Magneto/wiring help please

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Larry710
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Suzuki 2-Strokes: 1977 GT500

Re: Magneto/wiring help please

Post by Larry710 »

Try this again..
Image

Larry710 wrote:

Image

I thought it would be pretty straight forward :x

This is all the wiring diagram I have for the ebay purchased rectifier/regulator. How would you connect to it? What should I expect?
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jabcb
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Suzuki 2-Strokes: 69 T350 thru 75 GT750
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Re: Magneto/wiring help please

Post by jabcb »

Post a pic of the rectifier/regulator.
BAS (Bike Acquisition Syndrome) - too many bikes but have room for more

Suzuki:
GT750 2x75
GT550 72 & 75
GT380 72
T500 69 project & 73 project
T350 69 & 71
Honda 85 CB650SC & 86 CB700SC
09 Triumph Bonneville SE
Larry710
On the street
Posts: 34
Joined: Mon Sep 11, 2017 9:51 am
Country: Canada
Suzuki 2-Strokes: 1977 GT500

Re: Magneto/wiring help please

Post by Larry710 »

Link to the RR i got...
https://www.ebay.com/itm/202138206907" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;

Here is a pic of the bike on it's first ride since I bought it stripped down to the crank. Still a working progress.
As you'll notice I have a lot of extra parts!

Image
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jabcb
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Re: Magneto/wiring help please

Post by jabcb »

That looks to be similar to the Tympanium rectifier/regulator that I use.

The GT500 has 3 alternator output wires. Wire them up as shown here: viewtopic.php?f=2&t=4858&start=17

Y/G wires goes to one of the R/R yellow wires. It doesn’t matter which one.
R/G & G/W wires goes to the other R/R yellow wire.
The black wire is the ground.
The red wire is the battery + wire.
BAS (Bike Acquisition Syndrome) - too many bikes but have room for more

Suzuki:
GT750 2x75
GT550 72 & 75
GT380 72
T500 69 project & 73 project
T350 69 & 71
Honda 85 CB650SC & 86 CB700SC
09 Triumph Bonneville SE
Larry710
On the street
Posts: 34
Joined: Mon Sep 11, 2017 9:51 am
Country: Canada
Suzuki 2-Strokes: 1977 GT500

Re: Magneto/wiring help please

Post by Larry710 »

I got them wired as the link shows.

But I am still having issues. :x

if I run the headlight it kills the battery. like it did tonight!

i checked the R/R out put to battery, and I got -3.5v (negitive) red to red, black to black

So I switched red to black, black to red, and got +6.0v

Is there a detailed wiring schematic for the lighting coils. I am wondering if I mixed the wires when installing the 2 new coils last winter. And/or got the A coil mixed up with the B?

This is driving me to drink!!!
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jabcb
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Re: Magneto/wiring help please

Post by jabcb »

It doesn’t matter if you switch coils A & B.

Each coil has 2 wires for a total of 4 wires. Those 4 wires connect up to 3 wires (Y/G, R/G & G/W). Its possible to get this wrong & end up with the two coils working against each other. I’ll check to see how mine is wired up in the next few days.
Image
BAS (Bike Acquisition Syndrome) - too many bikes but have room for more

Suzuki:
GT750 2x75
GT550 72 & 75
GT380 72
T500 69 project & 73 project
T350 69 & 71
Honda 85 CB650SC & 86 CB700SC
09 Triumph Bonneville SE
Larry710
On the street
Posts: 34
Joined: Mon Sep 11, 2017 9:51 am
Country: Canada
Suzuki 2-Strokes: 1977 GT500

Re: Magneto/wiring help please

Post by Larry710 »

Soo...

how mine is wired....each charge coil has a black wire and white wire. both whites are soldered to the y/g. one black to r/g and one to g/w
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jabcb
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Suzuki 2-Strokes: 69 T350 thru 75 GT750
Location: southwestern Pennsylvania

Re: Magneto/wiring help please

Post by jabcb »

Sorry for the delay.

My charge coils have brown & black wires. The two brown wires connect to Y/G.
Yours is wired up the same. But its possible to install them upside down. Post a link to a pic of your setup
BAS (Bike Acquisition Syndrome) - too many bikes but have room for more

Suzuki:
GT750 2x75
GT550 72 & 75
GT380 72
T500 69 project & 73 project
T350 69 & 71
Honda 85 CB650SC & 86 CB700SC
09 Triumph Bonneville SE
Larry710
On the street
Posts: 34
Joined: Mon Sep 11, 2017 9:51 am
Country: Canada
Suzuki 2-Strokes: 1977 GT500

Re: Magneto/wiring help please

Post by Larry710 »

jabcb wrote:Sorry for the delay.

My charge coils have brown & black wires. The two brown wires connect to Y/G.
Yours is wired up the same. But its possible to install them upside down. Post a link to a pic of your setup

Yup, even before reading your reply I tried switching one around....

Image
I switched the one on the right, so the wires come out on the clockwise position, (like the left). I fired it up, and wolla! Consistant 13.5v going to the battery!

