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Well, the front wheel trued up well. All the spokes were removed and oiled up, and the wheel set up with a dial indicator on a truing stand, and I worked it to .040" axial runout and .050" radial runout, which is as good as it's going to get due to 60 years worth of dents, and the spot where the rim was welded when it was made, so I'm calling that good. (Might not be 60 years worth, since the rim is a 19" and the bike came with a 20" in 1962, but a long time, anyway).

Got the forks installed back into the clamps. Took an extra half hour because somewhere I dropped the forking pulling tool, and it dinged up some of the threads and I couldn't turn the nut by hand at a few spots, so had to take a riffle file and work down the flat places, but then the forks went back in like they're supposed to, including my NOS fork ears which look too nice for the rest of the bike. That's a dangerous slippery slope though, and I'm not taking the bait!

It looks to me, based on the coil, that the bike has a distributor AND Energy Transfer ignition, which should be fun .... I got a few things to learn, I can see.

Lannis

Lannis, I don't know if anyone has said but the C15T/S were Energy Transfer Ign so wouldn't have a battery or tray.

Hmm, I better have a closer look at the parts book.

The PO had cobbled a battery holder onto it with plumbers strapping, certainly not how it came....

Lannis

Well I've finished up the C15S front end .... New headstock and wheel bearings, fork headlight ears, fork seals, gaiters, wheels trued up, new tire and tube. Cleaned, wire-brushed, and painted everything I didn't replace, and it suits me ok.

Now onto some wiring, take the rear wheel and swingarm out, new bearings, bushings, Shocks, tire, tube, true up the wheel, and get closer to dealing with the motor and transmission.....

Lannis

Gonna need a shower tonight for sure.

Took the rear wheel out of the C15. Brake adjuster was seized on the rod, so that will need a die to fix the threads. The speedometer drive was "jammed" onto the axle .... had to "thread" it off as if the internal diameter of the casing was tapped. Hope I didn't damage it, but it hasn't been used for a long time - cable opening and rear cap were gone and it's been open to mud and water for who-knows-how-many years. I'll put it aside to work on later.

Wheel was massively rusty. The tire was bonded to the rim by rust, and would not move enough to lever it off, so had to use a Sawzall. A "Gum-Dipped" Firestone 4.00 x 18; haven't seen one of those for 30 years. I've wire-brushed the wheel as well as I can, but I'll have to put a strain on my conscience to use this wheel. I think it's still structurally sound - the bead-mounting area is fairly smooth, and I'll clean up the spokes, nipples, and threads tomorrow. Ugly, though. If I like this bike once I get it done, I'll build a new pair of wheels. The rear wheel/hub assembly with the brake must weigh 50 pounds.

The worn and hooked 68-tooth sprocket came off fairly easily, and the brakes are in good shape. I'll have to pick a ratio that will work for what I want ot use it for; ride it on the road to the trail.

I've gotten one shock off; the other one is seized up pretty good, but since I'm not going to save it (it's rusty and bent), I can take it off with a big hammer. Hoping that the swingarm is usable, looks pretty straight on the bike.

Onward and upward. February was the front end, March the rear end, April the electrics and tinware, and May-July the motor/trans (I HOPE!)

Lannis

Taking apart the rear suspension on the C15S. Down to the swinging arm. It has a small amount of side-to-side play, maybe 1/8" at the rear of the axle slot, doesn't appear to have any looseness at the actual pivot.

The manual says to take the swingarm bolt loose, tap it out of the swingarm, lift out the swingarm, and remove the bushings with a suitable drift?

Are these "silentbloc" bushings, and this stuff of "tapping with a suitable drift" just a pipe dream that actually turns into using flamethrowers, jackhammers, and Sawzalls to get them out, or do they actually go in and out like the manual says? And if I were to replace them, how much side-to-side play would I expect from a new set at the end of the swingarm? Zero? or is a little play to be expected, in which case I'll just leave them.

