JFerg
Just got it firing!
I've just read through Levoz' thread below, but I have a different issue.
I've just put my Le Mans II back on the road after a major (200,000km) maintenance spree. This included new alternator brushes. Despite the bike only being apart about 3 weeks, I had to flash the alternator to get it to start charging. Then all was good until this week.
2,000km since the rebuild completed, all is fine with the slight qualification that I need to hit 4 grand after a start for the charge light to extinguish. No biggie, and not a problem. This week I was out for a ride with some mates. We stopped at the pub for lunch. After lunch I led out, then waited a few hundred yards away for everyone to get organised. When I re-started the engine from there, the charge light did not extinguish. I was a bit peeved and started calculating how far I'd get, given I was 100 miles from home; but twenty minutes later, during normal riding, the light went out and the voltage came back up. At the coffee stop and at four further starts after that, it would not extinguish.
So I put it up on the bench. Everything is fine. Brushes are bedding in nicely, not snagged, connections are all good, a substitute new (out of the box) regulator made no change. In frustration I flashed the bastard again and guess what? Problem is gone again. Still on the bench and in disbelief, I reckon that I've made a further ten starts at least, over 5 days, and each time the light goes out and the charging kicks in at 4 grand the first time, under 1500 rpm thereafter.
The theory of flashing the alternator is that you restore the residual magnetism that ebbs away when the magnetic circuits are broken, which is what happens when you take the alternator apart and put the bits in a box. It's this residual magnetism that allows the alternator to start charging. The residual shouldn't be lost in an assembled unit (except maybe over a very, very long time unused) and certainly can't be lost in minute, yet that's what seems to be happening.
Any and all wisdom greatly appreciated,
JFerg
I've just put my Le Mans II back on the road after a major (200,000km) maintenance spree. This included new alternator brushes. Despite the bike only being apart about 3 weeks, I had to flash the alternator to get it to start charging. Then all was good until this week.
2,000km since the rebuild completed, all is fine with the slight qualification that I need to hit 4 grand after a start for the charge light to extinguish. No biggie, and not a problem. This week I was out for a ride with some mates. We stopped at the pub for lunch. After lunch I led out, then waited a few hundred yards away for everyone to get organised. When I re-started the engine from there, the charge light did not extinguish. I was a bit peeved and started calculating how far I'd get, given I was 100 miles from home; but twenty minutes later, during normal riding, the light went out and the voltage came back up. At the coffee stop and at four further starts after that, it would not extinguish.
So I put it up on the bench. Everything is fine. Brushes are bedding in nicely, not snagged, connections are all good, a substitute new (out of the box) regulator made no change. In frustration I flashed the bastard again and guess what? Problem is gone again. Still on the bench and in disbelief, I reckon that I've made a further ten starts at least, over 5 days, and each time the light goes out and the charging kicks in at 4 grand the first time, under 1500 rpm thereafter.
The theory of flashing the alternator is that you restore the residual magnetism that ebbs away when the magnetic circuits are broken, which is what happens when you take the alternator apart and put the bits in a box. It's this residual magnetism that allows the alternator to start charging. The residual shouldn't be lost in an assembled unit (except maybe over a very, very long time unused) and certainly can't be lost in minute, yet that's what seems to be happening.
Any and all wisdom greatly appreciated,
JFerg