So I went for a ride with the head light on, to give it a workout, which resulted in nearly burning my bike to the ground. Come to find out, the battery that came in my lighting kit --> https://www.rockymountainatvmc.com/p/11 ... ghting-Kit" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;

Is a lithium battery. I assumed it had a over load protection built in, but nope. I had flames shooting 2' out the side, under the seat. I managed to get the fire out, but the battery is destroyed, and it melted the tail/brake/siginal light harness.
Image
So now i need to find a battery, small enough to fit under the seat, and not catch fire. I am looking at this one; https://shop.antigravitybatteries.com/p ... se/ag-401/" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;

but this part of the description has me worried:
"Custom builds like cafe racers or small bore customs up to 350cc. (Please note if you use older classic bikes from mid 1980s and earlier you should update the charging systems to a modern voltage regulator; damaged voltage regulator can overcharge the battery and damage it.)
Not for use with PWC."


However I have a updated regulator!

Thoughts?
Larry710
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Joined: Mon Sep 11, 2017 9:51 am
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Suzuki 2-Strokes: 1977 GT500

Re: Magneto/wiring help please

Post by Larry710 »

OH and ignore the black electrical tape on the Y/G.. It is soldered with heat shrink. I add the tape on top of the heat shrink in an attempt to provide more insulation in case that was the source of my problems.

Everything else after in the wiring is temporary until all these gremlins (charging system, battries catching fire, etc) are taken care of.
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jabcb
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Re: Magneto/wiring help please

Post by jabcb »

I don’t remember seeing a rectifier/regulator that looks the one you have so I did a bit of digging.
It looks like rectifier/regulators that were used on some PWC (personal water craft) from about 1990 to 2000. You’ll find them if you Google, “sea doo rectifier regulator”.

Lithium batteries are rather picky about charging voltage. Its likely that your fire was due to the incompatibility of the rectifier/regulator and the needs of a lithium battery.
Your link for the Antigravity battery lists best uses. It specifically states: not for use in PWC. That statement might be due to their knowledge of PWC rectifier/regulators.

I would not be surprised if you have another fire if you only do wiring repairs & install the Antigravity battery.

How much room do you have for a battery? There might be an AGM battery that fits?
Also if it were me, I would discard that rectifier/regulator & try to use a better one.
BAS (Bike Acquisition Syndrome) - too many bikes but have room for more

Suzuki:
GT750 2x75
GT550 72 & 75
GT380 72
T500 69 project & 73 project
T350 69 & 71
Honda 85 CB650SC & 86 CB700SC
09 Triumph Bonneville SE
Larry710
On the street
Posts: 34
Joined: Mon Sep 11, 2017 9:51 am
Country: Canada
Suzuki 2-Strokes: 1977 GT500

Re: Magneto/wiring help please

Post by Larry710 »

I am going to chat with a custom bike builder here in town next week, and see what he recommends. I agree with you on the R/R. I would like to go with something tried and tested. I'll see what he might use and if I can buy one from him.

I am questioning why I even need a battery. I have inquired about using a battery eliminator --> http://www.oregonmotorcycleparts.com/BEC.html" onclick="window.open(this.href);return false;
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jabcb
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Joined: Mon Dec 13, 2010 4:32 pm
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Suzuki 2-Strokes: 69 T350 thru 75 GT750
Location: southwestern Pennsylvania

Re: Magneto/wiring help please

Post by jabcb »

Rick’s Motorsports has a few rectifier/regulators specifically designed for lithium batteries: https://ricksmotorsportelectrics.com/bl ... regulator/
The site doesn’t list compatibility with any Suzukis, so some sleuthing would be required to figure out which one will work on a GT500.
BAS (Bike Acquisition Syndrome) - too many bikes but have room for more

Suzuki:
GT750 2x75
GT550 72 & 75
GT380 72
T500 69 project & 73 project
T350 69 & 71
Honda 85 CB650SC & 86 CB700SC
09 Triumph Bonneville SE
User avatar
jabcb
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Posts: 4240
Joined: Mon Dec 13, 2010 4:32 pm
Country: USA
Suzuki 2-Strokes: 69 T350 thru 75 GT750
Location: southwestern Pennsylvania

Re: Magneto/wiring help please

Post by jabcb »

Anitgravity’s FAQ has some useful info about their batteries. https://shop.antigravitybatteries.com/h ... qb3f7-8094

Sparck Moto has a single phase rectifier/regulator that they claim is OK with lithium batteries.
https://www.dimecitycycles.com/12v-sing ... er-reviews
http://www.sparckmoto.com/Products/Detail/7

Sparck Moto sells stuff mostly for vintage Hondas. I checked the hontdatwins.net forum. Some forum members are using that R/R with a lithium battery with good results.
BAS (Bike Acquisition Syndrome) - too many bikes but have room for more

Suzuki:
GT750 2x75
GT550 72 & 75
GT380 72
T500 69 project & 73 project
T350 69 & 71
Honda 85 CB650SC & 86 CB700SC
09 Triumph Bonneville SE
Larry710
On the street
Posts: 34
Joined: Mon Sep 11, 2017 9:51 am
Country: Canada
Suzuki 2-Strokes: 1977 GT500

Re: Magneto/wiring help please

Post by Larry710 »

So I went to a local battery supply/specialist and they recommended this...


Image


I feel much better with a lead acid!

Since I am running all LED's, headlight included, do you think having the g/w and r/g both supplying the RR is overkill? Thus supplying too much to the battery when there is minimal draw.

I feel like I should disconnect either the g/w, or r/g going to the RR. Would you agree?

I seriously appreciate all the btw, thanks so much.

Larry
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