Lannis

It's supposed to be Iron Rule #1 of working on old Britbikes - "NEVER ADD UP THE BILLS", but I can't resist.

So far on the C15S - new tires, new wheel and suspension bearings, fork seals, gaiters and gaiter clamps, NOS fork ears, steering head bearings, cap nuts, new sprockets, headlight and dimmer switches, circlips, cables, gas tank rubbers and mounts, and some bolts and dust covers, I'm up to about $600.

Primary is off now, clutch looks to be in good shape, chainwheel and engine sprocket good, and no notched spots on the chainwheel, although I haven't had the clutch off yet to see what kind of shape the friction material is in....

Lannis

Better avoid any more "adding up".
I think you need to know about the rod bearing. Time to pull the top end off.

You can pretty much count on replacing the cables, fork seals, tyres and wheel bearings on any old machine which hasn't been worked on in 20 years, and far too many that have been as well.

Steering head bearings are a bit of a lottery. So are fork stanchions and bushes, so you got lucky there. Doubly so, since you're in a wet area.

I'd have replaced the brake shoes as well. The linings are usually impregnated with oil and grease, worn, and just for luck, used asbestos.

Once you get into the engine, new valve springs are cheap insurance as well.

The pre competition frame used a hollow pin with 2 large threaded bolts on each end with greasing nipples, the bushes were bronze steel backed bushes in the two swingarm ends and end float was adjusted with shims. The pin should be fixed in its frame housing and the swingarm moves relative to the fixed pin. Based on no up and down play and 1/8 sideways play then leave as is and just make sure the route for the grease is clear and the pin is fixed in the frame housing.

See page 38 & 42

https://www.bsaunitsingles.com/Arch...1961-1964%20C15%20most%20models%20x.pdf.

The Silentloc bushes came in with the Comp frame

Thanks! Yes, I pretty much planned to replace every rubber bit, suspension bushings, wheel bearings, seals, Shocks, etc. I replaced the balls in the steering head, but the bearing races cleaned up smooth and nice, no "brinelling" or rust, and it's very smooth now that it's back together, right number of balls, and preloaded properly. The fork bushings felt like new - no water incursion, no corrosion, clean oil (although it might have been 40 years old or more), so they stayed.

The brake shoes, I won't know until get cables back on and try them. They sanded up nice and clean, still some meat on them over the rivets, and no scoring in the drum, so they MIGHT be OK - if not, it's an easy job to get to them and replace them after the bike's on the road. Good reminder about the valve springs - since I knew that I would at least take off the top end, I didn't compression check it (too late now), although I could still do a leak-down test if I wanted to. I will very likely at least lap in the valves, replace the springs, and hope the cylinder just cleans up at its current bore for new rings, although who knows why the PO quit riding it; there could be a disaster lurking in there. Overall, it looks like a bike that hasn't been ridden in 30 - 40 years (the tires, battery and patina indicate that), but is not worn out or wrecked hard .... an easy project so far. Everything is coming apart with normal wrenches, no cutting torches or impact tools required (although I did have to cut the tires off the wheels), fork tubes pass the roll test, wheels about 3/16" out in axial runout to start truing up, etc.

Waiting on a few bits now (cables, shock bushings, switches) to finish up the frame and suspension jobs and get the lighting wiring done, then the engine and ignition are next.

Lannis

kommando -

Mine is the frame listed under the "C15 Competition" diagram .... the "2 large threaded bolts on each end with greasing nipples".

I notice that the parts diagrams use "C15 Standard" for the road model, "C15 Competition" for the C15S Scrambler and C15T Trials in places where they are the same, and a "C15 Trials Pastoral" for the parts specific to the Trials models.

I measured again, and it's not even quite 1/8" side-to-side movement at the axle slot, so as you say I'm going to grease it and leave it.

Thanks!!

