Stella - 1977D survivor, back on the road.

I'm surprised by the low output from the original. Did you test it and does it have a bad diode? When I changed mine to a modern one, I saw no change in output. I was hoping for a little. I had read that a modern rectifier worked more efficiently and could give a small increase.

I must say, all this electrical problem posting will have me checking my system more often, lol. It seems good but obviously that can change quickly. I too need to install and actual volt meter. I have a color changing L.E.D. that indicates I'm charging, but it doesn't give me numbers.
 
Wish I were there, with my variable power supply. I'd put your battery on the bench, and hook-up with 14.2 charging volts, make note of the charging current.

Then I'd jostle/rattle/rock the battery, simulating bike vibrations, and note any changes to charging voltage and current.

Not sure about AGMs, but you oughta see some of the results I've gotten with certain old, seemingly good, lead/acid batteries. Almost like dead shorts, from cracked/cracking plates and lead sulphate deposits...
 
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I'm with 5Twins, it's got me checking my charging system all the time too. Every time I return from a ride , I flip my seat up and check the charge rate with my multi meter. I leave the meter on the bench all the time now just so I can quickly access it, and I have a couple more eBay rectifiers in my shopping cart just waiting for me to pay for them.
Also. If anyone finds a good little handlebar mount voltmeter let me know. I want one.
Keep swinging there Daniel, my money's on you to figure this thing out.
 
Mailman said:
I'm with 5Twins, it's got me checking my charging system all the time too. Every time I return from a ride , I flip my seat up and check the charge rate with my multi meter. I leave the meter on the bench all the time now just so I can quickly access it, and I have a couple more eBay rectifiers in my shopping cart just waiting for me to pay for them.
Also. If anyone finds a good little handlebar mount voltmeter let me know. I want one.
Keep swinging there Daniel, my money's on you to figure this thing out.
Click to expand...

Mine too - Stella is waaaaayyyy to cool to loose on this one. Daniel will nail this down like a wall-to-wall carpet and we will all benefit from the learning along the way.

As for DVMs - check out my post in "What have done with your XS today" - from yesterday. I found this cool little handlebar mounted digital voltmeter on-line from China for about $4.30. Just search on "motorcycle voltmeters". It was so cheap, I bought one for each bike plus a spare (just in case another bike follows me home....).;) Delivery was within a week or two I think and it even came directly to me in Canada without duty (got one by those greedy Ottawa b@stards..).

It even has two USB charge ports so Lucille has actually joined the 21st Century!

Cheers,

Pete

PS - hey! I just noticed that in my excitement to get Lucille going, I forgot the rubber bootie that goes over the banjo bolt on the master cylinder. I have it - I just haven't put it on yet. Oh well, lots more to do on my riding friend.

Cheapo-Chinoise-Voltmeter_Lucille.JPG
 
I hear some are concerned I may have gotten discouraged with this little project and given up. Have no fear, I ain't letting this ol' girl down.

Recent tracking shows my new rectifiers as out for delivery, two days early!
 
The Windy Nation rectifiers give me great hope. They're about half the size of the Chinese variety, but much the same weight. You can feel the difference in build quality in your hand.
IMG_20170407_110609715.jpg


I've also installed a small digital voltmeter in the old brake lamp spot. It's taking its reading off the brown supply wire in the head lamp bucket. That's a 16g wire running directly from the 'main switched power' relay under the seat. Measured against the battery, it's seeing a .03v drop.
IMG_20170407_112255437.jpg
IMG_20170407_112304336.jpg


At first startup with the new rectifier, max charge of 14.15v at the battery. My dash voltmeter reads 14.1v @ 2000+rpm.
IMG_20170407_124951481.jpg
IMG_20170407_125059246.jpg
IMG_20170407_125125815.jpg


Time to ride.
 
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That cool Daniel - really like the DVM installation (waaaayyyy better than the clunky set up on Lucille).

Anyhow - go ride - and stick at it!
Pete
 
15 miles over about 30 minutes, lighting circuit removed from the equation by pulling its fuse. Nothing conclusive, yet.

Upon taking off, my charge dropped to 14.0v, soon straddling 13.9/14.0v. I stopped and measured the rectifier diodes. By eight miles in, the charge fell to 13.8v and stayed there until the very end of this test ride. In the last 1/4m there's a long light I sat at. Immediately off that light the max charge was 13.7v, but in the last 1/4m stretch to home it raised to 13.8v.

At start, 14.1v
Blk lead on + 407 406 396
Red lead on - 394 396 409

A short way down the road, 13.9/14.0v
367 367 358
360 362 377

~8 miles in, 13.8v
364 364 355
352 354 371
+ to - 626

Very end of 15miles, 30m, 13.7/13.8v
355 355 346
343 346 362
609

I'm now letting things cool to see if the readings raise back up.

With the Chinese rectifier, I noticed one neg diode increase its voltage drop much more than the others before failing. These seem to be dropping, less drastically, and evenly.
 

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