Dynamo question

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MalcW
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Dynamo question

Post by MalcW »

Hi All. The E3L dynamo on my 650 has never really charged. It's fitted to a 12V positive earth bike that has a solid state voltage regulator unknown make and age. There had been an oil leak into the dynamo, so I fitted a new oil seal and cleaned the commutator and brushes, but it was still the same. I also tried flashing the dynamo, to no avail.

Recently I fitted an LED sidelight bulb in the headlamp so that at least if I wanted some form of light on the front the drain would be minimal. Again, riding along with sidelights on the ammeter showed a slight discharge. But yesterday, on an organised bike run I had the sidelight on because it was raining and rather dull (typical, after such a long dry spell down here) I suddenly noticed the the ammeter was registering a charge! So I tried the headlight. With sufficient revs, this too was showing a very slight charge, or at least balancing the load. Has anyone ever come across such a thing?

Perhaps if I don't have to invest in a replacement, I can spend some money on a new bike jacket, because yesterday clearly shows that mine isn't as waterproof as I thought it was!

Cheers,

Malc
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Re: Dynamo question

Post by 1608 »

I've not found a bike jkt that is waterproof yet!
Have you checked the out-put directly from the dynamo. ie. simply connect both terminals ( I believe D&E ) together and connect a 12v bulb btn them and earth. Better still use a volt meter.
oldandsmelly
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Re: Dynamo question

Post by oldandsmelly »

I was on the same ride as you on the near identical model 31. I have a boyer brandon powerbox fitted and it does the same thing as yours in that it appears not to be charging and then suddenly kicks into life.

I've figured out on my set up that the battery voltage has to drop down a bit before the unit starts charging. As it's a magneto bike, the only normal loss is from the brake light and with a healthy battery, the battery voltage drop over time is very low. Turning on my lights seems to hasten the charging kick in, but as they are LEDs, it's not straight away.

So, it could be that you don't have a problem after all or it could be a bad connection that the ride and moisture cleared up.

I have a Triumph jacket that is about 2 years old and was silly money but is completely waterproof. At least, I stayed dry on a very wet 250 miler down from Yorkshire recently.
Andy51
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Re: Dynamo question

Post by Andy51 »

Hi Malcolm, re your questions:
Is everything in your electrical system properly earthed? I have run separate earth wires to headlamp and tail lamp, indicators and engine (and thus dynamo as it is bolted to the crankcase), all terminating together on the same bolt as the battery earth wire. This turned my almost no charge dynamo into the nearest thing to a power house that a Lucas dyno will ever be.
I still have a Rukka one-piece oversuit I bought in the early eighties that is completely waterproof. On the downside, it is a pain to put on and take off. As soon as you introduce a possible path for water, i.e. seperate jacket and trousers, it will find its way in!

Cheers, Andy
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GOLDSTAR
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Re: Dynamo question

Post by GOLDSTAR »

I have a Merlin wax jacket and a pair of sailing salopettes made by Gill, it seems impossible to get motorcycle salopettes so these are the next best thing, the are one piece of course, come up under the arms thus preventing any water access to a waist type set of over trousers, the one drawback is 'tis a bloody pantomime to have a pee! :headbang: . kind regards
MalcW
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Re: Dynamo question

Post by MalcW »

Hi all, thanks for the replies.
1608, no I haven't checked directly, but I've looked up how to do so and I'll give it a try. It would be nice to know what the direct output is.
Oldandsmelly, your bike isn't that identical to mine - it looked much nicer! A nice sunny day after the ride meant at least I got my gear dried out. Your theory about the battery could be a point though; it could be a feature of the solid state box only cutting in after a certain point.
Andy51, as far as I can see I have the normal earthing, so I'll certainly try that. I guess you ran the earths from the headlamp and tail lamp mounting bolts? I don't have indicators - yet - but as soon as I do I'll do the same.
Goldstar, apart from the obvious problem with salopettes, as you point out, that's a very good idea; they never even occurred to me. I live on the coast, so I should be able to get some easily.

Malc
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clive
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Re: Dynamo question

Post by clive »

1608 wrote:I've not found a bike jkt that is waterproof yet!
Have you checked the out-put directly from the dynamo. ie. simply connect both terminals ( I believe D&E ) together and connect a 12v bulb btn them and earth. Better still use a volt meter.
The two terminals should be D and F shouldn't they.
clive
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cbranni
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Re: Dynamo question

Post by cbranni »

I have a Frank Thomas two piece suit, it has Gortex lining, I find really good but not so good when you tuck the legs into your boots, boots will fill up with water when it rains :roll:
only dead fish go with the flow
MalcW
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Re: Dynamo question

Post by MalcW »

clive wrote: The two terminals should be D and F shouldn't they.
That's correct; Dynamo and Field. I found that out when I looked up exactly how to test a dynamo.

Cheers,

Malcolm
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Re: Dynamo question

Post by 1608 »

Don't tuck your trousers in then :)
I did say I believe twas D&E, anyway The two terminals. :roll:
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