fashion to quite a few rallies and it kept up easily with the other post war pre unit twins, but it attracted far more attention (and trophies) for it’s rarity. They are a very good looking bike  and light too.

[Hartj.ct]

Wow, I am amazed at the great feedback and I very much appreciate it.  Despite the less than perfect design, I would like restore to its original design.  I’ve got another bike and an old convertible so the BSA would be a special occasion bike. I’m going to get a better look today and get a number off the motor.  I think I have a good resource for parts and hope that will make the rebuild a little easier.  Can’t thank you all enough for the great information!!

[Hartj.ct]

I also wanted to mention…for me, this isn’t about getting a bike to restore because it would be worth a lot of money.  I can careless to be honest and no disrespect for anyone who does.  The value for me comes from the experience of bringing back a unique piece of history with my own two hands…it’s likely not going to be a show piece and I hope I can keep the original “patina” so to speak.  Look to make it something that is clean and mechanically sound….if something needs paint then I paint it right…if something needs to be repaired I learn how… If something was supposed to be shiny, I’ll polish it. If it’s dirty, I’ll clean it.   

Unfortunately I can’t afford to chrome dip and candy coat everything.