Working on the C15 a bit at a time. All the parts I've ordered so far are in except for the lower bushes for the Girling Shocks ... the Competition model has a 1/2" shock lower bolt bushing, where most small BSAs are 3/8". I tried drilling out the 3/8" to 1/2", but the rubber heated and flexed too much and even on a drill press, I couldn't drill straight. So a new pair ordered from England, apparently it's on a very slow boat.

Starting on the wiring .... I'm studying Rupert Ratio but don't quite understand exactly which bikes came with batteries and which didn't. I suspect that this '62 C15S with Energy Transfer ignition did NOT come with a battery, as there is no battery box, although one has been cobbled on with plumber's strapping. It has a non-Brit taillight, and had a standard C15S headlamp shell bolted to the forks with homemade mounts.

Couple of questions - How did these bikes do with lights and no battery? I don't intend to ride it at night for any reason; if it has a good alternator, good rectifier, and new wiring, shouldn't the 6V lights work OK, even though they cut off when the engine quits? I'm sure I'll replace the 60-year-old rectifier with a modern electronic replacement - no need in asking TOO much out of these old components.

And if I do decide to wire a battery in, how would it be wired up to a formerly batteryless system? I'm just going to have a simple two-position ignition switch, the light and high-beam switch in the headlight, horn on the handlebar, and kill switch on the handlebar center like original.....

Lannis

How many stator wires are there? 2 or 3 will be a battery system stator, 4 or 5 will be an ET stator.

A 1962 C15S should be ET.

If it was originally an ET ignition , it used a 4 wire stator ( or a 5 wire stator with one ignition wire added to ground , making it functionally a four wire )
wired like this , all AC , no rectifier ( a light bulb must be load matched , 24/24 watts i think )

there is no requirement that you stick with this system ... and / or it may have already been modified .

the ET points cam is a very different than a DC points cam .
the dc cam won't work on ET
and the ET cam will work on dc ... but only by extremely over dwelling the coil . ( sometime racers did this )

if the ET side works , you could keep the ignition and rectify
just the lighting side , to charge a small battery ... and run led lighting ( there's plenty of power to run LEDs )

or run the smaller 10.5 amp , three phase stator , to rectifier / regulator >>to external capacitor >> to points ignition and normal lighing
( the rectified output from three phase stator (with external capacitor ) is smooth enough to run points ( or a Boyer ) without a battery

All right. Got all the tinware off, exposed all the wiring.

1) The existing wiring is a bodge job. All the wires are coming out except the 4 wires coming from the stator.

2) The PO had wired in a plate rectifier using 3 of the 4 stator wires and the other one hanging in the breeze, with a 6v battery "hot" (Neg) running to the ET coil, and battery POS running to the rectifier ground. I have no idea if the bike ever functioned, ran, charged the battery, or anything wired up like this, so I'm pulling it all out and not trying to guess how it worked or was supposed to work.

3) I want to wire it up stock, AC-only, ET batteryless. I need to check the points cam to make sure it has the "ET Dwell" profile, and check the position of the rotor to make sure it's in the right orientation so that max output comes at points-breaking time. I'll use the light bulbs as voltage regulators as original , and I've bought the proper "rolling dice" hi/lo beam switch to make sure a bulb is always in circuit as the switch operates. I don't know the magnetism of the rotor - I assume that the old rule applies "if you can pick it up with a hammerhead and it supports its own weight" then the magnetism is OK. I won't really know if the stator is putting out anything until I can kick it over and catch the momentary output on a meter; meanwhile, I can do the continuity tests to make sure stator internal wires aren't broken.

An original NOS Luca ET coil is $500; the reproduction EMGO coils (like every lawnmower and chainsaw on earth uses) are $18, so that's a no -brainer.

Does this sound like a plan or is there a monstrous problem in there somewhere?

Lannis

Unlike the twins the unit singles do not seem to have bothered with a rotor you can adjust position relative to the crank to get best spark but you may be lucky. So only 1 position for the rotor, it will work or it won't. Same test, rotor either hangs off a large screwdriver to show its good, or cannot in which case its consider going capacitor plus 12V and normal points.