Stella - 1977D survivor, back on the road.

I see. Well, for the guy whose last two rectifiers each crapped out within 30 minutes of riding, once requiring a tow home, a 30m driveway test seemed prudent on the third before heading out on the road.

That said, I've just came back from a 27 mile spin in increasingly greater radii from home. Max charge slowly dropped from 14.2v at the start down to 13.9v at about ten miles and held there. At the end of the ride the rectifier was evenly warm, but not hot.

Not perfect, but cautiously optimistic in Phoenix.

Hey, Pete? I enjoyed it.
 
Well done, now you're making real progress! These older bikes may never be perfect, and they will need a little more maintenance than bikes made in this century. Too much garage time is not healthy, you have to get out and ride.:bike:
 
Yup, I agree. While you don't want to get stranded again, using the voltage readings of a battery as a detailled indicator of the stat of chagre depends on all sorts of things like did you use your turn signal in the last 10 minutes, what is the temparature.

I'd say pick a route that is long enough to really test it but not be too much of a pain if you get stuck - and ride it.

Pete
 
Some of the most interesting times happen when things go sideways if not south. This is the voice of experience having been run off property (really now how fast can you run peddle cycling), fed, housed, heard interesting stories, shared a drink or a dozen, left a bike stashed in an old school Mennonite family barn for a week and hitchhiked 300 miles home all because of breakdowns. Shit happens, you'll live. Ride it.
 
Don't get me wrong, I'm all about those adventures and would welcome them as they come. But this is my daily ride. She takes me to work and home. She burned up two rectifiers within 10 miles from home. On the third, a 30 minute garage test in the early afternoon. That very evening, a 27 mile road test first in the neighborhood then up and down the local pike at 60mph.

Y'all are preaching to the choir. I had Stella out to meet Pete for lunch 5 hours after crimping the last terminal. Only sleep and a bike wash filled those hours. Believe me, I want to ride.
 
Yup - you're right Daniel. Don't take tooooo many chances, but do get out there.

Pete
 
37.2 miles on the third Chinese rectifier. No charge. All neg side diodes show 0.0 ohm continuity in both directions. Same fault symptoms as the last one.

I'm putting in an order for a couple of the rectifiers 5twins or Paul linked to. Not sure which yet.
 
DB, are you considering trying the stock rectifier again ? Just hoping you can enjoy a few more miles this weekend.. I'm hoping for some Sunday mornin riding up here as well ! -RT
 
DanielBlack said:
37.2 miles on the third Chinese rectifier. No charge. All neg side diodes show 0.0 ohm continuity in both directions. Same fault symptoms as the last one.

I'm putting in an order for a couple of the rectifiers 5twins or Paul linked to. Not sure which yet.
Click to expand...

Oh man that's terrible Daniel. I'm sorry you've been having so much trouble with your rectifier. I can't imagine what's happened.
 
Mailman, maybe a Sunday ride ? Its XS season starting Sunday up here in the rain forest. Im in ! Maybe lucky enough to get my indoor XS ornament outside to stay. Then maybe you two can watch me scratchin my head for a turn, But maybe not ! Im feelin lucky ! Passin it on too.. -RT
 
We need those dowsers from the “Water Witch” thread to step up there game and start dowsing for electrical gremlins.

Seriously Daniel, I’m not sure you have a batch of bad rectifiers. More likely you are blowing them from a problem elsewhere. On post 286 you mentioned that you had a run on blowing 1157 bulbs in the taillight. Could have been vibration. But perhaps the bulbs were in effect acting like fuses for an amp spike in the system.

Your stator tests good. But double check your stator for burnt or cracked housing. I have heard of (but never seen) a stator that test good cold. But has a break in the windings. When it heats up from current the wires expand and break the continuity. This would be similar to your bike charging at initial start, but loosing charge as the stator heats up.

Gurus, if there is a break in the windings when heated, then as the windings cool (from no current) they establish continuity again and the amps spike because the bike is turning 3-5K rpms?

Daniel, you are methodical, so you will get this problem solved! Best wishes.

ee
 
Thank you EE. Good thoughts. The taillight issue did resolve itself after I stuffed some bubble wrap behind the reflector. Three blown lamps within a couple hundred miles, none blown in the last thousand.

The stator is a possibility. I did check it last night when I pulled in to the garage. It was pumping out ~14VAC between whites at 1500rpm.
 
Agreed. I am not an electrical expert but I have spent my entire career using electrical and electronic equipment and the number of actual electrical component failures (aside from burnt out bulbs of course) that I have experienced could be measured on the fingers of one hand (well, maybe two - but it's been nearly 40 years). It simply doesn't happen that often.

Most electrical issues with a given component are either connector problems (loose, corroded etc.), or they're caused by a failure of ANOTHER component, or they are what are sometimes known as dumb thumb issues. (In Schlumberger Wireline, these were called Group 7 Non-Hardware or Software Failures). I can still hear my instructor at the training centre in Port Harcourt Nigeria yelling at me: "Pierre: do not make zee Group 7 f@ck-up or zee client - he will 'nut be 'appy!!! " (imagine that bellowed with a thick French accent in a very loud voice).

So....while I have no doubt that these rectifiers are dying - I think that the cause simply must be elsewhere as suggested by DoubleE and others. Accordingly, it seems a bit pointless to simply install another rectifier until the root cause has been identified, isolated and defeated.

My suspicion is that another charging system component is going south....or that it is related to the very cool and highly worthwhile LED lighting upgrades that Daniel has done - I very much doubt that it is simply vibration. These bikes all vibrate - and yet most of them operate quite reliably without continually destroying solid state components. Besides, I watched Daniel start Stella up and she is one of the sweetest running 650s I've ever seen.

Anyhow, that's my 1.57 cents (USD) - aside from saying to Daniel - you will get this fixed my friend, and when you do, it will likely turn out to be some simple dumb@ss thing but you will have learned a lot in the process.

Pete

PS - one way to test this would be to disconnect ALL lights and go for a ride - obviously with another rider alongside as a guard. No flames please - I recognise that this is an unorthodox and potentially risky course of action, but you need to isolate this to either the charging system- or - the lighting.
 
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Those numbers one the whites sound good. You may want to physically inspect the windings. Also, is your battery fairly new? If not, perhaps get it load tested. It may appear good in terms of voltage, but has gone bad in terms of load. In particular, the rectifier may be over worked trying to stuff amps (electrons) into a battery that won't take them. And because the voltage regulator isn't seeing more than 14.5+ volts on the battery, it continues to push the stator into action. If this were the case, I would expect to see your 15 or 20 amp main fuse blow before the rectifier (30amp), but get a load test and eliminate another variable.
ee
 
Thank you, Pete. This here bank accepts foreign advice at even exchange.

I'm happy to suspect my lighting rewiring and such as the culprit, but I'd appreciate an explanation of how it might affect a component on another circuit even though it seems to be working as designed.

Out of three fused circuits only one component on one circuit is acting up. All other features seem good.

I'm not saying "no", just "how might that be?"
 

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