As I stated in my Humble Beginnings thread. I am reviving a '68 BSA Lightening for a neighbor. The bike hasn't run in 3 years or so. I cleaned the carburetors and adjusted the valves, oiled the top end, put 3 quarts of oil in it, kicked and kicked 'til I got oil to the top end, screwed in some new plugs and was ready to see if it would light off and then, believe it or not, I ran into some electrical issues. Who would'a thunk it?
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BSA stuff. Not the new one.
- Thread starter drgonzo
- Start date
That rocks Jim!
I am reminded of an episode of Madmen when Layne was going to kill himself with the exhaust from his brand new Jaguar XKE but alas it would not start.
In fairness to the queen this example has a somewhat butchered wiring harness.
I am reminded of an episode of Madmen when Layne was going to kill himself with the exhaust from his brand new Jaguar XKE but alas it would not start.
In fairness to the queen this example has a somewhat butchered wiring harness.
Since you brought up Lucas…. Is there a reason two legs would be tied together off the stator? I just ran into this on a 1972 Triumph. It’s a mutt mix match of parts. Took a phase out. I put it back to three phase and I’m using a solid state reg/rec. Still positive to ground tho.
Are you.... positive?
Same here... nothing major anyway.... justa' bunch of little niggles. Also had a '69 MGB that never gave me any electrical grief. Well... other than the fuel gauge never worked.
I jus' like makin' fun of 'em anyway.
They did tend to over complicate things though...
I like that wiring diagram!
The charging system, alternator, rectifier and zener I always found to be top notch. The only thing that ever failed was ignition coils on my 63 A65 Thunderbolt, curiously, both went at the same time.
Amal carbs were a different matter though, monoblock and MK1 concentrics were great, if a little messy with the tickler, but the Mk2 wasn't anywhere near as good, mostly just build quality.
Question, did any one ever manage to start a BSA twin on the emergency start position? I kicked and kicked and kicked until the kickstarter bent - nothing!
The charging system, alternator, rectifier and zener I always found to be top notch. The only thing that ever failed was ignition coils on my 63 A65 Thunderbolt, curiously, both went at the same time.
Amal carbs were a different matter though, monoblock and MK1 concentrics were great, if a little messy with the tickler, but the Mk2 wasn't anywhere near as good, mostly just build quality.
Question, did any one ever manage to start a BSA twin on the emergency start position? I kicked and kicked and kicked until the kickstarter bent - nothing!
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The two old Trumpets I've owned had easily the worst electrics of any bikes I've ever seen. But that was mostly down to age, neglect and bodging by generations of POs. If North Americans are not familiar with bodging, it's a technical term widely used in Britain for taking something that doesn't work - or even in some cases does work - and making it much worse by fixing it or 'improving' it with complete lack of understanding, technical skill or correct parts.
The horror of those messed-with electrical systems was so bad you spent less time blaming Joe Lucas, the Prince of Darkness, and more time blaming yourself for being stupid enough to buy the flaming thing.
The horror of those messed-with electrical systems was so bad you spent less time blaming Joe Lucas, the Prince of Darkness, and more time blaming yourself for being stupid enough to buy the flaming thing.
These old machines can be money pits for sure. Nothing last forever. Even charging systems are consumables. I try to be forgiving with 50 plus year old technology and engineering. It’s what they had. Then factor in cost. Get whet you pay for. Triumphs were affordable machines for the time. Yamahas definitely. Why I’m not the biggest fan of Harley. For the price, quality should be second to none. It’s not. Anyway, in the last 5 yrs I’ve worked in equipment service. I’ve learned so far: look at things from different angles. Ask questions. Don’t assume. Research. Not everything wears out the same. Currently, This p.o. Told me the bike had been rebuild when he bought it. Didn’t ride it much. It sat for eight years. Bullshit. Whole top end was shot. Pulling numbers off castings, it’s a Johnny Cash machine. Lol
Some folks might remember the story about the certified Norton mechanic, the graduate University of Illinois electrical engineer, and the Norton Electra that still refused to charge after around 40 hours of attention from those highly credentialed and capable individuals. Every component checked out on professional grade meters and oscilloscope, but in combination--no charge. And that's what the customer was told: "We can't find it. Your bike is cursed. No charge." The year was 1967 and the Norton was unmolested and fairly new, not something chewed on by mice and idiots and found hidden in a disused 2-holer.
Only thing known for sure is you have one SMART neighbor.
either that or you are exceedingly gullible. ;^)
Points wires as removed from a RUNNING commando.
mike in idaho
XS650 Addict
I doubt that's a three phase stator, just an earlier single phase one. Three wire Lucas alternators are used in the earlier charging setups, where the light switch turned on a second set of a/c coils, to keep up with the extra load of the lights. That was the same method as used by the Japanese at that time, known as the "balanced load" setup. Later Lucas stators are two wires, they put out full output all the time, the excess voltage being bled off with a zener diode. The two wire and three wire stators are essentially the same electrically, and interchangeable, with those two wires paired-up.
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Zener diode, yeah, I remember that. Had to charge the battery on my new, daily ridden 68 Bonnie every 3 or 4 weeks because the zener diode did such a damn fine job of bleeding off current.
I remember that the parts manager at the shop I worked, who was a brit bike guy, kept a dozen Zenor Diodes in stock at all times...we did sell lots of them though as this was in 1975 or so.
Well, I also own a Aermacchi HD Sprint. Seems I'm just a glutton for punishment.Only thing known for sure is you have one SMART neighbor.
either that or you are exceedingly gullible. ;^)
View attachment 212137
Points wires as removed from a RUNNING commando.
hovel
ol' stupid
I'm getting a lot of mileage out of that wonderful wiring diagram. I sent it to an old friend who does better-than-amateur-grade nut and bolt British car restorations. My wife drove a whole succession of late 60's-early 70's MG Midgets and the electrics never gave me problems, just as Jim related.
I'm down to one Brit..... I completely wired it with a Boyer ignition.. 12v Positive ground. Use a dash mounted digital volt meter. One kick... starts.... with lights on and sitting at the light... the meter drops from green to yellow. light turns red and I pull away, meter goes back to green. I was headed home from Slimy Crud in a horizonal driving rain storm.... thinking I'm screwed because I know who wired the bike. Didn't skip a beat. 
