C15 Overcharging - I think?

[limeyrob]

Yes, regarding regulators.  Dynamos and alternators with brushes and coils in the rotor (like car alternators) can be regulated by varying the current in the armature or rotor so they only produce what is needed.  Our alternators are fixed with permanent magnet rotors so its impossible to vary the output other than be changing how the coils are connected.  So we have to burn off unwanted electricity which is what the Zener diode does. So there's a lot of heat.  It actually makes sense to run with the lights on since that is also burning power off.

[rhyatt]

I used a small square of aluminium sheet about 4" x 4" and bent a 1" angle on 1 edge.
There's enough bolt holes on the transverse channel the runs between the 2 seat frame tubes and mounted it there with the RR in line with the direction of travel.
Easy run for it's wires there and cool enough

[Derek996]

There is a modern trend towards series regulator which work by restricting the current from the alternator and have the advantage that they don't get hot. Shindengen make a range of MOSFET regulators, such as the FH020AA, featuring this and are used on most current bikes from Honda, Yamaha, Ducati, etc.
The attached picture from their website demonstrates the difference. Incidentally, you can use a 3 phase regulator on a single phase system, just leave nothing attached to the 3rd input terminal.

[Stevieo]

Thanks for the continued support everyone, Ive decided to keep the stator and get new reg/rec coil battery and bulbs all 12v - ill be looking for a standard reg with 2 yellow, a red and a black wire  - this seems to be the most common.

I still dont fully understand where the overcharge is coming from but im hoping its the fact that i have a 12v stator being used with a 6v reg? We will see

[limeyrob]

Well, I for one have learned quite a bit in the course of this discussion so it cuts both ways!
I think all of us who are familiar , experienced, scarred by old British bikes will have learned the lesson: It may look obvious and only have a few moving parts but that does not mean its simple to diagnose a fualt.  Quite the opposite.  Despite the logic of complexity it only takes a few parts to cause an impenetrable problem.  Amal carb, I rest my case.

[rhyatt]

That's the beauty of forums.
Like minded people sharing their knowledge and thoughts.

[Stevieo]

OK, a small update, i have removed all bulbs, coil, battery & regulator - no id or the regulator btw.

I have all 12v parts on order so will arrive by the end of the week.

One thing I have read is that now that I'm switching to 12v, the stator can be wired directly to the regulators 2 yellow wires, whereas before, on 6v they were wired into the loom. so this will bypass the emergency circuit and anything else not required for 12v operation. Also, the DC wires on the regulator can also bypass any loom connecters and go straight to the battery terminals. At least I hope this is the case, if anyone has any further knowledge on this then Id love to hear it. Thanks

Steve

*edit* it actually appears that derek996 has already mentioned the direct wiring on the previous page, must have missed it.

[rhyatt]

pretty much, although if you by pass the loom , you will bypass the ammeter , so you'll need to integrate the reg/rec output via the ammeter wiring (only the red output wire of course, the black goes to earth NEG).

[Tigerfeet]

When converting my C15 from 6v to 12v I took my brand new loom apart and altered it substantially to remove all the redundant wires (and to run separate earth's to all components - which is a personal preference). 

I am not at all sure whether you can run a 12v system using the standard 6v loom. I guess that redundant wires for the emergency position (and the extra lighting coils) will have no power input, and therefore won't cause any issues - but you would need to check that through very carefully - for every switch position.

[limeyrob]

Yes with a regulated 12V set up a lot of the complexity of the old style 6V is not needed.  They were regulating by switching more coils in for lights and you had "emerg" which implies they were expecting flat batteries.  You can wire the regulated 12V like any other modern vehicle with the regulator output going to charge the battery on a single wire.

[Derek996]

If the alternator wires are connected directly to the regulator and the regulator output wires are connected directly to the battery and ground then all the wires which previously regulated the charge are effectively disconnected and are redundant.

[Tigerfeet]

You are right. That does make the 'conversion' very simple.  (As my bike was in 1000 pieces and I was wiring it from scratch, making the loom 'bespoke' was an easy choice. So I never really looked at how you would convert an intact, running bike.)

[Stevieo]

Thanks again and thanks for posting the 12v wiring diagram too. I was going to disconnect and cap any wires not required on the ignition switch and light switch but it seems is not required as they just won't get used when bypassed

[Tigerfeet]

One thing I would urge you to consider is adding a fuse into the wiring. You will find a long debate about where a fuse should go - mine is on the brown/blue wire a couple of inches from the battery.... 

[Stevieo]

Just looked and thats exactly where there is a fuse by the previous owner, brown/blue going to battery neg.
thanks