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Mark Z advice is good for pre 1970 bikes.
But
1970 A65 has solid bushed swing arm, not like the previous silentbloc bushes, take the swing arm and pivot bolt/ bearing tube assembly back to shop that pressed in the bushes . Ask them to ream the bushes to allow a slip fit of the pivot tube , IIRC you need a one inch reamer. DO NOT use a BFH.

Diagram of 1970 SA assembly. https://draganfly.co.uk/product-category/bsa/sparesparts-for-bsa-a50-a65/1970/swinging-arm-70/

Mark Z ..... "I like the socket idea, but it seems like it would have to be a pretty hefty drill to turn the motor over, unless it's done before the valve train is in place"

Surprisingly not I just have a bog standard Dewalt and my B44s swing over pretty darn quick with just the deco lever pulled, enough for me to ponder on electric starts!!?? but there again where is the fun in that?

Gavin thank you. I think I should be able to push the pin through and take it out again reasonably easily, but right now I get a mechanical clunk that I really don't like and think that hammering will make worse.

In an ideal world, BSA would have given the threaded part a smaller OD than the main pin, and even put a taper between the threads and the main pin. That way the pin could guide itself. I'll see if I can make something up with a socket or whatever that fits in the ID of the pin.

Agree with Allen, spinning the oil pump around via the tacho drive with a cordless drill and piece of rubber as a flexi drive is a really good way of priming the oil systems on A65 engines, there's a good description of how to do it on the E&V website Here

Not too sure about the swinging arm bushings, but it sounds like the bushings are misaligned so get the workshop to try pressing them in again paying more attention to having them aligned.

I may have got the wrong end of the stick, re reading your post, its the bolt not passing through the "dollies", bobbins, pucks whatever, this is not the bearing surface , the pucks should freely rotate in the outer bushes, when the bolt is tightened the whole bolt puck sandwich is locked together, there may be a missalignment or burr between the puck s, if its just a burr dress clean with a round file, if the centre spacer tube is out of place it can be recentred with a tapered podger.

Hey Gavin,

These are the bushings I use: https://www.classicbritishspares.co...ent-block-bushings?variant=8906140024876

There are two of them pressed into the swingarm, with the narrow ends meeting (with a small gap) in the middle. This is where I experience a sharp ding sound and get no more motion. I've tried tapping (but not thumping) to get the pin through and it just won't go.

I'm taking it back to the shop tomorrow to get it reamed. We'll see how that turns out

- Mark

Gavin it looks like Psychopasta frame is older than his engine. I believe he changed old silentblocks to new ones, so he has different / older swingarm with this frame. I don't think you could use older swingarm wth 70 frame either.

Ahh, 70 motor, older frame, that makes sense , ignore everything I said about the swing arm , do what Mark Z says.

I didn't really pay attention to the year, the description just depicted Silentbloc bushings. FWIW, I believe in some older thread it was established that some very early '70s had Silentblocs. Same old BSA story, leftover frames? Who knows?

Psychopasta, if you're getting a solid "tink" driving in the pivot pin, I guess it is time to take it back to the shop and see what's going on.

Indeed so. It’s back being reamed. I’ll post when it’s back

No news on the swingarm yet but I have been busy on the front end.

I got the fork yokes powder coated and reassembled the forks as described earlier:



I also painted the Betor handlebar mounts



and mounted the handlebars onto the top yoke like so:


There's not much room to access the first row on nuts when the yoke is on the bike, but it is possible, just awkward



I then assembled one of the forks. These parts:

Go into the forks leg itself and the circlip holds it all together:

Then drop the piston and spring down and finagle it until the rod comes through the hole:

put the fork leg back on and get the Allen screw up inside the leg until it secures the piston. Turn the whole thing upside down and add the seal and circlip:


Then put back on bike with gaiters:


and drop the spring in and tighten up the top bolt. Job's a good 'un

I haven't added oil yet, and I'll get the second one on soon.

Nice! Good move on the Betors - almost any other forks are more straightforward and easier to deal with (and perform better) than the OE BSA forks.

So I've heard, but the Betors are pretty primitive. There's no bottom bushing on the chrome leg so the chrome just rubs against bare ally. But I am pleased, I feel like I'm making real progress.

So do a lot of forks, both on japanese bikes and 71-on Triumph/BSA bikes. Think of it that you have full stanchion support whilst any given length is within the slider.

Got the other fork rebuilt using the same process. All was good, except the powder coater had put a screw of indeterminate thread into the drain hole to mask it. The screw wasn't the right size, so they used masking tape the thicken it up, and then during the heating stage it melted to a gooey mess that made it very hard to get the screw out. Nevertheless, I persisted. I had to use a tap to clean the thread out afterwards. But then the second fork was on!



Yahoo! I took the front axle:


and locked one fork down and let the other move so that the axle would go through it, and then locked that leg down too. I then offered up the front wheel, and with a little jiggery-pokery with the jack under the bike got the wheel on!




and got the pinch bolts on. Nothing is torqued down tightly yet of course. I still need to do the full wheel rebuild.

Speaking of which, this is the front wheel fully built:

Anyone recognize what it is, and if so what bearings it takes?

BTW, the wheel is very crusty:

Does any of that YouTube tinfoil-and-coke stuff work? I need to clean this up, does anything work as well as it does on the Tube?

I've tried the tinfoil and coke method on a wheel with similar corrosion, it didn't work too well. I think it works best where the rust holes are small and foil seems to fill the small hole. The coke is useful as it contains phosphoric acid which eats rust.

Another option is to simply polish the wheel using Solvol Autosol or similar chrome polish.

The real answer is to rebuild the wheel with new spokes and rim, its not too hard to diy, or take to a workshop and let them do it.

The front wheel is BSA single leading shoe , 8" , half width hub, these were fitted to many Beesas , they are quickly detachable (QD).

I just change rims and spokes to a new items if rims are heavily corroded, their look from outside is one problem but usually they are also corroded inside which could be a problem after you install new tubes. And I don't feel safe on corroded wheels.

So went out to the garage today and arse! the left-hand fork leg wet the bed overnight:

The right hand one was good and tight, no leaks. I'll get onto that soon. Today's job is sorting out he ignition coils and the trigger box for the electronic ignition:

The two-pin connector (hard to see against the bottle of isopropyl alcohol) goes to the 'contact breaker' magnetic switch, and the three pin connector has red and black serving the coils and white going to earth. The trigger box is held on with velcro and cable ties, as there's nothing to screw into or through. I plan on making the connections and fitting to the bike tomorrow.

White to earth? Did you convert to negative earth? (Sorry if you already said that; it's a long thread.)

+1 with Gavin.
They are a very good brake--- I had one on a 1954 A7 Shooting Star.
Back in the day the sidecar racers would take two of these brakes and make a single double sided brake for the front brake.
By the standards of the day it was a great stopper!

Yep, 12volts negative earth :-)

If you convert to negative earth I will not help anymore. guaranteed either you or some FDPO, will not realise the swap, look at a diagram and fit the batery backwards. dont do it.

I'm also not an advocate of converting to negative earth, but the confusion can be alleviated by:
1. Drawing and maintaining one's own schematic (with a bold header that says "Negative Earth"),
2. Changing all "earthing" wires from red to black,
3. Labeling battery leads with "POS" and "NEG" stickers.